Weekly Quiz 3

Question 1

Assume a growth factor from outside a cell tells the cell to divide. The growth factor cannot diffuse through the plasma membrane and there are no transport proteins for that growth factor. What can you deduce about the growth factor receptor?

Answer 1

The growth factor receptor must be at least partly exposed to the fluid outside a cell.
The growth factor receptor must be connected to the inside of the cell.
The growth factor receptor must change shape when it binds to the growth factor.

Question 2

When treating type 1 diabetes mellitus with insulin injections, what is the role of a glucose meter?

Answer 2

A glucose meter serves as a sensor in a negative feedback loop

Question 3

If a concentration gradient is held constant, what is the most direct way to change the rate of osmosis across a cell membrane?

Answer 3

By changing the concentration of aquaporins in cell membranes

Question 4

The portion of a cell membrane that forms the core (inside) of a lipid bilayer consists primarily of

Answer 4

Lipid

Question 5

Mitochondria are most closely associated with

Answer 5

ATP Synthesis

Question 6

The primary purpose of a buffer is to

Answer 6

Maintain the hydrogen ion concentration of a solution

Question 7

The production of mRNA from a gene is called

Answer 7

Transcription

Question 8

By which of the following methods does a cell control the rate of a chemical reaction?

Answer 8

By separating reactants from each other
Through the controlling the activity of enzymes

Question 9

Sodium is moved from the inside of a cell to the outside of a cell by

Answer 9

Active transport

Question 10

Glucose moves across the plasma membrane of a fat cell by

Answer 10

Facilitated diffusion

Question 11

In human cells, a concentration gradient usually pushes potassium

Answer 11

Out of a cell

Question 12

Humans have proteins that change shape in the presence of blood glucose.

Answer 12

True

Question 13

How would adding acid to a non-buffered solution be most likely to affect protein structure?

Answer 13

Adding acid would disrupt the secondary and tertiary structure of the protein

Question 14

If blood sodium dropped to dangerously low levels, cells in the body would

Answer 14

Swell and possibly pop

Question 15

If a red blood cell is placed in a very dilute solution, what will happen

Answer 15

The cell will burst

Question 16

When treating type 1 diabetes mellitus with insulin injections, where would we find the control center in the feedback loop?

Answer 16

Our brain

Question 17

Transcription is the name for a process in which

Answer 17

A DNA template is used to form a complimentary strand of messenger RNA

Question 18

Sources of chemical potential energy in the body include

Answer 18

Carbohydrate
Protein

Question 19

Insulin receptors are glucose transporters

Answer 19

False

Question 20

Moving sodium out of a cell

Answer 20

Requires the input of energy

Question 21

If all GLUT4 transporters were destroyed, would injected insulin lower blood glucose?

Answer 21

No

Question 22

A box of dried pasta can sit on the shelf indefinitely without breaking down, but when we eat the pasta, starch is broken down into water and CO2. Energy stored in the bonds is released. The reason pasta breaks down in our bodies is that

Answer 22

Enzymes in our bodies lower the amount of energy required for chemical reactions to move forward

Question 23

How do forces act on sodium in resting cells?

Answer 23

Electrical gradient pushes in; concentration gradient pushes in

Question 24

When blood glucose climbs, the sensor for the change is in the

Answer 24

Pancreas

Question 25

If pancreatic beta cells are destroyed, will injected insulin lower blood glucose?

Answer 25

Yes

Question 26

In type 1 diabetes mellitus, which of the following are compromised?

Answer 26

The sensor
The control center

Question 27

Enzymes

Answer 27

Lower the activation energy required for a chemical reaction to occur

Question 28

In type 2 diabetes mellitus, which component(s) of the insulin feedback loop is/are first disrupted?

Answer 28

The effector

Question 29

Ribosomes are most closely associated with

Answer 29

mRNA translation
Protein synthesis

Question 30

From rest, if we allow only potassium to cross a cell’s membrane, the cell would get

Answer 30

More negative

Question 31

Where does gene transcription occur in a cell?

Answer 31

The nucleus

Question 32

Ions moving down their electrochemical gradient

Answer 32

Release potential energy

Question 33

When blood glucose climbs, an effector that helps the body return to homeostasis is located in the

Answer 33

Skeletal muscle

Question 34

Glucose does not simply diffuse through a cell’s plasma membrane because

Answer 34

Glucose is polar, but a cell’s plasma membrane is not

Question 35

In resting human cells, an electrical gradient pushes potassium

Answer 35

Into a cell

Question 36

Translation is the name for a process in which

Answer 36

An RNA template is used to assemble proteins from amino acids

Question 37

The production of a protein from mRNA is called

Answer 37

Translation

Question 38

A gene provides instructions for the

Answer 38

The primary structure of the protein

Question 39

Osmosis refers to

Answer 39

The diffusion of water

Question 40

Do humans maintain blood glucose homeostasis?

Answer 40

Yes