Question

1. Which of the following processes requires energy input?

a. Active Transport

b. Facilitated Diffusion

c. Both Simple Diffusion and Facillitated Diffusion

d. Simple Diffusion

e. Osmosis

f. Both Active Transport and Facillitated Diffusion

2. Which of these processes require a protein in the membrane for it to occur?

a. Both facillitated diffusion and active transport require a protein in the membrane

b. Only active transport requires a protein in the membrane

c. Both osmosis and diffusion require a protein in the membrane

d. Only osmosis requires a protein in the membrane

e. Only facillitated diffusion requires a protein in the membrane

3. At home I keep my honey jar at room temperature because almost nothing can grow and contaminate the honey. Which of the following best describes why microbes can't grow in honey?

a. Honey is very hypertonic

b. Honey crosses the cell membrane through diffusion

c. Honey is very hypotonic

d. Honey requires facillitated diffusion to cross the membrane

e. Honey crosses the membrane through a protein channel

4. The glucose transporter used by cells to obtain glucose from the media is a protein embedded in the membrane. When researchers first started to investigate the glucose transporter's structure they had trouble because it seemed to have 2 differnet shapes! Eventually they realized that the glucose transporter changes shape as it moves glucose into the cell but does not require energy to do it's work. Which of the following is the best description for the glucose transporter?

a. It's a carrier protein doing facillitated diffusion

b. It's a carrier protein doing active transport

c. It's a protein channel doing facillitated diffusion

d. It's a protein channel doing active transport

Answer 1

1) active transport requires the energy of ATP to transport molecules from low concentration to high concentration,

facilitated diffusion, osmosis, and simple diffusion does not require the energy input so the answer is a) active transport.

( facilitated diffusion is the transport of molecules from high concentration to low concentration down the concentration gradient without the input of energy, simple diffusion is the movement of molecules from high concentration to lower concentration, osmosis is the movement of water molecules from high concentration to lower concentration)

2) facilitated diffusion is the transport of molecules from high concentration to low concentration down the concentration gradient without the input of energy, by a membrane protein, active transport is the transport of molecules from low concentration to high concentration, against the concentration gradient by a membrane protein, so the answer is

a. Both facilitated diffusion and active transport require a protein in the membrane

(simple diffusion is the movement of molecules from high concentration to lower concentration, osmosis is the movement of water molecules from high concentration to lower concentration)

3) a solution is hypertonic compared to another, when the concentration of solutes in that is greater than the other,

a solution is hypotonic compared to another, when the concentration of solutes in that is lower that the other.

a solution is isotonic to another solution when the concentration of solutes ib both are same.

bacteria or microbes cannot grow in a hypertonic solution, the concentration of water is low in a hypertonic solution, osmosis is the movement of water from higher concentration to lower concentration, so if bacteria is placed in a hypertonic solution, water moves out of bacteria and it dies.

honey has higher concentration of solutes so water moves out of bacteria in the honey and it dies, so the answer is a. Honey is very hypertonic

4) this process does not require energy and requires a membrane protein so the answer is a. It's a carrier protein doing facilitated diffusion

( facilitated diffusion is the transport of molecules from high concentration to low concentration down the concentration gradient without the input of energy, active transport is the transport of molecules from low concentration to high concentration, against the concentration gradient by a membrane protein)