Which molecules dramatically increases the rate of diffusion of water across cell membranes?

AQUAPORINS dramatically increases the rate of diffusion of water across cell membranes.

Explanation:

Aquaporins are integral membrane proteins also called water channels that forms pores in the membrane mainly for facilitating diffusion of water molecules in and out of the cell. Aquaporins selectively allow the passage of water molecules while preventing the passage of ions and other solutes through it as they are impermeable to protons, and large solutes. These proteins therefore increases the permeability of the membrane to water molecules and the rate of diffusion of water increases through them. Flow of water molecules in aquaporins follows the direction of osmotic pressure across the membrane. Aquaporins in some organisms have been modified to voltage gated aquaporins which helps them to close the water channels in unfavorable conditions such as drought and flooding. This is to prevent excessive loss of water to the surrounding or intake of water into the cells.

answer: the exterior temperature of commercial jet planes as they leave the stratosphere and return to the ground increases steadily.

explanation:

the lower most layer of atmosphere is troposphere which extends from 0 to 12 km above the surface of the earth. the temperature initially decreases as distance is increased from the earth's surface. commercial jets fly in lower part of the stratosphere. the stratosphere extends upto 50 km. the temperature in stratosphere starts rising again due to presence of ozone which traps the uv rays.

thus, when the planes leave the stratosphere and return to the ground, the exterior temperature increases steadily.

see earlier