2ND E.S.O.
SCIENCE (Biology) BILINGUAL SUBJECT PROFESSOR NOTES
INDEX PLANTS...............................................................................................................................................3 WHAT IS A FLOWER....................................................................................................................4 POLLINATION...............................................................................................................................4 SPREADING SEEDS......................................................................................................................5 SEEDS.............................................................................................................................................6 A Bean Seed is a Dicot................................................................................................................6 A Corn Seed is a Monocot..........................................................................................................6 HOW PLANTS GROW...................................................................................................................6 GERMINATION..............................................................................................................................7 PHOTOSYNTHESIS.......................................................................................................................8 WHY ARE PLANTS SO IMPORTANT?.......................................................................................9 A BIT OF PRACTICE..............................................................................................................10 PARTS OF A PLANT................................................................................................................11 PLANTS AND FOOD..............................................................................................................12 ECOLOGY.........................................................................................................................................16 WHAT'S AN ECOSYSTEM?.............................................................................................................17 We're All in This Together.............................................................................................................17 Parts and Pieces.............................................................................................................................17 The More the Merrier................................................................................................................18 Getting Along ...........................................................................................................................18 Decomposers.............................................................................................................................18 Scavengers................................................................................................................................19 Chewing It Over........................................................................................................................20 Adaptation and evolution...............................................................................................................20 Adapted for food.......................................................................................................................21 Food chains and food webs ...........................................................................................................21 Life in a Lake............................................................................................................................21 Keeping It All in Balance..........................................................................................................22 Relationships between living things..............................................................................................22 What's the Buzz?.......................................................................................................................22 You scratch my back.................................................................................................................22 Biomes of the world.......................................................................................................................22 Adaptations...............................................................................................................................24 Food chains...............................................................................................................................24 PARTS OF THE ANIMALS.....................................................................................................25
2nd ESO SCIENCE – professor notes
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UNIT 5 PLANTS VOCABULARY •
cell
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seed
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male (adj.)
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female (adj.)
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stick → past stuck [stak], p.p. stuck [stak] → sticky (adj.)
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fall [fol] → past fell, p.p. fallen [folen]
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grow → past grew [gru], p.p. grown
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to be born
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spread [spred] → past spread, p.p. spread
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water → water (verb)
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burst [berst] → past burst, p.p. burst
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soak (verb)
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split (verb) → past split, p.p. split
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root
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leaf → plural leaves
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damp (adj.) ↔ dry
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species [spi∫iz] → plural species
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edible
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WHAT IS A FLOWER A flower is the part of the plant that makes the seeds. The main parts of a flower are the carpels and stamens. These parts are often found in the center of the flower. There are egg cells in the carpel and pollen cells in the stamen. All flowers have four basic parts: sepals, petals, carpels and stamens 1. Different flowers have different numbers and shapes of these parts. All plants produce flowers for the same reason: to make seeds so another plant can grow.
POLLINATION Flower markings are like the landing lights on an airport runway. They guide the bee into the flower's pollen grains. Bees can help flowers make seeds. Bees usually look for pollen and sweet juice. Every flower has pollen, although some flowers don't have sweet juice. The bee's first job is to move pollen from the anther of one flower to the female stigma of another flower. An anther is the male part of a flower that has pollen grains on it. A stigma is the female part of a flower that receives the pollen. In other words, when a bee gets pollen from a flower, the pollen sticks to the bee. The bee goes to another flower and the pollen falls onto the stigma. Most flowers use this pollen to make seeds. Other flowers use their own pollen to make seeds. Each tiny pollen grain grows into a long tube. These are called pollen tubes. They grow until they come to the ovary. The ovary is the section of a flower where the pollen tubes meet. Now a male gamete from the pollen tube joins the egg from the ovary and a seed is born.
