OVERVIEW
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Life Classified can be needs Made of Distance from the Earth to the Sun Presence of an atmosphere Hydrosphere with liquid water Mild temperatures Cells Vital functions Tissues Organs Systems Asexual Autotrophs Water Carbohydrates Proteins Heterotrophs Minerals Lipids Nucleic acids Sexual Common Characteristics Animals Plants by en Taxonomy Monera Protoctista Fungi Plantae Animalia The five kingdoms Binomial nomenclature Eukaryotes Organic substances Inorganic substances Nutrition Reproduction Interaction Multicellular Unicellular Prokaryotes Levels of organisation The conditions of life on Earth Kingdoms Phylum Class Order Family Genus Species
1
OF THE UNIT
Living beings
Digital resources Inclusion and diversity Evaluation
WHAT ARE WE GOING TO?
Opening pages
Lynn Margulis. An exceptional biologist
1. Our planet and conditions for life on Earth
2. What is life on Earth made of?
3. Cells: the building blocks of life
4. Vital functions
5. The classification of living beings
6. The five kingdoms
Understand, reflect and test your skills
RESOURCES IN THE DIGITAL PROJECT
Document: ‘Biography of Lynn Margulis’
Video: Video ‘Before you begin’ Document: ‘My profession: microbiology’ Presentation: ‘What you need to know’
Video: ‘Life on Mars’
Inclusion and diversity: content ‘The Earth and its conditions for life’. Adaptation worksheets 1, 2, and 3, practice worksheets 4 and 5, and further study worksheet 6
Presentation: ‘Let’s remember what a chemical composition is.’
Inclusion and diversity: content ‘The composition of living beings’. Adaptation worksheets 1, and 2, practice worksheet 3, and further study worksheet 4
Videos: ‘The prokaryotic cell’, ‘Cellular theory’, ‘The eukaryotic animal cell’, ‘The eukaryotic plant cell’, ‘The use of the microscope’, ‘The size of cells’
Presentations: ‘The optical microscope’, ‘The shape of cells’
Inclusion and diversity: content ‘The characteristics and types of cells’. Adaptation worksheets 1, 2, and 3, practice worksheets 4, 5 and 6, and further study worksheet 7
Videos: ‘Bacterial division’ Presentation: ‘Cell respiration’
Inclusion and diversity: content ‘The characteristics and types of cells’. Adaptation worksheets 1, 2, 3, 4, 5, and 6, practice worksheets 6 and 7, and further study worksheet 8
Videos: ‘Linnaeus: the binomial nomenclature’
Presentations: ‘The dichotomous key of the five kingdoms’, ‘How to use a dichotomous key’ Inclusion and diversity: content ‘The characteristics and types of cells’. Adaptation worksheet 1, practice worksheets 2 and 3, and further study worksheet 4
Videos: ‘The levels of organisation’, ‘Are viruses living beings?’
Inclusion and diversity: content ‘The characteristics and types of cells’. Adaptation worksheets 1 and 2, practice worksheets 3, 4, and 5, and further study worksheet 6
Interactive activities: ‘Learn through play’ and ‘Test yourself!’
Document: Key concepts The essentials
Evaluation tests: basic, advanced and competence assessments
Written assessment and practice test generator
PEDAGOGICAL KEYS IN THE STUDENT’S BOOK
Academic and professional orientation
SDG. Goals: 2, 3, and 13 ICT
Descriptive text
Scientific thinking The What if?
ICT
Thinking hats
ICT Explanatory text Scientific thinking
ICT Scientific thinking. The Mirror
ICT Explanatory text Scientific thinking
ICT Descriptive text and explanatory text Scientific thinking
ICT Scientific thinking
Radial diagram and scientific thinking
ICT Evaluation
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Unit introduction
The unit begins by addressing the characteristics of planet Earth that make the development of life possible, introducing the different ‘terrestrial spheres’, which we will study in the last units. Firstly, we will study the basic characteristics of living beings, their chemical composition, their cellular structure and their capacity to carry out the vital functions. After this, we will study the classification of biodiversity in general, introducing students to the classification criteria.
Resources and materials
In addition to the Student’s Book and Teacher’s Guide, the resources in the following sections of the teachers’ web are designed to help with this unit: ‘Course plans, Teacher’s Guide and Project Documents’, ‘Diversity and Inclusion’ and ‘My Online Resources’.
Remember, the section ‘Diversity and Inclusion’ gives you access to an extensive collection of printable worksheets of various kinds (curriculum adaptation, practicals and further study) organised by content, allowing you to cater for all learners.
General suggestions
PRECONCEPTIONS AND LEARNING DIFFICULTIES
The study of the different types of cellular organisation can cause difficulty, in particular getting students to identify the two types of eukaryotic cells, not only with animals and plants, but also with other types of living beings, such as algae and protozoa. In the study of vital functions, it is interesting to focus on the differences between cellular respiration and gas exchange, or to associate the related functions both with highly-complex living beings, for example, animals, and with other simpler living beings, such as protozoa.
RELATED TASKS
Over the course of this unit, it might be helpful and motivating to do some practical tasks, in order to familiarise students with the scientific method and help them acquire certain competences and learning standards. We suggest doing the tasks corresponding to the experiment in the ‘Science workshop’ section of the Anaya Educación website.
We propose that you focus on perseverance and personal satisfaction for a job well done, the orderly presentation of work, precision, and collaboration with classmates.
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Academic and professional orientation
We recommend using the resource ‘My profession: microbiology’, in which students are given information about this profession and which will help them to understand the work of Margulis. There are different resources available to work on this key in the ‘Key resources’ section of anayaeducacion.es
ICT
Document: ‘Biography of Lynn Margulis’
Video: ‘Before we begin’
Document: ‘My profession: microbiology’
Presentation: ‘What you need to know’
Living beings
METHODOLOGICAL SUGGESTIONS
The activities on the opening page combine unit content with English acquisition focused activities. They could be led by either a teacher or by a Language Assistant, if you have one in your classroom. We suggest that you read or listen to the audio of the biography of the biologist, Lynn Margulis, who proposed classifying living beings into five kingdoms together with Karlene Schwartz. While listening to the text, you could focus the students’ attention on the stress, rhythm and intonation of words and sentences. This supports correct pronunciation and the association of the written word with spoken English.
WORK TOGETHER
Below are some questions which can help with reading the biography. In them, we connect the academic and professional orientation part of this unit with the research of Lynn Margulis.
This series of activities will also allow you to get an understanding of the level of knowledge that the students have before starting the unit.
1 A famous quote from Margulis was ‘Life is a symbiotic and cooperative union that allows those who network to succeed.’ What did she mean by this?
Therefore, with this phrase, Margulis wanted to highlight the important role that symbiosis played in evolution. In a symbiotic relationship, both organisms benefit to the point that this has often been the key to their evolutionary success, as is the case for the endosymbiotic process that gave rise to the eukaryotic cell.
