Grade 7 Science
Cells: Life Structures
Chapters 8 Study Guide
Section 1: Living Things
 Six characteristics of all living things:
1. made of cells
2. grows and develops
3. interacts with environment- a stimulus (action) triggers a response (reaction)
4. maintains homeostasis
5. uses energy
6. reproduces
Key terms: organism, cell, homeostasis
Section 3: Cell Structure
 The microscope led to the development of the cell theory
 Who discovered the microscope?
 Who first discovered cells?
 Matthias Schleiden discovered that plants have cells and Theodore Schwann discovered
that animals have cells
 What was Rudolph Virchow’s contribution to the cell theory?
 Three parts of the cell theory:
1. all living things are made of cells
2. the cell is the basic unit of life
3. all cells come from other cells
 Two groups of cells:
1. Prokaryotic- contains structures without membranes
2. Eukaryotic- contains organelles; plant and animal cells
 What cell parts do prokaryotic and eukaryotic cells have in common?
 Important cell parts/organelles:
o Cell membrane
o Cell wall
o Nucleus
o Endoplasmic reticulum
o Ribosome
o Chloroplasts
o Mitochondrion
o Golgi body
 Animals cells do NOT have cell walls or chloroplasts- only plant cells do
 Animal cells have lysosomes- plant cells have chloroplasts
 Animal cells have multiple, small vacuoles and plant cells have one, large vacuole
 What are the five levels of organization in all living things?
Key terms: cell theory, nucleus, cell membrane, cell wall, cytoplasm, organelle,
mitochondrion, chloroplast, vacuole, lysosome, endoplasmic reticulum, ribosome, golgi
body, tissue, organ, organ system
Grade 7 Science
Cells: Life Structures
The Microscope- NOT IN TEXTBOOK
 What are the only two parts of a microscope one should hold when carrying this
instrument?
 There are three objective lenses:
1. Low – only use coarse adjustment knob
2. Medium- use fine adjustment knob
3. High- use fine adjustment knob
 Why should you put the cover slip over the slide at an angle?
Possible short answer questions:
1. Cell theory
2. Eukaryotic cells