1 Stamen ['steimen] → plural stamens or stamina ['stamina]
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SPREADING SEEDS Some seeds are spread by animals' feet. Charles Darwin once grew 80 plants from the mud he scraped off a bird's foot. A seed has everything it needs to produce new plants. No seed can grow with the fruit around it. A seed has to have enough water, good soil, and sunlight. Sometimes people plant them and other times the seeds get planted on their own. People also put seeds in gardens or fields, and water 2 and fertilize the seeds. Birds help some fruits like the cherry by eating the fruit around the seed. The mistletoe's seeds are covered with a sticky substance that sticks to the bird that tries to eat it. The mistletoe's seeds have to land on the soil or they die. Some seeds travel by sailing in the wind. Others float in the water to get to the land. Others hitchike on animals. Some just get blown in the wind. Seeds can also grow in a fruit and drop to the ground. When the seed leaves the fruit or whatever it was in, it's called dissemination. This is one of the most important steps in the seed's life. Some tree seeds drop directly below the parent and die because there is not enough light or minerals for them to grow. The seeds that travel by wind must be light-weight. Some of these seeds have wings, like the maple seed. Some of these seeds have gone 32 miles on a windy day. Another flying seed is the dandelion which gets planted because ants carry the seeds down into their hole.
Mapple seed
Dandelion
The water travelers float away from their parent trees. Coconuts may drift for several months and travel for up to 1,200 miles (2,000 km) before reaching dry land. The coconuts are able to float because of special fibers around their seeds. The hitchhikers are built with spikes. They get stuck to animals and eventually fall off. Some seeds have a sticky substance that makes them stick to animals. Then they travel to another place to grow. Some plants have sacks that explode. The squirting cucumber bursts open and shoot its seeds up to 27 feet (8m) away from the parent plant. The seeds zoom off and may travel as fast as 62 miles (100km) per hour.
2 Put water to the plants
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SEEDS The prefix "di" comes from the Greek word "dis" meaning "two". A Bean Seed is a Dicot Dicots are seeds that have two parts, such as a bean seed. A bean seed that has soaked in water for a day or two has a soft outside covering. This is the seed coat. The seed coat would probably slip off the seed easily. The bean seed has a slit going down the middle of the seed. Inside is a tiny plant called an embryo. The two large parts of the seeds are called cotyledons. They supply the food for the young plant when it's growing. The bean seed has two parts. Therefore, it is a dicotyledon, or dicot for short.
A Corn Seed is a Monocot Monocots are seeds that only have one cotyledon, such as the corn seed. The corn seed does have a seed coat, but it does not slip off as easily as the bean seed. The corn seed will not split like the bean seed. It stays in one piece. One cotyledon surrounds the embryo. It is a lighter color than the rest of the seed. It provides food for the growing plant. The corn seed is a monocotyledon, or monocot. ''Mono'' comes from the Greek word monos, meaning ''one''.
HOW PLANTS GROW Every root grows a mass of tiny hairs near its tip to absorb water from the soil.
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Root hairs are cells. They take water to the main root. Then the main root brings the water to the main plant. The roots also help hold the plant in the ground. The inside of a root has four different parts. The epidermis is the outside part. It is like our skin. It protects the inside parts of the root. Plants take in water from the soil through their roots. The water passes through the vascular rays until it reaches the center of the root, the stele3. This is where the veins are located. The veins are called xylem. They carry the water and food through the plant. Between the epidermis and the stele is the fleshy cortex.
GERMINATION
First the young root appears.
The skin splits and the The main root gets bigger and shoot straightens, pulling grows side roots, and the first the cotyledons with it. leaves appear.
Germination happens when a baby plant is growing. The plant is between the cotyledons. This is a seed. The seed is underground and is collecting nutrients. When a seed starts to grow, we say it germinates. The cotyledons store food for the baby plant inside the seed. When the seed starts to germinate, the first thing to come out is the main root. The skin starts to split and the tiny shoot straightens, carrying the cotyledon[s] with it. The main root gets bigger. Side roots appear and so do leaves. To grow, the seed's growing conditions usually have to be damp, warm, and dark, like springtime soil. A dry seed will stay dormant unless it soaks in some water. Then it will start to germinate. 3 Stele [stili] or [stil]→ plural stelae [stili] or stiles [stiliz] or [stilz]
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PHOTOSYNTHESIS
Animals inhale oxygen and exhale carbon dioxide. Green plants are the only plants that produce oxygen and make food, which is called photosynthesis. Photosynthesis means ''putting together with light.'' This takes place in chloroplasts, which have chlorophyll in them. Chlorophyll absorbs the sunlight. From sunlight, green plants combine carbon dioxide and water to make sugar and oxygen. Green plants use sugar to make starch, fats, and proteins. There are tiny pores called stomata. Carbon dioxide and oxygen enter and leave through the stomata4 respectively.