2 Margulis was a great microbiologist. Do you know what this speciality is about? Do group research into how you can become a professional microbiologist and present it to the class.
CHALLENGES THAT LEAVE AN IMPRINT
LEARNING SEQUENCE
MY FRIDGE. A WHOLE NEW WORLD TO EXPLORE
1.1 Students need to study the environmental conditions found inside a fridge. They have to compare these environmental conditions with an ecosystem of their choice.
1.2 and 1.3 Students will look for nutritional information and components of a type of food of their choice.
1.4 Mould can be easily obtained by moistening a piece of sliced bread and storing it for a while in a warm area. Once the student has the mould, they can spread it to other pieces of sliced bread and compare the growth between a piece left in the fridge and another left in a warmer area.
1.5 Onion epithelium dyeing can be performed with methylene blue or neutral red. Dyeing animal tissue can be done with haematoxylin and eosin. Staining animal tissue without adequate prior preparation (paraffin embedding, microtome section, etc.) can be complicated therefore, we recommend having photographs prepared for your observation.
CLASSIFYING THE LIVING BEINGS IN MY FRIDGE
2.1 It is common for students to think that there are no representatives of the Monera kingdom, despite the fact that they will be present in almost all the foods in the fridge. As for protoctista, they are more common these days due to the use of algae in the kitchen, but a large amount of students can continue to associate them with plants instead of with protoctista.
2.2 We encourage teachers to take advantage of this opportunity to compare the culinary customs of the families of their students and to value what they can learn from their classmates.
2.3 The students will choose some of their favourite foods and look for the living beings they come from.
CHALLENGES THAT LEAVE AN IMPRINT for guidelines, go to anayaeducacion.es think of? Lots of people only associate them with that. They’re life itself! Let’s take bacteria as an example. They have existed they have colonised all possible environments. bet of bacteria in my purse, next to the photos of my children! in the USA. When was only 16 started university. was fascinated by living beings and wanted to study Biology. When graduated, decided to become scientists do. As scientific researcher, dedicated great part of my life to the study of microbes. was even the author of revolutionary theory: the theory of endosymbiosis. proposed modification to the classification of living and unicellular and multicellular algae became known My friends have described me as short, restless woman who is curious about everything, and think that’s very good summary! An exceptional biologist MY FRIDGE. A WHOLE NEW WORLD TO research area, such as temperature, relative humidity, light, etc. In this case the inside planet Earth. analyse the nutritional information listed. your favourite item of fresh food. 1.4 The secret life of your fridge. Grow mould them and put it inside your fridge. Leave few days. Have look at the contents of lot more living beings than with your naked animal tissue (formed by epithelial cells) look at them under the microscope. CLASSIFIYING THE LIVING BEINGS IN MY 2.1 Classify the fresh food in your fridge into the groups of living beings that you can’t find. Think about why they aren’t in your fridge. the class. Which species are most common and which are less common? fresh foods. Play guessing game in small groups. Take in turns to think of a living being but don’t tell anyone what it is! Step 2: Ask the person whose turn living being they’re thinking of. Step 3: Can you guess what is? Now it’s your turn to think of a living being. Lynn Margulis once said ‘Life did not networking.’ What do you think she You have been asked to write short article about the work of microbiologists for your school newspaper. Do research What is a typical day like for microbiologist? SPEAKING LANGUAGE BANK LIVING BEINGS 1 LYNN MARGULIS Find words in the text that mean… a) c) Take control d) A small bag for money Lynn says that her friends describe her as short, describe you?
Language plan
To complete activity 2, don’t forget to consult the Language plan section in the resource bank, where you will find the necessary information on how to write a descriptive text.
Thought development
There is also ‘The What if?’ resource to help the student to learn the basics to apply this key to activity 4.
ICT
Video: ‘Life on Mars’
Inclusion and diversity: content ‘The Earth and its conditions for life’. Adaptation worksheets 1, 2, and 3, practice worksheets 4 and 5, and further study worksheet 6.
Microbiology is the branch of biology that deals with the study of microorganisms, that is, those organisms that are microscopic. In general, microbiologists have studied biology, biochemistry or biotechnology before specialising in this area of knowledge.
3 Give the names of the five kingdoms that Lynn Margulis mentions. Give some characteristics of each.
Kingdom Monera includes prokaryotic living beings, bacteria; they are unicellular organisms, they do not have tissues, they are autotrophs and heterotrophs. Kingdom Protoctista, made up of unicellular and multicellular eukaryotic organisms without tissues; they are autotrophs and heterotrophs. Kingdom Fungi, which includes eukaryotic, unicellular and multicellular organisms without tissues, heterotrophs. Kingdom Plantae, formed by multicellular eukaryotic organisms with tissues, autotrophs. Kingdom Animalia, formed by multicellular eukaryotic organisms with tissues, heterotrophs.
Our planet and conditions for life on Earth
METHODOLOGICAL SUGGESTIONS
The greatest challenge on this double spread is helping students to better understand the characteristics of our planet, what makes life on Earth possible, and especially, the presence of atmosphere and its relationship with maintaining temperature.
In anticipation of these challenges, we have included a diagram which, besides showing the Earth’s layers, gives us an idea of how they interact with each other. It was not considered necessary to include the term: natural greenhouse effect, but the students are meant to understand this effect (mild temperature) intuitively, as well as its cause (presence of atmosphere).
We will continue to study the greenhouse effect in upcoming units in which students will study the atmosphere in greater depth.
SOLUTIONS
A good place to live
In this activity, we suggest that students use the ‘What would happen if…?’ thinker’s key, so that they can put into practice what they have learnt about the importance of the conditions for life on Earth.
This thinker’s key prompts very interesting responses, as it is designed to make students think about the consequences that might arise from two hypothetical situations. It is highly likely that it will encourage innovative ideas that will let students consider the importance of where our planet is situated, and how the conditions which allow the presence of life on Earth are the result of this. Although students should be aware of the third conditional and understand its usage in this context, they might struggle to formulate responses using it correctly. Therefore, allow responses which are formulated in the present tense as well.
Below are the answers to these two situations. There are also model diagrams which provide an example of how to apply this thinker’s key.
a) If Earth were to move further away from the Sun, the temperature on Earth would decrease because it would receive less solar radiation. This decrease in temperature would lead to more ice forming in the poles, which would lower the sea level. As a result of the Earth moving away
A B
Living beings could die
More ice in the poles
The sea level would lower
The temperature would decrease
What would happen if the Earth were to move further away from the Sun?
The Earth would move away from the Sun’s orbit
It would cause changes in Earth’s gravity
The orbit changes and, therefore, the seasons also change
Changes in temperature
The sea level would rise
Living beings could die
There would be less water available for living beings
The water would evaporate from the atmosphere and the hydrosphere
The poles would melt It would cause widespread drought
The temperature would increase
Living beings could die
What would happen if the composition of the atmosphere were to change (increase in the greenhouse effect)?
