Active transport

importance of active transport in the uptake of glucose by epithelial cells of kidney tubules

kidney reabsorbs useful substanes such as glucose from the blood during filtration.

-glucose is transported from the kidney tubules into the epithelial cells of the capillaries against concentration gradient.

importance of active transport in the uptake of glucose by epithelial cells of villi and kidney tubules

• glucose is absorbed from the epithelial cells of the villi in the small intestine and transported to the body cells and tissues through the bloodstream.

• cells may need glucose which is already in higher concentration in the cell compared to the outside surrounding.

• hence, glucose moves against concentration gradient by active transport.

• energy released during respiration and is used by carrier proteins in the cell membrane to absorb the glucose against concentration gradient.

importance of active transport in uptake of mineral ions by root hairs

-mineral ions like phosphate and nitrates are absorbed by root hair cell from the soil through active transport.

-these ions are often in higher concentration in the root hair cell than in the soil, hence cannot easily diffuse across.

-the nutrients are absorbed from a low concentration in the soil agianst the concentration gradient.

-active transport requires energy in form of ATP which is used by carrier proteins in the cell membrane to take the ions from a low concentration.

active transport

the movement of particles [ions /molecules] through the cell membrane from the region of low concentration to a region of higher concentration against concentration gradient, using energy from respiration