Do plants sleep? Yes. At night time, plants can not make food, so they shut down by closing their stomata. But plants also need MINERALS and they take these from the soil through their roots. The three main minerals that plants need from the soil are: •
NITRATES
•
PHOSPHATES
•
POTASSIUM
4 Stoma [stouma] (plural stomata [stoumata] or [stoumata]) - tiny pores on the underside of the leaves. Carbon dioxide and oxygen enter and leave the plant through these tiny pores.
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WHY ARE PLANTS SO IMPORTANT? Plants are important to the balance of nature. For animals and people, plants provide food, shelter, useful tools, and products. Plants are very useful to humans. We eat many different types of plants. Some products are made from plants such as shampoos, rubber, paper and camera film. In some countries, fermented sugar cane is used instead of gasoline. Animals use plants in many different ways. They eat many fruits and other plants. Many animals use plants for shelter. Plants also provide animals with protection from predators. The destruction of different plants sometimes leads to animals becoming endangered. The orangutan is an endangered animal. Part of the reason it is endangered is because of the shortage of food. The orangutan eats different types of fruit in the rainforest. The destruction of the rainforest causes the shortage of food. The panda is another endangered species that is partly endangered because of the shortage of food. The panda can eat up to 40 pounds of bamboo each day. The panda is dying out because of the destruction and the dying of the bamboo forests.
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A BIT OF PRACTICE Practice what you have learned on these websites: •
FLASH CARDS, MATCH GAME & CONCENTRATION GAME: http://www.quia.com/jg/546031.html
•
LABELLING GAME (structure of a flower): http://www.missmaggie.org/scholastic/science_eng_launcher.html
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PARTS OF A PLANT 1. Put in order the letter in the boxes to name the parts of the plant: welfor
mest
vasele
toro 2. Read the meaning of these words and – later – find in the picture on the left the part of the plant that they describe: Petals: modified leaves that surround the flower. Sepals: green leaves that lie under the petals. Stigma: upper part of the pistil that receives the pollen. Style: a conduit that allows the pollen to grow to the ovules. Ovary: enlarged portion of the pistil containing the ovules. Anther: top of the stamen which contains the pollen. Filament: stalk of the stamen.
(3) Match the words of the image on the right with their corresponding explanation: a) if you put it into the earth, it becames a new plant b) it contains the seeds c) it produces the fruit d) it absorbs the water from the ground e) it is specialized in photosynthesis f) it transports the fluids and supports the leaves 2nd ESO SCIENCE – professor notes
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PLANTS AND FOOD Search in the text the name of the plants in the pictures. Write the names under the pictures, and classify it into LEAVES, STEMS, ROOTS, FRUITS, SEEDS. Humans consume a remarkable variety of plants and plant parts. Most food plants evolved through selection by many generations of farmers to produce larger fruits, grains and other edible parts. Many foods come from plant roots. Important root crops include carrots, parsnips, beets, sweet potatoes and radishes. Potatoes, which develop underground, technically are stems that are specialized for the storage of starches. Other stems used as food include sugar cane and asparagus. Leafy foods include chard, spinach, lettuce, brussels sprouts and cabbage. All of these look like leaves. However, foods that come from bulbs, such as onions, leeks and garlic, also are made of leaf parts (the enlarged bases of long, slender leaves). Celery stalks actually are the supporting stems (petioles) of leaves. Flowers are not eaten frequently, but cauliflower, broccoli and artichokes all are made up of flowers. Fruits and seeds, which develop after flowers are pollinated, are important food sources. Fruits include familiar foods such as oranges, lemons, apples, peaches, pears, grapes, melons, cherries, plums, tomatoes, green beans and chile peppers. Bananas, figs, eggplant, cucumbers, pomegranates, dates and olives also are fruits. As a general rule, keep in mind that anything with seeds is a kind of fruit. Important seeds that we eat are beans, peas, lentils and chickpeas. All of these are members of the bean, or legume, family. Many nuts consist of seeds or parts of seeds. Examples are almonds and peanuts. Grains, considered to be among the first cultivated crops, are the small, dry fruits of members of the grass family. Grains look and behave very much like individual seeds. The commonly cultivated food grasses are called cereals. Major grain crops include barley, oats, rice, rye, sorghum, wheat and corn (maize). Rice, probably the most important grain, is the primary food source for more than 1.6 billion people. (1)
(2)
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(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
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(16)
(17)
(18)
(19)
(20)
(21)
(22)
(23)
(24)
(25)
(26)
(27)