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A good place to live possible for life to exist on Earth. However, the Earth was closer to the Sun, or further away, or the conditions of the Earth’s atmosphere right shows what would happen the Earth was closer to the Sun. following cases (go to the resource bank at anayaeducacion.es the Sun? b) Look for information about the gases that form part of the happen if the composition of the atmosphere changed? For c) What is the habitable zone of a star? Investigate and name invent star with planet in its habitable zone and describe the 1 OUR PLANET AND CONDITIONS FOR LIFE ON EARTH 1.2 The conditions neccesary for life The Earth is the only planet in our Solar System that contains living found here, which is not the case for any other planet near to ours. The distance between the Earth and the Sun is ideal for life to exist. there would be too much solar radiation. we were further away, atmosphere protects the Earth from some solar radiation that is harmful to life and it also helps to keep our planet warm. also need for respiration and which plants need for photosynthesis. The average temperature on Earth 15 °C, which makes it possible beings and their environments. The Sun’s energy makes it possible liquid to water vapour). causes liquid water to evaporate, which falls back down to the Earth. This process occurs constantly and is known as the water cycle. there is a quick change between day and night. thousands of millions of stars that form our galaxy, known as the Milky 1.1 The Earth The Earth is solid planet mainly made up of rocks. It is surrounded only planet in our Solar System that contains life. The four things mentioned above, that is, rocks, gases, liquid water how they interact with each other. interact with each other: the biosphere, the atmosphere, the hydrosphere and the geosphere. The Earth’s different layers living beings inhabiting the Earth The biosphere made up of rocks The geosphere All of the liquid water surrounding the Earth Life could no longer exist Life could no longer exist. would increase. The poles There would be widespread drought. All the liquid water would evaporate from our atmosphere and hydrosphere. different orbit would change the seasons. The Earth would orbit Gravity on the Earth would change. Focus on English literally means the Greek bíos (life). Biology, biodiversity compound words which use this to understand better what they biography, biopic.
Cooperative learning
The resource ‘Thinking hats’ allows students to learn how to use the cooperative learning technique in the ‘Working with pictures’ activity.
ICT
Presentation: ‘Let’s remember what a chemical composition is’
Inclusion and diversity: content ‘The composition of living beings’. Adaptation worksheets 1, and 2, practice worksheet 3, and further study worksheet 4.
from the Sun it’s orbit would change, changing the seasons, and therefore, the temperature. The increasing distance between the Earth and the Sun would also change the force of gravity. These changes could affect living beings, which might die in the new conditions.
b) If the concentration of carbon dioxide on Earth were to increase (which would change the conditions of the atmosphere), the greenhouse effect would increase, thus causing an increase in the Earth’s temperature. This increase in temperature would cause the ice to melt in both poles, which would lead to the sea level rising in some areas. Other areas would experience drought and there would be less water for living beings, which could lead to them dying.
c) A star’s habitable zone is a region around it in which the planets there could have Earth-like conditions favourable to life. The main factors taken into account are the age and size of the star, which influence the type of radiation it emits, and its luminosity. There are other factors that must be taken into account to determine the habitability of a planet, such as the existence of magnetic fields, a greenhouse effect and the intensity of geological activity.
In the second part of the activity, the students must invent a planet and a star. It is important that they take into account the elements previously described and that they justify the differences with the characteristics of the Earth.
What is life on Earth made of?
METHODOLOGICAL SUGGESTIONS
The foundation of the unit is shown here. It is important to understand and remember basic concepts like cell, biomolecule and vital function. The greatest difficulty can be found in identifying that all living beings -including those that seem to have a bigger difference between each other such as animals, plants, fungi and microorganisms- are formed from the same kind of substances, are organised from cells and perform three vital functions. This latter characteristic is perhaps the least difficult, as students have previously studied it.
We suggest that teachers make sure students understand the difference between organic and inorganic material. This could be demonstrated by creating lists of real-life examples, such as oxygen, wood, rocks, cotton, water, wool, etc.
Teachers will notice that section 2.2 is called ‘Inorganic substances’, instead of inorganic biomolecules, as it is traditionally known in biology. This is because mineral salts are included in the summary and these salts are either in ionic form in a solution, or in crystal form and without molecules when in their solid state.
SOLUTIONS
Understand, think, search...
1 Living beings are made up of the same kind of substances (organic and inorganic) they are organised from similar units - cells; and they carry out three vital functions - nutrition, interaction and reproduction.
2 The most important organic components of all cells are inorganic components (water and mineral salts) and organic components (carbohydrates, lipids, proteins and nucleic acids).
3 Carbohydrates, lipids, proteins and nucleic acids are called biomolecules because they are unique among living beings and are not found in non-living matter.
4 a) 29 % of organic substances and 71% of inorganic substances.
b) Carbohydrates are the main energy molecules used by living beings in their metabolism. Lipids have the function of storing energy. Proteins, in certain situations, can also be used as sources of energy for the organism.
Look at the following molecules
a) The glucose molecule is made up of 6 glucose atoms, 6 oxygen atoms and 12 hydrogen atoms. The fatty acid molecule in the image is made up of 16 C atoms, 32 H atoms and 2 O atoms.
b) We suggest using the ‘Thinking hats’ cooperative learning skill to carry out this activity (in which students search for information on these macromolecules). This skill will help the students be more involved in learning as well as consolidating the key concepts through repetition: the key concept being the differences between proteins and nucleic acids.
Therefore, this an open answer question but you may want to use the following information to offer clues or guide students in their information search: Proteins are formed by the combination of amino acids. Its sequence makes different types of proteins. Nucleic acids are formed by nucleotides which, in turn, are formed by three units: a sugar molecule called deoxyribose, a phosphate group and one of four possible nitrogenous compounds called bases: Adenine (A), Guanine (G), Thymine (T) and Cytosine (C).
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2 WHAT IS LIFE ON EARTH MADE OF? As you already know, the biosphere consists of all the living All living beings have three things in common which enable us to distinguish them from non-living beings: organic inorganic substances. They are all made up They perform three vital functions: nutrition, interaction and 2.1 The chemical composition of life Everything in the universe is made up of tiny units called atoms. Oxygen and hydrogen are examples of different kinds of atoms. two hydrogen atoms join together with one oxygen atom and form a water molecule. non-living beings. Examples include liquid water found in living beings. Examples include carbohydrates, 2.2 Inorganic substances Liquid water an essential component for living beings. In fact, 70 % of living matter made up of liquid water. happen inside cells. Mineral salts help to regulate many vital processes. They also have structural function in the skeletons of living 2.3 Organic substances Carbohydrates are type of biomolecule that some cell structures, such as the cell wall, which you will study in this unit. Lipids store energy. They also provide insulation and form part of certain cell structures, in this unit. Living beings contain billions of protein molecules. For example, they help us to contract our muscles. Nucleic acids are relatively large molecules. In fact, organisms need to function, Understand, think, search... What are the main components of all living beings? Calculate the percentages of organic substances and inorganic substances in this b) Which biomolecules provide living beings with 70 % Look at the following molecules a) Look at the glucose and fatty acid molecules in while the white ones represent hydrogen and the hydrogen and oxygen molecules are there in each of these substances? are macromolecules. In other words, they are molecules with very complex structures. Do these molecules. What are they made up of? Protein Fatty acid molecule (lipid) Inorganic substances Oxygen Sodium chloride commonly known as salt, structure, which means it is organised like in the picture. However, when it is in an aqueous Chlorine Sodium
Thought development
There is the resource ‘The Mirror’ available to help the students learn the basics to use this thinking technique in activity 4.
