7th Grade Chapter 2 by Jennifer Erickson

Chapter 2

Name: ___________________________ Period: ______

Section 1: What is Life? Pages 34 - 40 Characteristics of Living Things All living things have ______________________________________________________ ________________________________________________________________________ ________________________________________________________________________

Cellular organization  Cells are the _____________________________________________________  They are so ______________ that you need a ____________________ to see them.

–Unicellular organism = ________________________________ (ex: ________________) –Multicellular organism= composed of _____________________ that are specialized to do _______________________

Chemicals of Life  Most abundant chemical in living things is ____________________  Other chemicals include:

–_____________________________________ (cell’s energy source) –_____________________________________ (building materials of cells) –_____________________________________ (cell’s genetic material) 1

Energy Use  Living organisms need ___________________________________  Example: your brain cells are at work as you read and write… they need energy do to this

Respond to Surroundings  Stimulus = _______________________________________________________________ ________________________________________________________________________ a. Examples: _________________________________________________  Response = ______________________________________________________________ a. Example: ____________________________________

Growth and Development  Growth = ________________________________________________________  Development = ___________________________________________________________ ________________________________________________________________________

Reproduction  ________________________________________________________________________

Life Comes From Life  Living things __________ from _______________________ through ________________  An OLD theory was SPONTANEOUS GENERATION where ______________________ ________________________________________________________________________

THIS DOES NOT HAPPEN!!!! 2

Francesco Redi

• 1600’ s Italian doctor • In his experiment he showed that _______________________________________________ ___________________________________________________________________________

• See pages 36 in your book for more info on his experiment (take some notes here)

Louis Pasteur

• 1800’ s French chemist • He demonstrated that bacteria _________________________________________________ • See page 37 in your book for more on his experiment (take some notes here)

Needs of Living Things • Need: 1. _____________________ 2. _____________________

• ______________________________ make their own food (plants) • ______________________________ obtain energy by feeding on others (us) 3. _____________________

• Everyone needs a place to live 4. _____________________ (We also call this: ________________________) 3

Homeostasis

• The ability to keep the conditions ____________________________________ or the same even when __________________ in their _________________________________________

• For example: What type of clothes do you wear in the summer versus the middle of winter? Section 2: Classifying Organisms, Pages 42 - 49

Classification

• The process of __________________________________________________________ • Used to __________________ living things into __________ so that they are easier to study • Taxonomy = _______________________________________________________________ Binomial Nomenclature • The _____________________________________________ of classifying organisms • ____________________________ created this system in the 1750’ s and it is still used today Scientific Name

• Made up of an organism’ s _____________________________________ • For example: –Humans are ________________________________ –House cats are Felis _______________________ –Pumas are Felis _______________________

Levels of Classification

How can I remember all the levels?

There are 8 levels of classification

1. _______________________

2. _______________________

3. _______________________

4. _______________________

5. _______________________

6. _______________________

6. _______________________ 7. _______________________

7. _______________________

8. _______________________

Domains

• Today we use a three-domain system of classification • 1. ______________________________ • 2. ______________________________ • 3. ______________________________ Domain Bacteria • Prokaryotes –organisms whose cells ________________________ (control center of a cell) • _________________________________ Domain Archaea • Unicellular ______________________________ • They live in _______________

_______________ conditions 5

Domain Eukarya

• Eukaryotes = organisms with cells that ______________________________ • Classified into four Kingdoms • 1. ______________________________ • 2. ______________________________ • 3. ______________________________ • 4. ______________________________ Section 3: Cells, Pages 50 -57 Cells

• The _____________________________________________________________________ • Cells form the parts of an _____________________ and carry out all of the _____________ _____________________

First Observations of Cells

• Cells _____________ be observed without the use of ________________ • Microscope = ___________________________________________ –A ________________ microscope has only __________________________ –A ________________________________ has more than one lens Robert Hooke • One of the first people ever to _________________________________ • Observed cork and noticed that it had many “ _____________________”or _____________ 6

Anton van Leeuwenhoek • Used a _____________________to observe lake water, scrapings from teeth, and rain water • Viewed _______________________________________________ Cell Theory

• A widely accepted explanation of the relationship between cells and living things • 1. _______________________________________________________________________ • 2. ______________________________________________________________________ • 3. _______________________________________________________________________ Light and Electron Microscopes

• The _____________ in light microscopes magnify an object by ______________ ______________ that passes through them

Compound Microscopes

• Uses more than one lens • Can magnify objects _____________________________________________ • Total Magnification = ________________________* ________________________ Electron Microscopes • Use a ________________________________ instead of ____________________ to produce a magnified image

• Very advanced and very expensive 7

Section 4: Looking Inside Cells, Pages 60 - 67 Cells

• _________________________________________________________________________ • Made up of ________________________________ –Organelles are _______________________ that carry out _____________________ Cell Organelles (take a look at

the cell comparison sheet)

• Cell Wall = ________________________________________________________________ –Helps to ________________ and ________________ the cell • Cell Membrane = ___________________________________________________________ –Found in both ________________ and ________________ • Nucleus = _________________________________________________________________ • Made up of: –Nuclear Envelope = ________________________________________ –Chromatin = ________________________________________ –Nucleolus = ________________________________________ • Cytoplasm = _______________________________________________________ • Mitochondria = _____________________________________________________________ • Endoplasmic Reticulum = ____________________________________________________ •Ribosomes = _________________________________________

• Golgi Bodies = _____________________________________________________________ • Chloroplasts = Found only in _________. ________________________________________ •Vacuoles = _________________________________ 8

• Lysosomes = _________________________________________________ Specialized Cells

• Cells = ___________________________________________ • Tissues = ___________________________________________ • Organs = ___________________________________________ • Organ systems = ____________________________________________________________ • Organisms = ___________________________________________

____________

___________

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