The movement of molecules down a concentration gradient through transport proteins in the cell membrane is a type of

In cells, somemolecules can movedown theirconcentration gradients by crossing the lipid portion of the membrane directly, while others must pass through membrane proteins in a process called facilitated diffusion.

Explanation:

please mark as brainlist answers

the sphincter muscles at the end of the digestive tract is the anus.

homeostasis is the tendency towards a relatively stable equilibrium between interdependent elements, especially as maintained by physiological processes. and this is how it applies to the integumentary system. back to top. skin functions in homeostasis include protection, regulation of body temperature, sensory reception, water balance, synthesis of vitamins and hormones, and absorption of materials. when body temperature falls, the sweat glands constrict and sweat production decreases.