ICT
Video: ‘The prokaryote cell’
Video: ‘Cell theory’
Video: ‘The animal eukaryote cell’
Video: ‘The plant eukaryote cell’
Inclusion and diversity: content ‘The characteristics and types of cell’ Adaptation worksheets 1, 2, and 3, practice worksheets 4, 5 and 6, and further study worksheet 7.
Cells: The building blocks of life (I)
METHODOLOGICAL SUGGESTIONS
The students’ prior knowledge of cells is limited, as they have only studied the basics previously. When asking students about cellular components, they often mention the nucleus and leave out the cytoplasm. This means that students are not considering the existence of cells without a nucleus (prokaryotes) and they are thinking of the existence of cells with a nucleus. Another difficulty for understanding cells lies in being able to visualise three-dimensional structures through the use of two-dimensional images, such as diagrams, photos or microscopic preparations. Students usually use the term ‘round’ as a synonym of ‘circular’ (flat) and ‘sphere’ (three-dimensional).
In anticipation of these difficulties, it is highly recommended that students make coloured drawings of the three types of cells in their notebook. They may also make models of cells using plasticine.
If you want to observe cells using a microscope, which will help to consolidate the concepts students are learning, there is a ‘Science workshop’ available in the resource bank on the Anaya website, which is dedicated to the microscopic observation of cells. We refer to this workshop at the end of the unit, as we think it would be very useful as a final review.
SOLUTIONS
Understand, think, search...
1 Cells are classified into prokaryotes and eukaryotes, according to whether their dispersed repetitive DNA is in the cytoplasm (prokaryotes) or inside a nucleus (eukaryotes), and according to whether they have a large variety of organelles, such as mitochondria, chloroplasts etc. (eukaryotes), or only ribosomes (prokaryotes).
2 a) The cytoplasm.
b) The cell membrane or plasma membrane.
c) Genetic material (DNA).
3 Answer in your own words.
As well as the interest, effort and ability to select information demonstrated by students when carrying out the activity, the planning and knowledge gained through conducting research online is also valuable. There is more information available online at the Anaya Educación website explaining how to develop digital citizenship.
4 In this activity, we suggest that students use the thinker’s key called ‘The mirror’. Using this key, students will compare animal and plant eukaryotic cells based on their similarities and differences and then reflect on this comparison.
Eukaryotic animal cells
Distinguishing characteristics
Centrioles
Cilia and flagella
Eukaryotic plant cells
Distinguishing characteristics Similarities
Plasma membrane Cell wall Cytoplasm
A nucleus that contains the DNA, the nucleoplasm and the nucleolus protected by the nuclear membrane
Common eukaryote organelles: ribosomes, endoplasmic reticulum, Golgi apparatus, cytoskeleton, vesicles, lysosomes
Chloroplast
Large vacuoles
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UNIT 3 CELLS: THE BUILDING BLOCKS OF LIFE 3.1 What are cells like? Biomolecules group together to form more complex structures inside In general, cells are microscopic in size, so we cannot see them with the naked eye. As result, we could not study them until microscopes were invented and further developed. All cells are made up of the following fundamental components: The plasma membrane, which thin layer that protects the cell. from the surrounding environment. The cytoplasm, which is kind of liquid that fills the inside of the Genetic material, which is made up of DNA fibres. This contains all the information needed to control cell functions and can be passed Organelles, which are small structures that specialise in performing specific functions. Not all organelles are found in all the different As result, the DNA found in whose task is to synthesise proteins. They may have Eukaryotic cells are more complex than prokaryotic They have plasma membrane and cytoplasm, which contain ribosomes. Mitochondria are an example of this type There are two different types of eukaryotic cells: unicellular organisms such as protozoa, which you will study later on. algae. They have a and organelles that can only be found in plants. For example, organelles are specialised in photosynthesis. Large vacuoles How do we classify cells as prokaryotic or eukaryotic? a) This contains mainly water and dissolved substances. c) This controls cellular activity. 3 cells taken under an electron microscope. a) Draw the shape of them in your notebook and label the structures b) Which structures have you identified? Which are present in all the function of each structure? Plasma Genetic Flagella Understand, think, search... plant cell and the eukaryotic animal cell, then copy (learn more about this tool at anayaeducacion.es Eukaryotic animal cell Nucleus Cytoplasm Eukaryotic plant cell Genetic Vacuole Cytoplasm Similarities Eukaryotic animal cell Eukaryotic plant cell
ICT
Video: ‘Using the microscope’
Presentation: ‘The optical microscope’
Presentation: ‘The shape of cells’
Video: ‘The size of cells’
Inclusion and diversity: content ‘The characteristics and types of cell’ Adaptation worksheets 1, 2, and 3, practice worksheets 4, 5 and 6, and further study worksheet 7.
Cells: the building blocks of life (II)
METHODOLOGICAL SUGGESTIONS
We continue the study of cells on this double spread. Students usually do not fully understand micro and macro in the context of cells, which may cause difficulties when studying the size of cells. We also suggest asking about students’ prior knowledge of scales, powers and conversion of units.
SOLUTIONS
Analyse these microscopy images
a) From left to right: 1.6 x 0.6 µm; 105 µm diameter; 80 x 30 µm.
b) From left to right:
• Bacteria, prokaryotic cell, as we can see it lacks a nucleus, and we can observe dispersed, repetitive DNA in the cytoplasm.
• Eukaryotic plant cell. We can identify this by the presence of the nucleus, in which we can see the nucleolus and the chromatin, as well as the presence of the plant cell’s own organelles, such as chloroplasts and large vacuoles.
• Ciliate protozoa, paramecium, and eukaryotic animal cell, as we can see the ciliates on the entire surface of the cell, the typical shoe shape, as well as several vacuoles, some of which look like stars, and lysosomes.
c) Students must draw a diagram of the cells in the image and show some recognisable parts. In the prokaryotic cell, the DNA, the membrane and the cytoplasm are easily recognisable. In the eukaryotic plant cell, the nucleus, the cell wall, the cell membrane, a vacuole, the cytoplasm, the chloroplasts and some mitochondria are recognisable. In the eukaryotic plant cell, the nucleus, the cell wall, the cell membrane, a vacuole, the cytoplasm, the chloroplasts and some mitochondria are recognisable.
