Chapter 7

Question 1

What is cell theory?

Answer 1

• The theory that cells make up the fundamental structure of all living organisms
• All cells come from preexisting cells
• Cells are the basic unit of life

Question 2

What are the characteristic of prokaryotes and eukaryotes?

Answer 2

• Prokaryotes- Contains DNA in cytoplasm (no nucleus), simple, small, first
• Eukaryotes- Contains DNA in nucleus, complex, specialized

Question 3

What structures do all cells have?

Answer 3

Ribosomes, DNA, cell membrane, cytoplasm.

Question 4

What structures do plant cells have that animal cells do not?

Answer 4

Chloroplasts and the cell wall

Question 5

What are the main functions of the cell membrane and cell wall?

Answer 5

To support, protect, and shape the cell. (cell membrane regulates what enters and exits the cell)

Question 6

What does it mean that a cell membrane as a “lipid bilayer”?

Answer 6

Cell membranes are made of lipid bilayers, which give the cell membranes a flexible structure that forms a strong barrier between the cell and its surroundings.

Question 7

Why are cell membranes described as a “fluid mosaic” of different molecules?

Answer 7

It is made up of many different molecules that all piece together to form the lipid bilayer

Question 8

What are the two functions of the cytoskeleton?

Answer 8

To support and shape the cell

Question 9

Solute, Solvent, Solution?

Answer 9

Solute- thing being dissolved
Solvent- thing doing the dissolving
Solution- when a solute is dissolved in a solvent

Question 10

What is the main difference between diffusion, osmosis, facilitated diffusion, and active transport?

Answer 10

Diffusion- the movement of many substances across the cell membrane
Osmosis- Diffusion specified to water
Facilitated diffusion- Aided diffusion (protein channels)
Active transport- the movement of materials against a concentration difference. Uses energy.
Passive- Does not use energy

Question 11

What is the main difference between diffusion and active transport?

Answer 11

Diffusion- no energy

Active transport- energy

Question 12

What is equilibrium?

Answer 12

Equilibrium- the point at which the concentration of a substance is equal on both sides of the cell membrane. Movement does not stop when equilibrium is reached.

Question 13

What is the difference between iso-, hyper- and hypotonic solutions?

Answer 13

Isotonic- the same amount of solute on both sides
Hypertonic- More of a solute on one side
Hypotonic- Less of a solute on one side
ALL TERMS ARE COMPARISONS

Question 14

What is the difference between phagocytosis and pinocytosis?

Answer 14

Phagocytosis- Engulfment of food

Pinocytosis- Engulfment of water

Question 15

What is cell specialization?

Answer 15

Different cells have different jobs

Question 16

What are the 4 levels of organization in multicellular organisms? Simple to complex.

Answer 16

Cell
Tissue
Organ
Organ system

Question 17

Which salt solution is more concentrated, Solution A, which contains 18g of salt in 6 L of water, or Solution B, which contains 24g of salt in 12 L of water?

Answer 17

Solution A- it has 3g of salt per liter versus 2g of salt per liter in Solution B.

Question 18

What would happen to a sample of your red blood cells if they were placed into a hyptonic solution? Explain your prediction.

Answer 18

The hypotonic solution would try to dilute the cell by entering it. The cell would swell and possibly burst.

Question 19

Would you expect skin cells to contain more or fewer mitochondria than muscle cells?

Answer 19

I would expect skin cells to contain fewer mitochondria than muscle cells because muscles use more energy.

Question 20

The pancreas, an organ present in certain animals, produces enzymes used elsewhere in the animals’ digestive systems. Which type of cell structure(s) might produce those enzymes? Explain your answer.

Answer 20

I think ribosomes would be the structure that makes these enzymes because that is what ribosomes do- make enzymes.

Question 21

As waste chemicals build up in a cell, homeostasis is threatened. State how diffusion helps maintain homeostasis.

Answer 21

Diffusion brings in nutrients and takes out waste. Without diffusion, waste would build up in the cells and cause buildup. The cell would die.

Question 22

In Chapter 2, we learned about four categories of carbon compounds called the “molecules of life”. Explain where some of those compounds are found in a typical cell

Answer 22

Lipids- In the cell membrane
Carbohydrates- In the cell membrane
Nucleic Acid- In the nucleus
Proteins- In the ribosomes