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Which food coming from plants have you eaten during the last week? _______________________________________________________________ _______________________________________________________________ Which parts of the plants have you eaten during the last week? _______________________________________________________________ _______________________________________________________________ Which are your favourite seeds as a food? _______________________________________________________________ Write some edable fruits that are not sweet. _______________________________________________________________ How often do you eat fruits? _______________________________________________________________ Some foods grow underground, but are not real roots. Can you write the name of some of them? _______________________________________________________________ Which plants can you put in a salad? _______________________________________________________________ You are going to make a vegetable soup. Which ingredients can you put? _______________________________________________________________ Which vegetables can you put in an omelette? _______________________________________________________________ Complete this table, describing the vegetable foods of the left: Shape and size
Does it have Taste (if seeds or shell? any)
Colours inside
Colours outside
Radishes Potatoes Peanuts Grapes Beans Eggplant
What ● ● ● ● ● ●
can it be? White in the centre and with some green leaves arround. ____________ Small, green and with a hard seed inside. _____________ Round, brown and very little. ______________ Green big leaves with white stems. ______________ Orange and grows underground.____________ Sweet, green and with some little seeds. ___________
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UNIT 6 ECOLOGY VOCABULARY •
nature
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soil
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balance (verb & noun)
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nutrients
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role
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die (verb)→ dead
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interact (verb) → interaction
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depend on (verb)
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break down (verb) → past broke, p.p. broken
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chew (verb)
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grind up (verb)
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swallow (verb)
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digest (verb) → digestion
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hunt (verb)
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survive (verb)
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sick (adj)
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disease
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take in → past took, p.p. taken
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excrete (verb) → excretion
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decompose (verb) → decomposer
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rot (verb)
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behave (verb) → behavior
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beak = bill
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gene mutation
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breed (verb)
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offspring
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WHAT'S AN ECOSYSTEM? We're All in This Together Everything in the natural world is connected. An ecosystem is a community of living and non-living things that work together. Ecosystems have no particular size. An ecosystem can be as large as a desert or a lake or as small as a tree or a puddle. If you have a terrarium, that is an artificial ecosystem. The water, water temperature, plants, animals, air, light and soil all work together. If there isn't enough light or water or if the soil doesn't have the right nutrients, the plants will die. If the plants die, animals that depend on them will die. If the animals that depend on the plants die, any animals that depends on those animals will die. Ecosystems in nature work the same way. All the parts work together to make a balanced system!
Parts and Pieces What are the major parts of an ecosystem? An eosystem includes soil, atmosphere, heat and light from the sun, water and living organisms. Soil is a critical part of an ecosystem. It provides important nutrients for the plants in an ecosystem. It helps anchor the plants to keep them in place. Soil absorbs and holds water for plants and animals to use and provides a home for lots of living organisms. The atmosphere provides oxygen and carbon dioxide for the plants and animals in an ecosystem. The atmosphere is also part of the water cycle. Without the complex interactions and elements in the atmosphere, there would be no life at all! The heat and light from the sun are critical parts of an ecosystem. The sun's heat helps water evaporate and return to the atmosphere where it is cycled back into water. The heat also keeps plants and animals warm. Without light from the sun there would be no photosynthesis and plants wouldn't have the energy they need to make food. Without water there would be no life. Water is a large percentage of the cells that make up all living organisms. In fact, you may have heard that humans can go longer without food than they can without water. It's true! Without water all life would die. In addition to being an important part of cells, water is also used by plants to carry and distribute the nutrients they need to survive.
