2.4.5 Active Transport Flashcards
What is active transport
The movement of particles through a cell membrane from a region of lower concentration to a region of higher concentration using energy from respiration
Why is energy needed
Energy is needed because particles are being moved against a concentration gradient, in the opposite direction from which they would naturally move (by diffusion)
Active transport across the cell membrane involves, what?
involves protein carrier molecules embedded in the cell membrane
Food molecules (such as the sugar glucose) can be absorbed across the wall of the small intestine by diffusion, but this is dependent on what?
on a concentration gradient existing between the lumen of the intestine and the bloodstream
Active transport allows molecules such as glucose to be transported into where?
to be transported into the bloodstream from the lumen of the small intestine (the gut) when the concentration of sugar molecules in the blood is higher
The active uptake of glucose by epithelial cells in kidney tubules in the kidney nephron allows for what?
the reabsorption of glucose back into the blood so that none is lost in the urine
Sugar molecules are used in respiration to do what?
to release energy for cells to function
Root hair cells lining the surface of plant roots need to move minerals such as magnesium ions to where?
from a region of lower concentration (the very dilute solution of minerals in the soil surrounding the roots) to a region of higher concentration (inside the cytoplasm of the cell)
Are mineral ions needed by plants?
Mineral ions are needed by plants to function
In plants, what are Magnesium ions required for?
are required to make chlorophyll
Nitrate ions are needed to make what?
Nitrate ions are needed to make amino acids for protein synthesis (and subsequently growth)
