Transport Flashcards
1
Q
briefly describe the process of co transport of a glucose molecule
A
- the sodium ions are actively transported out of the epithelial cells into the blood
- this maintains a much higher concentration of sodium ions in the lumen
- sodium ions then diffuse into the epithelial cells down the concentration gradient
- the glucose pass into the blood plasma via facilitated diffusion
2
Q
what is simple diffusion
A
the net movement of molecules from high to low concentration
3
Q
why is facilitated diffusion considered a passive process
A
because it relies on the kinetic energy of the diffusing molecules
4
Q
contrast simple and facilitated diffusion
A
- simple can diffuse non polar like oxygen
- faciliated diffuses charged and polar molecules
5
Q
what 2 things are involved with the facilitating of diffusion
A
- carrier proteins
- protein channels
6
Q
why is facillitated diffusion neccesary
A
charged ions and polar molecules cant diffuse because of their hydrophobic nature and phospholipid tails