A computer model is a _______

(a) Identify the most likely mode of transport across the membrane for substance L. Explain how information provided helps deter

Viefleur [7K]

Active transport occurs against the electrochemical gradient. It needs energy to move molecules from the lower concentration side to the higher concentration side. The mode of transport is active transport. 

-------------------------------------------------

There are three main different types of transport across the membrane

Simple diffusion ⇒ Does not need energy to occur
Facilitated transport ⇒ Does not need energy to occur
Active transport ⇒ Needs energy to occur

Active transport is the transport of molecules that move against the electrochemical gradient, so it does need energy to happen.

Molecules move from the lower concentration side to the higher concentration side of the membrane.

Carrier proteins are in charge of active transport. The needed energy might proceed from the ATP molecules or the membrane's electric potential.

In the exposed example, a scientist wants to determine how substance L enters a cells in a culture.

The cells maintain a 120 mM intracellular concentration of substance L.

Varying external concentrations of substance L (10 to 100 mM) in culture medium (Table 1).

Table 1. Rate of entry of substance L into mammalian cells in culture

External concentration of substance(mM) Rate of entry of substance L

10 5%

20 25%

30 45%

40 65%

50 80%

60 90%

70 95%

80 100%

90 100%

100 100%

Now, we need to identify the most likely mode of transport across the membrane for substance L, and explain how information provided helps determine the most likely mode of transport.

We know that the intracellular concentration is 120mM.

As we can see, this concentration exceeds all of the culture media concentrations. Yet, the substance keep moving into the cell.

As the concentration inside the cell is always higher than the concentration outside, we can assume that this is not passive transport because the molecule transport is going against its concentration gradient.

Hence, the remaining option is active transport. And as said before, we can see it because the substance keeps crossing the membrane toward the cell interior despite its concentration being higher in the interior of the cell than in the exterior.

-------------------------------------------------------------

6 0

3 years ago

How does the stigma help the sticky monkeyflower reproduce?

scoundrel [369]

Stigma is complex for its blend substances. For example, it can trap pollen and prepare pollen grains for fertilization. hope I helped shawty :)

5 0

3 years ago

A researcher collected a single-celled organism from birdbath water and grew the organism in a laboratory. The researcher observ

ser-zykov [4K]

Answer: The organisms exhibit a form of Asexual reproduction.

Explanation:

This is a form of asexual reproduction because Asexual reproduction is a form of reproduction where a single celled organisms or muiticellular organisms produce or divide to produce offsprings that are genetically identical without fusion of gametes and exchange of genetic materials.

This type of reproduction includes binary fission( where an organism divides into two), fragmentation( where an organism divides into fragments), budding, spore formation e.t.c.

8 0

3 years ago

As latitude increases, density.............?

Digiron [165]

The density decreases because you are coming closer to the atmosphere and away from the center of the earth

6 0

3 years ago

PLEASE HELP FAST WILL GIVE BRAINLIEST

garik1379 [7]

Answer: True

Explanation:

8 0