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The More the Merrier A healthy ecosystem has lots of species diversity and is less likely to be seriously damaged by human interaction, natural disasters and climate changes. Every species has a niche in its ecosystem that helps keep the system healthy. We are learning about new species every day, and we are just figuring out the roles they play in the natural world. By studying and maintaining biodiversity, we help keep our planet healthy. If you want to learn the difference between niche, habitat and ecosystem, visit this page: http://www.backyardnature.net/econiche.htm
Getting Along Ecosystems have lots of different living organisms that interact with each other. The living organisms in an ecosystem can be divided into three categories: producers, consumers and decomposers. They are all important parts of an ecosystem. Producers are the green plants. They make their own food. Consumers are animals and they get their energy from the producers or from organisms that eat producers. There are three types of consumers: herbivores are animals that eat plants, carnivores are animals that eat herbivores and sometimes other carnivores and omnivores are animals that eat plants and other animals. The third type of living organism in an ecosystem are the decomposers. Decomposers are plants and animals that break down dead plants and animals into organic materials that go back into the soil. Which is where we started!
Decomposers When plants and animals die, they become food for decomposers like bacteria, fungi and earthworms. Decomposers or saprotrophs recycle dead plants and animals into chemical nutrients like carbon and nitrogen that are released back into the soil, air and water. Bacteria can be found everywhere. They live in the water, in the air and on land. Bacteria are prokaryotic, which means they don't have a nucleus or a mitochondrea like other single-celled organisms. Bacteria are among the smallest forms of life on Earth. In fact, you may have up to 100 million bacteria in your body right now! Some bacteria are harmful and cause diseases like typhoid and cholera. Other bacteria are helpful. You have bacteria in your digestive tract that kills more hamful bacteria. Some ruminants like moose, sheep, and deer have bacteria in their stomachs that 2nd ESO SCIENCE – professor notes
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help them digest plants. Bacteria help turn milk into cheese, cucumbers into pickles and cabbage into sauerkraut. Other bacteria help decompose dead plants and animals. Fungi like mushrooms, mildew, mold and toadstools are not plants. They don't have chlorophyll so they can't make their own food. Fungi release enzymes that decompose dead plants and animals. Fungi absorb nutrients from the organisms they are decomposing! There are over 50,000 species of fungi. Most fungi are very, very small! There are many fungi that are helpful. Penicillin and other antibiotics are made from fungi. Some fungi like mushrooms, truffles and yeast are edible or used in making food. Other fungi are harmful. There are over 1,800 species of earthworms. They are hermaphroditic, which means they have both male and female organs. Earthworms need moist environments to survive. If they dry out, they have trouble burrowing into the soil and they will die. Earthworms eat dead plants and animals. When they eat, they also take in soil and tiny pebbles. They take in nutrients from microorganisms in the material they ingest. Earthworms then excrete wastes in the form of casts. Casts are rich in nutrients like nitrogen, phosphorus, and potash. In addition to breaking down organic materials and adding nutrients to the soil, earthworms also help loosen the soil so air can circulate. This helps plants grow.
Scavengers Cockroaches are scavengers that eat all kinds of materials including paper, clothing and dead animals and plants. They are adapted to live in almost any environment and have been on earth longer than any other winged insect, over 340 million years. There are 3,500 species of cockroaches in the world. There are 57 different species found in North America. Cockroaches like warm, humid, dark environments. They usually feed at night. Cockroaches have flattened bodies that make it easy for them to crawl into small spaces. Long antennae5 on the front of their heads help them feel their way around. Cockroaches have an interesting warning system. They have appendages on their underside called cerci. The cerci are very sensitive and help cockroaches detect vibrations and movement so they can scoot into a safe place. Most species of cockroaches live in the woods and feed on dead plants, but some species like the American and German cockroaches, often live in peoples' homes and feed on kitchen scraps and garbage. Believe It or Not, Roaches can live for up to a week without their heads. After a week they will die because without their heads they can't drink water. 5 Antenna → plural antennae (antenai) refers to insects and crustaceans. Antenna → plural antennas refers to aerial.