Different cell shapes
a) Answer in your own words. Students should write descriptions that are not only correct and related to the content studied, but also correct as regards- grammar and spelling. Example phrases include:
Spermatozoon: A cell divided into a small oval-shaped body with a long flagellum.
Ovum: A large round cell.
Adipose cell: A round cell which has a cytoplasm mainly made up of fat.
Muscle cell: A long cell with several nuclei.
Hepatocyte: A cell with many different sides.
Cone: A long cell in which we can see a central body, an extension in the form of a cone at one end, and an extension with nerve endings at the opposite end.
Pigment cell: A cell with an oval-shaped nucleus and several extensions that give it an irregular shape.
Red blood cells: Small round cells in the shape of a button.
Neuron: A star-shaped cell in which we can see a central body with several extensions, and a long extension that is covered.
Epithelial cells: Cells with a prismatic shape which are arranged close to one another without leaving any spaces and that have several villi at one of their ends.
b) Answer in your own words. Besides what has been mentioned in the previous section, students shall be assessed on how they search and select information following the guidelines mentioned in unit 0. Example phrases include:
Ovum: It is the female gamete. Its function is to transmit the genetic material of the organism to its offspring. The DNA of the ovum joins the DNA of the spermatozoon, which completes the genetic transfer that is characteristic of the species. Furthermore, once the ovum is fertilised, it will turn into an embryo, which feeds off the nutritional substances that the ovum contains during its initial stages. This is why it is a large cell that contains a large amount of reserve substances.
Muscle cell: Muscle cells are responsible for muscle contraction and movement. This is why they are long and contain a large amount of fibres.
Red blood cells: These cells have the function of transporting oxygen through blood due to the fact that they contain a large quantity of haemoglobin, a protein which is able to bind with oxygen. Its round shape and small size allow it to flow through even the smallest blood vessels (capillaries).
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CELLS: THE BUILDING BLOCKS OF LIFE 3.3 Cell size vary greatly in size. Nevertheless, most cells are microscopic. microscope Cells are measured in units of length known as micrometres m). m 0.001 mm of cell. In general, they measure between 7 micrometres, cells in the liver measure 20 micrometres, sperm Plant cells between 10 and 100 micrometres in length. Some cells 3.4 Cell shape In addition to having different sizes, cells also have different shapes. flat or star-shaped. There are other shapes too. The shape of a cell is determined by its function. For example, red This allows them to carry as much oxygen as possible. Neuronsarestar-shapedwithbranchesthatallowthemtocommunicate Muscle cells are long, to allow them to contract. The cells covering our organs are usually cube or prism shaped. Focus on English through a microscope at a thin walled boxes. They reminded him of the small rooms, called cells, that monks lived in. Nowadays, cell more commonly used as a prison cell. Create A cells mosaic. Mosaics are type (called tesserae) of different materials. In the same way as tesserae in mosaic, cells join together to form tissues and Look at them and answer the following questions. a) Calculate the true size of the cell by using the scale above each What kind of cells are they? How do you know? c) Draw diagram of each cell in your notebook and label the Analyse these microscopy images a) Look at the cells in the picture above. Describe the shape of each one. their shape to the functions they carry out. c) The cells in the picture are not to scale. This means that they cells you picked for question b. Then, put them in order from Different cell shapes Red blood cells Spermatozoon (sperm cell)
Presentation: ‘Cell respiration’
Video: ‘Bacterial division’
Inclusion and diversity: content ‘The characteristics and types of cell’ Adaptation worksheets 1, 2, 3, 4, 5, and 6, practice worksheets 6 and 7, and further study worksheet 8.
Neuron: Cells in the nervous tissue that transmit the nerve impulse due to their extensions, dendrites and axon, which allow different neurons to connect to one another.
c) Red blood cells; small muscle cell; neuron (without taking into account the length of the axon); ovum; and large muscle cell.
Vital functions
METHODOLOGICAL SUGGESTIONS
We suggest taking advantage of the images included on these pages to help students better understand all of the processes carried out in the vital functions. The greatest difficulties come from misconceptions students have about nutrition and interaction. Students often think that nutrition refers only to eating and that interaction is only about interactions between individuals. To make it easier for students to understand, we recommend drawing a diagram, which lists the different processes and links them to real-life examples.
SOLUTIONS
Think about the types of nutrition
The labels correspond to the respiration process which takes place in all cells (in the mitochondria) and is carried out by all living beings.
Imagine you could choose a mode of reproduction depending on the conditions
The main advantage of asexual reproduction is that it can be very fast because it does not require the meeting of two organisms. The main disadvantage is that it limits the mixture of characteristics that occurs in sexual reproduction.
The second question may have an open answer and it is important to encourage students to offer reasoned explanations for their answers.
Parthenogenesis is a type of reproduction in which unfertilized female gametes are capable of creating a fully-formed organism.
An open-ended question in which reasoned responses and scientific justification should be encouraged based on how the process occurs in the species in which it occurs.
The classification of living beings
METHODOLOGICAL SUGGESTIONS
Students often have an intuitive capacity for classifying living beings, which you can take advantage of while teaching the concept of taxonomy. Scientific characteristics that students already know, such as cell types, internal organs and the vertebral column can be used to illustrate this concept. You might want to ask your students to research and write a short biography of Carl Linnaeus, which will help them get a better understanding both of the need for a system of classification and for the rules to follower in order to name living beings. Remember that there is also a reading related to this subject in the ‘Scientific readings’ section in the resource bank.
SOLUTIONS
‘Linnaeus: the binomial nomenclature’ Presentation: ‘The dichotomous key of the five kingdoms’, Presentation: ‘How to use a dichotomous key’ Inclusion and diversity: content ‘The characteristics and types of cell’ Adaptation worksheet 1, practice worksheets 2 and 3, and further study worksheets 4.
Understand, think, search...
1 Species: a group of living beings or taxon, which groups together individuals that are similar enough to be able to reproduce with one other and produce fertile offspring.
2 Beetles: Order Coleoptera.
Insect: Class Insecta.
Ant: Family Formicidae.
Giraffe: Genus Giraffa.
3 Holm oak: Quercus ilex.
Iberian lynx: Lynx pardinus.
Dog rose: Rosa canina.
Classifying an unusual species
Open answer. In this activity, creativity and artistic ability are employed in a scientific setting. To assess the activity, you will need to pay attention to the level of accuracy when detailing the characteristics and each taxon of the species invented by the student.
