Download Cells Study Guide Answers

Name: __________________________ Homeroom: _____________________ Date: __________________
EARTH’S SPECIES
1. Describe where most life is found on earth. Compare this to an apple.
Most life is found in a small layer of the earth, from just below the surface to the lower part of the atmosphere.
2. What is a species?
A group of organisms that have the same characteristics and are able to produce offspring that can reproduce.
3. No matter how many different organisms there are on Earth, they are all made up of what?
cells
DISCOVERY OF CELLS
4. What did Hans Janssen and his son, Zacharias invent?
Compound microscope
5. How did they do this?
Put two lenses together at the opposite ends of a tube
6. What did Robert Hooke look at under the microscope?
Cork cells
7. What did Hooke "see"? What did he call what he saw? Provide as much detail as you can.
“a great many little boxes” separated by walls. He called them “cells”.
8. Your book explains that what Hooke saw were not considered living cells. If so, what part of the cell was he
looking at?
Cell wall
9. How much was Hooke’s microscope able to magnify objects?
30 times
10. How much can today’s best compound microscopes magnify objects?
1500 times
11. List and define the 5 basic parts of a compound microscope.
a. Objective lens – magnifies the image on the slide
b. mirror – reflects light from another source through the image being observed
c. eyepiece – allows you to see the object, and also magnifies the image, usually 10 times.
d. adjustment knobs – allow you to focus the image
e. stage – holds a slide containing the object to be viewed
12. How does a compound microscope allow people to see cells (see page A12)?
Opening in the stage allows light to pass through the object to be viewed. The light then passes through the
magnifying lenses.
13. Today most scientists use a different type of microscope. What kind do they use?
Electron microscope
14. How much do these new microscopes magnify objects?
Up to a million times (or more)
CELL THEORY
15. What are the two main points of the Cell Theory?
The cell is the basic unit of all living organisms. Only living cells can produce new living cells.
ANIMAL CELLS
1. Given a diagram of an animal cell, be able to identify its structures.
a. Nothing to do for the study guide. Just be able to do this for the test.
2. Define nucleus.
Part of the cell that controls activities of other cell parts
3. Define chromosome.
String-like structure in a cell nucleus that carries information controlling all the cell’s activities.
4. What kind of processes do the chromosomes control?
How fast the cell grows or when it reproduces, etc…
5. Define cell membrane.
Thin outer covering that holds a cell together
6. What does the cell membrane “allow”?
Allows certain substances to enter and leave the cell.
7. What does the cell membrane control?
The cell membrane controls what goes in and out of the cell.
8. What does the cell membrane allow to enter the cell?
Oxygen and other materials
9. What does the cell membrane allow to exit the cell?
Carbon dioxide and wastes
10. Define cytoplasm.
Clear, jellylike material that fills the space between the cell membrane and the nucleus
11. What is cytoplasm mostly made up of?
water
12. Explain the importance of this substance (from #11).
Cells must have water to survive and carry out necessary activities. Body cells are 2/3 water, and you can’t
survive more than 4 days without water.
FUNCTIONS OF CELL PARTS
13. What is an organelle?
Tiny structure in the cytoplasm of a cell that performs a special job
14. Define mitochondria.
Organelles where food and oxygen react to release energy
15. What 2 things react to release energy for the cell?
Food and oxygen
16. What nickname is given to the mitochondria?
Powerhouses
17. Do all cells have the same number of mitochondrion? EXPLAIN.
No – some cells need more energy so they need more mitochondria. For example, a muscle cell would need
more energy than a skin cell.
18. Define vacuole.
Saclike organelle used for storing materials
19. What are three things that are stored in animal vacuoles?
Nutrients, water, waste
20. Are animal vacuoles small? Are there a lot of them?
They are small and there are many.
21. Define endoplasmic reticulum.
Organelle that transports materials inside the cell
22. Define ribosome.
Organelle that puts together proteins for the cell
23. Which organelle are there a lot of ribosomes attached to?
Endoplasmic reticulum
PLANT CELL DIAGRAM
1. Given a diagram of a plant cell, be able to identify its structures.
a. Nothing to do for the study guide. Just be able to do this for the test.
2. How do the vacuoles differ in animal cells and plant cells?
Many small vacuoles in animal cells. One large vacuole in plant cells.
3. What happens with the large vacuole in the plant cell? What does this pressure do?
It fills with water and pushes the cytoplasm against the cell membrane. This pressure helps to keep the cell firm.
4. Define chloroplasts.
Organelle that makes sugars, using carbon dioxide, water, and the energy from sunlight
5. What do chloroplasts look like and where do you find them?
Green, egg shaped, scattered throughout the cytoplasm
6. Define chlorophyll.
Green substance in the chloroplasts that traps energy from the sunlight
7. Define cell wall.
Tough, nonliving material that acts like an outside skeleton for each plant cell
8. What three things does the cell wall give the cell?
Support, strength, shape
1. Skin cells
Cover and protect your body. They keep harmful organisms from entering your body. Live 19-34 days.
2. muscle cells
help you move, to push food through your digestive system, and keep your heart beating. Long, thin shape
allows them to contract to move parts of your body. Can live the lifespan of the organism.
3. nerve cells
long, narrow, carry messages throughout your body, live for the lifetime of the individual
4. red blood cells
live about 120 days, carry oxygen to your body cells and carry wastes away
5. white blood cells
live from 10 hours to over a year – protect you from disease
6. What is the job of white blood cells?
Find and destroy invaders
7. How are white blood cells shaped?
irregular
8. What does this shape allow the white blood cells to do?
To slip through the thin walls of blood vessels and move among your muscle cells and other tissues
9. Are all cells the same shape?
No – their shape depends on their function
10. Explain whether or not as you grow, do your cells get bigger or does your body produce more cells?
Cells do not get bigger – you get more cells
11. What are “among the smallest of cells”?
bacteria
12. What is one of the longest cells (according to page A29 in your book)?
Nerve cell in a giraffe that goes from its hip to its toe
OTHER DIFFERENCES IN STRUCTURE
13. Explain why a muscle cell in your leg would have more mitochondria than a bone cell would?
Muscle cell needs more energy – mitochondria produce energy for the cell
14. Describe two structures that some cells have to help them move around.
Cilia – tiny hairs that move back and forth
Flagella – tail that helps them move