Fall 2022 Final Review 2

1.

Define homeostasis:

The ability to maintain stable internal environment despite
changing conditions.

Homeostasis = balance!

2. Why is homeostasis important to organisms?

Chemical reactions, cell
structures, and enzymes only
work in certain environments.

So maintaining
those environments is very
important.

3. Define Osmosis.

Osmosis is the movement of water across a semipermeable
membrane.

4. Is osmosis a form of active or passive transport?

Osmosis is passive because it doesn’t require energy.

Hypotonic, Isotonic, or Hypertonic

Hypo= less solutes
Hyper = more solutes
Iso = same

Water moves from a high concentration to a low
concentration

Hypotonic, Hypertonic, or Isotonic

Hypertonic solution

Water moves out of cell

Cell will decrease in size

Hypotonic solution

Water will move into cell

Cell will increase in size

Isotonic

Water will move in and
out equally

Cell will stay the same

6. Which osmotic condition is best for maintaining homeostasis?

ISOTONIC!

ISO means EQUAL, so makes
sense!

7. Define semipermeable membrane:

A layer that only certain molecules
can pass through.

8. Why is it important for cells
to have a semipermeable
membrane?

To be able to control what is entering and leaving the cell in order to maintain
homeostasis.

9. Passive transport moves from high to low concentration and does not
require energy.

a.Osmosis

B. Diffusion

C.

C. Facilitated Diffusion

10. Active transport moves
from low to high concentration
and requires energy

D. Exocytosis

E. Endocytosis

Type of Transport

Letter in diagram above

Energy Required

Active or Passive

Osmosis

A. Shows movement of water

No - moves with conc. gradient

passive

Endocytosis

E. Uses a vesicle to bring molecules IN to the cell

Active and moves particles IN

(simple) Diffusion

B. Shows movement of gases

No- moves with conc. gradient

passive

Exocytosis

D. Uses a vesicle to get

molecules out of the cell

Active and moves particles

OUT

Facilitated Diffusion

No- moves with conc. gradient

Passive

C. Shows use of protein

channel

​Yes

​Yes

Name of biomolecule

Subunits (monomers)

Function

carbohydrate

Monosaccharide (1 sugar)

Quick energy

Structural support (plant)

lipids

Fatty acid

Long-term energy storage

Cell membrane structure

proteins

Amino acid

Creates traits of organism

Muscle, hair, nails, basic
structure of almost everything

Enzymes (biological catalysts)

Nucleic acids

Nucleotide
Stores and transmits genetic
information

14. What role do enzymes play?

BIOLOGICAL CATALYSTS- They help
activate and speed up chemical reactions in
the body

13. What type of biomolecules are enzymes?

Proteins!

17. The enzyme will only work if the substrate will fit in the enzyme

18. TEMPERATURE & pH must be within a certain range or the enzyme
may denature (change shape) and then it will not work

16. What is the ideal temperature
for the enzyme to the left?

17. What would happen if was at
a temperature of 10 degrees C?

16. What is the optimum or ideal
temperature for the enzyme to the
left?

40 degrees Celsius

17. What would happen if was at
a temperature of 10 degrees C?

It would be too cold and the
enzyme would denature or slow
down