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ICT
4 VITAL FUNCTIONS Think about the roles of nutrition three vital functions. are fundamental processes that must be carried out in order to sustain life. 4.1 Nutrition Nutrition is the vital function through which living beings obtain the matter and energy Obtaining nutrients organic inorganic. Nutrients are substances that living beings take in. They are used types of nutrition: synthesise organic nutrients. Examples of inorganic energy. This process is known as photosynthesis. Heterotrophic nutrition means that from other living beings is order to produce organic nutrients and energy. Respiration (CO in process we call respiration. mitochondria. In the presence of oxygen (O complex molecules are converted into liquid water from the cell. This process also generates carry out their functions. Transporting substances Substances pass in and out of unicellular organisms organisms do not come into direct contact with mechanisms for absorbing, transporting and Cellular excretion substances, such as CO and liquid water. Other 4.2 Interaction living beings respond to internal or external changes Stimuli are the changes that occur in an organism’s by living beings. Living beings are able to detect certain stimuli, such as Preparing response: coordination Living beings process the information receptors and decide how to respond through series Coordination can take place within one carried out by complex systems made up of specialised tissues and organs. The response prepared during the coordination stage These effectors produce movement, substances changes in body’s shape or function, amongst other 4.3 Reproduction Reproduction is the vital function carried out by living beings to create new living beings guarantees species survival. There are two types of reproduction: asexual and sexual. Asexual reproduction (progenitor) producing copy of itself, by itself. This Sexual reproduction progenitor. Together, they produce a descendant that gametes are necessary for this process. Autotrophic nutrition Heterotrophic nutrition dioxide Organic nutrients compounds. Which process are these compounds pictures? energy Oxygen dioxide dioxide Inorganic nutrients Organic nutrients are obtained through food. sticking their tongues out and to light by turning their flowers living being, which has both progenitors. Female gamete Asexual reproduction Sexual reproduction Male (progenitor) Daughter cells (descendants), parent Imagine you could choose mode of reproduction depending Some organisms can choose to reproduce asexually or sexually, depending on the could be and answer the questions: What are the advantages of each process? reproduce in one way or the other? Find out what parthenogenesis is and write humans were parthenogenetic organisms, how do you think we would reproduce? Interaction Types of reproduction ICT
UNIT 5 THE CLASSIFICATION OF LIVING BEINGS to classify them into groups. This helps us to identify them more easily and to study them better. The criteria used to separate 5.1 Taxonomy is the science of classifying living beings. In the 18 century, the Swedish began to group living beings organised them into different kingdom. Each kingdom groups many species. Each species is group of living beings that are so similar they are capable of The diagram shows the different taxa. The plant kingdom includes anything from the oak tree to the common giraffes! Each time we move down taxon, the living beings included us to species. 5.2 Binomial nomenclature was given to all living beings. This name usually written in italics and consists of two words. The first word, beginning with a capital letter, is is always written in lower case, is the specific name and is used only scientific name for sparrow is Passer domesticus. Understand, think, search... What is species? use to refer to living beings do not They often refer to groups of following common names refer to: Find out the scientific name and the dog rose. Carl Linnaeus (1707-1778) the father taxonomy. Taxonomy hierarchical system used to classify living beings into different groups. An organism An example of plant and animal taxonomy Kingdom Phylum Class Order Family Genus Species Plants Angiosperms Dicotyledons Asterales Pseudanthiums Bellis Bellis perennis Animals Arthropods Insects Beetles Scarabaeidae Copris Copris hispanus Taxa are groups used to seven different taxa, namely: kingdom, phylum, class, order, classify. Imagine you have discovered an unusual species and you Invent a new species choosing any characteristics you like, then names of the taxa and the organisms that belong to it until you
Video:
Video: ‘The levels of organisation’ Video: ‘Are viruses living beings?’ Inclusion and diversity: content ‘The characteristics and types of cell’ Adaptation worksheets 1, and 2, practice worksheets 3, 4,and 5 and further study worksheet 6.
The five kingdoms
METHODOLOGICAL SUGGESTIONS
We recommend that your start studying this content by getting students to recall the types of cells and nutrition, which they have already studied in this unit. Then you could proceed to explain the five kingdoms and their characteristics. It could be a useful activity to get students to copy the diagram into their notebooks, as it has been designed to help them better understand the content.
It is also important to correct some common mistakes: for example, including algae in the Plant Kingdom or confusing mushroom-producing species with plants, etc.
SOLUTIONS
Analysing the five kingdoms
a) In the monera, protoctista and plant kingdoms. b) In the monera, protoctista and fungi kingdoms. c) In the plant and animal kingdoms. d) In the animal kingdom.
Language plan
In these pages, students are offered a series of activities on which they can analyse what they have learned. In addition, we suggest that you remind your students of the importance of collecting the work material for each unit in your portfolio.
Thought development
Do not forget to consult the document ‘Keys to the Project’ to inform the students how to make the visual organiser ‘Conceptual Map’ for carrying out activity 1.
Entrepreneurial culture
Do not forget to consult the document ‘Project Keys’, with which you will have information about the assets and the dimensions that are worked on in this key. ICT
Interactive activities: Learn while playing and Get testing!
Document. Science workshop ’See cells under the microscope’
Sheets: Concepts sheet 2
The essentials
Assessment tests: basic, advanced and competency
Generator of written evaluation and exercise tests
1
Challenges that leave an imprint
UNDERSTAND
Organising your ideas
Interaction Reproduction
Prokaryotic cell
Formed by cells
Perform the vital functions Eukaryotic cell
Living beings
Plant
Have the same composition
Nutrition Animal Inorganic substances (water and mineral salts)
Organic substances (carbohydrates, lipids, proteins and nucleic acids).
Summarising
2 The purpose of the following activity is for students to make a synthesis or summary of the most relevant points of the unit, which are the following:
• The characteristics which make life possible on Earth are: the distance of the Earth from the Sun; the existence of a protective atmosphere which contains vital gases such as oxygen and carbon dioxide; the existence of liquid water, and the existence of seasons that moderate the climate.
• All living beings are made up of the same type of substances: organic and inorganic substances. Living beings are organised from similar units: cells. Living beings carry out the three vital functions: nutrition, interaction and reproduction.