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The turkey vultures is a scavenger. It only eats carrion6. It soars over the land looking for dead animals. It has excellent eyesight and a keen sense of smell that helps it locate rotting meat. Because it doesn't hunt and kill it food, its legs and claws are weaker than that of most birds. The turkey vulture has a bald head. This helps keep dead meat along with the bacteria it carries from collecting in the vulture's feathers while it is digging into an animal carcass 7. The turkey vulture also urinates on its legs. It's urine cools the vulture and the acids in the urine kill any bacteria that collected on the vulture's legs when it was stepping in the carcass.
Chewing It Over Some herbivores have digestive systems to help them get the most out of the plants they eat. Animals like sheep, moose, white-tailed deer and cows have a special stomach called a rumen where microorganisms break down cellulose. Animals with a rumen are called ruminants. Ruminants swallow their food and then regurgitate it and chew on it again to break down the cellulose in the plant. Once the cellulose is broken down, the food returns to the stomach where it is digested. When you hear that an animal is chewing its cud, it is rechewing food that it had already swallowed!
Adaptation and evolution Animals come in all shapes and sizes, and they live in all kinds of environments. An environment is everything that surrounds and affects how an animal lives. All animals have adaptations that fit their environments. An adaptation is a part of an animal's body or way that an animal behaves that helps it survive. All organisms have adaptations that help them survive and thrive. Some adaptations are structural. Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations. Adaptations are the result of evolution. Evolution is a change in a species over long periods of time. Adaptations usually occur because a gene mutates or changes by accident! Some mutations can help an animal or plant survive better than others in the species without the mutation. For example, imagine a bird species. One day a bird is born with a beak that is longer than the beak of other birds in the species. The longer beak helps the bird catch more food. Because the bird can catch more food, it is healthier than the other birds, lives longer and breeds more. The bird passes the gene for a longer beak on to its offspring. They also live longer and have more offspring and the gene continues to be inherited generation after generation. Eventually the longer beak can be found in all of the species. This doesn't 6 Decomposing flesh 7 Dead body of an animal
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happen overnight. It takes thousands of years for a mutation to be found in an entire species. Over time, animals that are better adapted to their environment survive and breed. Animals that are not well adapted to an environment may not survive. The characteristics that help a species survive in an environment are passed on to future generations. Those characteristics that don't help the species survive slowly disappear.
Adapted for food Carnivores are predators. They hunt and eat other animals to survive. Mammals that are carnivores have sharp teeth adapted for ripping meat from a carcass. Carnivores like the wolf have large, powerful jaws that help bring down large animals like deer. The bobcat and cougar have powerful paws with sharp claws that help them catch prey. Meat-eating birds like hawks and owls have keen eyesight that makes it easier for them to spot prey. They have sharp talons to catch prey and curved beaks to tear up meat. All of these adaptations help these carnivorous birds catch and eat their prey. Herbivores have teeth adapted to chewing plants. Their big molars are designed to help them grind up leaves, seeds and twigs. What did you have to eat today? If you are like most humans, you probably had meat and plants! Humans are omnivores too! Our teeth are designed to eat both meat and plants. Our front teeth help us rip into meat and bite into fruits and vegetables. Our molars help us grind up meat and chew fruits and vegetables. Many omnivorous animals also have teeth that help them eat both plants and animals.
Food chains and food webs Learn about the food chain and the life cycle clicking on this link: http://msnucleus.org/membership/storybooks/foodchain.html
Life in a Lake In a lake ecosystem, the sun hits the water and helps the algae grow. Algae produces oxygen for animals like fish, and provides food for microscopic animals. Small fish eat the microscopic animals, absorb oxygen with their gills and expel carbon dioxide, which plants then use to grow. If the algae disappeared, everything else would be impacted. Microscopic animals wouldn't have enough food, fish wouldn't have enough oxygen and plants would lose some of the carbon dioxide they need to grow. 2nd ESO SCIENCE – professor notes
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Can you represent all these relationships in an arrow diagram?