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ICT
UNIT Analysing the five kingdoms Use the picture to answer the autotrophs? b) Which kingdoms include c) Which kingdoms include organisms with tissues? organisms with tissues, organs and systems? 6 THE FIVE KINGDOMS Levels of organisation in plants Levels of organisation in animals 6.1 The organisation of living beings Living beings can be unicellular or multicellular. out all the vital functions. They can be prokaryotic or eukaryotic cells. are always eukaryotic. Most of the time, the cells in multicellular –same function. – Organs, which are groups of different tissues, designed to carry – Systems, which are made up of different organs and carry out more complex process. 6.2 The five kingdoms Organisms are organised into five main groups, based on factors such Cell type. Organisms can be prokaryotic or eukaryotic. Number of cells. Organisms can be unicellular or multicellular. Whether or not they have tissues autotrophs or heterotrophs. kingdoms: Kingdom Monera, Kingdom Protoctista, Kingdom Fungi, Kingdom Kingdom which form which form Organs Organs the living autotrophs or heterotrophs. They sometimes form colonies. They may be made up of one cell (for example, protozoa and are autotrophic organisms. Organisms in this group are made up of eukaryotic cells. They are form tissues. Examples include mould and mushrooms. Kingdom Fungi Organisms in this group consist of eukaryotic cells, with a rigid cell almost always have organs and systems. They are heterotrophic organisms. Kingdom Animalia
CHALLENGES THAT LEAVE AN IMPRINT Organising your ideas In your notebook, fill in the spaces in the concept map and extend its branches. Go to the Living beings Have the same composition Prokaryotic Summarising Use these points to write your own unit summary: What do all living beings have in common? What is the difference between autotrophic and asexual reproduction? What is the main difference between prokaryotic animal cells and eukaryotic plant cells? beings? What species? Can you think of two examples? The kingdoms with prokaryotic cells and the kingdoms with eukaryotic cells? b) The kingdoms with beings that have tissues c) The kingdoms with beings that only use autotrophic nutrition, the kingdoms with beings that only use heterotrophic nutrition, and the kingdoms with beings that use both Interpreting pictures 3 2 Look at the pictures below and answer the questions: C to? c) Which ones form tissues and which ones don’t? d) What type of nutrition and reproduction does Applying your knowledge a) Nucleic acids are the main source of cell energy. and their regulatory functions. activity. d)
10 000 000 million cells: a) How many millions of millions of cells are there b) How many millions of millions of cells are there in an elephant with a mass of 6 800 kg? observed in sample of pond water. a) If we put 1 320 similar protozoa in line, how b) How many protozoa would you need to make line measuring 250 metres? nutrients. b) Plants use solar energy to make their organic c) Plants don’t use energy from food because they from organic nutrients. Do the following words refer to type of cell, tissue, a) Lymphocyte b) c) Digestion d) e) Circulatory Moving forward 10 Read this text and answer the questions: Some animals, like starfish and lizards, can regenerate amputated parts of their bodies. an arm or leg, but our bodies are constantly regenerating cells not all the cells
our
regenerate; ability to make copies
themselves. Cells that can regenerate are called stem cells. any
cell
order to replace others that regenerating different parts
examples
b)
started
understand
The genetic material of cells composed mainly
in
bodies can
of
type of
in
of the body.
to support your answer.
Do you think is possible to regenerate any are used.
to
the relationship between living beings and the conditions the self-assessment worksheet and complete it. between living beings and the TEST YOUR SKILLS Go to anayaeducacion.es and complete the self-assessment worksheet to test 47 46
Language plan
In these pages, students are offered a series of activities on which they can analyse what they have learned. In addition, we suggest that you remind your students of the importance of collecting the work material for each unit in your portfolio.
Thought development
Do not forget to consult the document ‘Keys to the Project’ to inform the students how to make the visual organiser ‘Conceptual Map’ for carrying out activity 1.
Entrepreneurial culture
Do not forget to consult the document ‘Project Keys’, with which you will have information about the assets and the dimensions that are worked on in this key.
ICT
Interactive activities: Learn while playing and Get testing!
Document. Science workshop ’See cells under the microscope’
Sheets: Concepts sheet 2
The essentials
Assessment tests: basic, advanced and competency
Generator of written evaluation and exercise tests
• The difference between autotrophic and heterotrophic nutrition is that autotrophic nutrition consists of synthesising organic nutrients from inorganic nutrients, such as carbon dioxide. An example of autotrophic nutrition is when solar energy is used in photosynthesis. Heterotrophic nutrition consists of obtaining organic nutrients and energy from the organic matter of other living beings.
• The difference between sexual and asexual reproduction is that in asexual reproduction, offspring are produced that are identical to one parent individual, whereas, in sexual reproduction, two parent individuals of the opposite sex (which produce masculine and feminine gametes) produce offspring which are similar to them. Specialised reproductive cells called gametes are necessary for sexual reproduction.
• The main difference between eukaryotic and prokaryotic cells is the presence of a nucleus (a nuclear membrane that surrounds and protects the genetic material).
• The main difference between animal and plant cells is their type of nutrition and some organelles that are only found in one or the other.
• Plant cells are autotrophic due to their chloroplasts in which photosynthesis takes place. Animal cells are heterotrophic, as they do not have chloroplasts.
• Other organelles that are exclusive to plant cells are the cell wall and the large vacuoles. Unlike plant cells, animal cells have centrioles.
• The main taxa for classifying living beings are: kingdom, phylum, class, order, family, genus and species.
• A species is defined as a group of similar individuals which can reproduce, producing fertile offspring. Examples: sparrow Passer domesticus, poppy Papaver rhoeas.
• The five kingdoms of living beings and their characteristics are:
– Kingdom Monera, which includes unicellular, prokaryotic organisms. Their nutrition may be autotrophic or heterotrophic, and sometimes they form colonies.
– Kingdom Protoctista, which includes organisms with eukaryotic cells. There are unicellular organisms (protozoa, microscopic algae, etc.) and multicellular organisms that do not form tissues (large algae). Protozoa have heterotrophic nutrition, and algae have autotrophic nutrition.
– Kingdom Fungi, which includes organisms with eukaryotic cells. Their nutrition is heterotrophic. There are unicellular fungi such as yeast, or multicellular fungi that do not form tissue, such as mould and the fungi that form mushrooms.
– Kingdom Plantae, which includes organisms with eukaryotic cells that have rigid walls and chloroplasts. They are multicellular organisms with tissues and almost always have organs. Their nutrition is autotrophic.
– Kingdom Animalia, which includes multicellular organisms with eukaryotic cells that form tissues and, almost always, organs and systems. Their nutrition is heterotrophic.
• The only kingdom with prokaryotic cells is the Kingdom Monera, as the rest of the kingdoms are formed by organisms with eukaryotic cells.
• The kingdoms which have organisms with tissues are the plant and animal kingdoms, whereas the monera, protoctista and fungi kingdoms do not have organisms with tissues.
• The kingdom which only has autotrophic nutrition is the plant kingdom. The kingdoms which only have heterotrophic nutrition are the animal and the fungi kingdoms, and the ones which have both types of nutrition are the monera and the protoctista kingdoms.
Interpreting pictures
3 1.- nucleus; 2.- cytoplasm; 3.- plasma membrane; 4.- mitochondrion
4 a) C belongs to the animal kingdom, D belongs to the plant kingdom, B and E belong to the protoctista kingdom, A and F belong to the fungi kingdom and G belongs to the monera kingdom.
b) Single cells are A, G and E; multi cells are B, C, D and F.
c) The following form tissues: C and D. C and D have organs, and only C has structures or systems, although they are very basic.
d) Autotrophic nutrition: B, D and G. Heterotrophic nutrition: A, C, E, F and G.