Keeping It All in Balance The carnivore's niche in the community is to help control populations. Very young, old or sick prey are most vulnerable to predators. Without predators, populations of animals like mice and deer would grow too large and sick animals might spread disease to other animals. By catching prey, carnivores help keep a balance in communities between producers and consumers.
Relationships between living things What's the Buzz? Honey bees take nectar from flowers for energy. When bees gather nectar, they pick up pollen on their fuzzy bodies. As bees travel from flower to flower gathering nectar, they leave some pollen behind. Pollen left behind pollinates flowers and helps these plants reproduce. Bees have a symbiotic relationship with the flowers they pollinate. A symbiotic relationship is one that benefits both living things; for example, bees get the nectar they need and the flowers get pollinated!
You scratch my back Most species of legumes (alfalfa, lentils, beans, chick-peas, peas, peanuts) and bacteria have a symbiotic relationship. A symbiotic relationship is one in which two species benefit each other. The roots of most of these plants have a nitrogen-fixing bacteria, rhizobium, that changes nitrogen in the air into the nitrates the plants need to synthesize proteins. Rhizobium bacteria invade the root hairs of the plants. They multiply and help root nodules grow. Then the bacteria changes free nitrogen, or the nitrogen from the air, to nitrates. Species in this order leave some of the nitrates in the soil, which can help other plants grow.
Biomes of the world Choose a partner and investigate about one of these biomes. Expose your work in class. Here are some sources of information: http://www.mbgnet.net/ http://www.ucmp.berkeley.edu/exhibits/biomes/index.php You also have information and activities about biomes in this page: http://www.nclark.net/CommunitiesBiomes.html
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PRACTICE WHAT YOU'VE LEARNED8 •
Ecosystems quiz:
http://www.softschools.com/quizzes/science/ecosystems/quiz460.html •
Food chain quiz:
http://www.ecokids.ca/pub/eco_info/topics/frogs/chain_reaction/index.cfm •
Build a food web:
http://teacher.scholastic.com/activities/explorer/ecosystems/be_an_explorer/ma p/form_wildcats.htm# http://www.harcourtschool.com/activity/food/food_menu.html •
Biome mission:
http://earthobservatory.nasa.gov/Experiments/Biome/ •
Test about biomes:
http://www.quia.com/quiz/247029.html
8 Learn can be regular (learned) or irregular (learnt)
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Adaptations 1.- Associate each adaptation with the corresponding animal and the environment to which it is adapted (there may be more than one possibility) ANIMAL
ADAPTATION
ENVIRONMENT
camel
has thick skin and lots of fat
predators
dessert turtle
has long eyelashes and nostrils that can be closed
low temperatures
dessert fox
has kidneys that restrict water loss
few water
lizard
has a tail that breaks off readily
high temperat.
penguin
is active just early in the morning and late in the evening
lot of sand
Food chains 2.- Explain what these animals eat, and classify them into herbivores, carnivores and omnivores. Note that the arrows are drawn from food source to food consumer. In other words, you can substitute the arrows by the words "is eaten by"
3.- Classify the living beings in this food web as producers, primary consumers, secondary consumers and tertiary consumers. Choose four of them and form a food chain.
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PARTS OF THE ANIMALS 1. Search in this picture the parts of the fish that help it to: a. b. c. d. e.
to to to to to
protect from predators detect movement and vibration in surrounding water breathe move along steer and balance
2. Match the numbers of the picture with the following names of the parts of a bird: Forehead - Eyebrow - Back – Bill - Tail - Throat - Breast - Foot – Leg - Shoulder Wing – Flank – Neck. For help, you can check with the picture on the right.
3. Put the names of the parts of an insect in the boxes: 6 legs forewing hindwing antenna abdomen torax compound eyes
2nd ESO SCIENCE – professor notes
page 25