As regards reproduction, some can have the two types: sexual and asexual.
Asexual reproduction: G, A, B, E.
Sexual reproduction: B, C, D, F.
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CHALLENGES THAT LEAVE AN IMPRINT UNIT UNDERSTAND Organising your ideas In your notebook, fill in the spaces in the anayaeducacion.es Living beings by cells Prokaryotic cell Summarising What makes life possible on our planet? heterotrophic nutrition? And between sexual and cells and eukaryotic cells? What is the main difference between eukaryotic animal cells and eukaryotic plant cells? What are the main taxa for classifying living What are the five kingdoms of living beings? What are their main characteristics? What are: a) The kingdoms with prokaryotic cells and the and the kingdoms with beings that don’t have c) The kingdoms with beings that only use beings that only use heterotrophic nutrition, types of nutrition? Interpreting pictures Name the labelled structures. What type of cell is this? 4 Look at the pictures below and answer the a) What kingdom does each living being belong b) Which living beings are unicellular and which are multicellular? Which ones have organs? Which have systems? each living being use? Applying your knowledge Are the following statements about cell components b) Proteins are important because of their structure c) Lipids are carbohydrates that regulate cell activity. of nucleic acids. If 5 kg of animal mass contains approximately in human being with mass of 55 kg? b) How many millions of millions of cells are there c) What the approximate mass of one animal cell? A protozoan measuring 110 micrometres was long would the line be? b) How many protozoa would you need to make a) Fungi use solar energy to make their organic nutrients. Plants don’t use energy from food because they use energy from sunlight. d) All living beings extract the energy they need organ or system? a) Lymphocyte d) Neuron Moving forward can regenerate amputated parts Human beings can’t regenerate an arm or leg, but our bodies like those in our blood, our skin and our liver. But differentiated cells, for example, have lost the ability to make copies of themselves. Stem cells can multiply and transform into are damaged or old. They act as reserves for regenerating different parts of the body. a) Can all the body’s cells regenerate? Give some c) Do some research and describe how stem cells REFLECT In this first unit you learned about the great biodiversity found in fridge and you necessary for life. To reflect on your learning, go to anayaeducacion.es the self-assessment worksheet and complete it. experiment. your competencies.
Language plan
In these pages, students are offered a series of activities on which they can analyse what they have learned. In addition, we suggest that you remind your students of the importance of collecting the work material for each unit in your portfolio.
Thought development
Do not forget to consult the document ‘Keys to the Project’ to inform the students how to make the visual organiser ‘Conceptual Map’ for carrying out activity 1.
Entrepreneurial culture
Do not forget to consult the document ‘Project Keys’, with which you will have information about the assets and the dimensions that are worked on in this key.
ICT
Interactive activities: Learn while playing and Get testing!
Document. Science workshop ’See cells under the microscope’
Sheets: Concepts sheet 2
The essentials
Assessment tests: basic, advanced and competency
Generator of written evaluation and exercise tests
Applying your knowledge
5 a) Nucleic acids are the main source of energy for cells. False. Carbohydrates are the main source of energy for cells.
b) Proteins are important due to their structural and regulatory functions. True.
c) Lipids are carbohydrates that regulate cell activity. False. Lipids are not carbohydrates.
d) The genetic material of cells is mainly made up of nucleic acids. True.
6 a) 110 billion; b) 13 600 billion; c) A cell will have a mass of approximately 0.0000005 mg.
7 a) 145 200 micrometres; b) 2 272 727 protozoa would have to be put in line.
8 a) False; they are heterotrophic and obtain matter and energy from organic substances they take from other living beings.
b) True.
c) False; firstly, they synthesise organic matter in photosynthesis, then extract the energy from this organic matter through cellular respiration.
d) True.
9 a) Lymphocyte. Blood cell.
b) Skin. Tissue covering.
c) Digestive. A system involved in nutrition.
d) Neuron. Nerve cell.
e) Heart. The organ that pumps blood.
f) Circulatory. A system involved in nutrition.
Moving forward
10 a) Not all cells have the ability to divide. Very specialised cells like neurons have mostly lost that ability.
b) Stem cells can regenerate any type of cell tissue.
c) Stem cells may be used in regenerative therapy to replace other cells that were damaged, and this is how they are used to cure diseases like leukaemia.
REFLECT
In this unit, your students will have studied the environmental characteristics from certain areas of the planet and inside the fridge. This will allow them to begin reflecting on what they’ve learned, which will be supported by the other activities that teach them about the origin, nutritional value and characteristics of some foods.
At anayaeducacion.es, your students have a questionnaire that will help them reflect on their own performance in the tasks offered in this unit. It is advisable to review as a group those aspects in which the students themselves have found room for improvement.
TEST YOUR SKILLS
Your students have, also at anayaeducacion.es, a test that will help them assess their level of acquisition of the skills put into play during the completion of the proposed challenge.
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CHALLENGES THAT LEAVE AN IMPRINT UNIT UNDERSTAND Organising your ideas In your notebook, fill in the spaces in the anayaeducacion.es Living beings by cells Prokaryotic cell Summarising What makes life possible on our planet? heterotrophic nutrition? And between sexual and cells and eukaryotic cells? What is the main difference between eukaryotic animal cells and eukaryotic plant cells? What are the main taxa for classifying living What are the five kingdoms of living beings? What are their main characteristics? What are: a) The kingdoms with prokaryotic cells and the and the kingdoms with beings that don’t have c) The kingdoms with beings that only use beings that only use heterotrophic nutrition, types of nutrition? Interpreting pictures Name the labelled structures. What type of cell is this? 4 Look at the pictures below and answer the a) What kingdom does each living being belong b) Which living beings are unicellular and which are multicellular? Which ones have organs? Which have systems? each living being use? Applying your knowledge Are the following statements about cell components b) Proteins are important because of their structure c) Lipids are carbohydrates that regulate cell activity. of nucleic acids. If 5 kg of animal mass contains approximately in human being with mass of 55 kg? b) How many millions of millions of cells are there c) What the approximate mass of one animal cell? A protozoan measuring 110 micrometres was long would the line be? b) How many protozoa would you need to make a) Fungi use solar energy to make their organic nutrients. Plants don’t use energy from food because they use energy from sunlight. d) All living beings extract the energy they need organ or system? a) Lymphocyte d) Neuron Moving forward can regenerate amputated parts Human beings can’t regenerate an arm or leg, but our bodies like those in our blood, our skin and our liver. But differentiated cells, for example, have lost the ability to make copies of themselves. Stem cells can multiply and transform into are damaged or old. They act as reserves for regenerating different parts of the body. a) Can all the body’s cells regenerate? Give some c) Do some research and describe how stem cells REFLECT In this first unit you learned about the great biodiversity found in fridge and you necessary for life. To reflect on your learning, go to anayaeducacion.es the self-assessment worksheet and complete it. experiment. your competencies.
