Transport Across Membrane Flashcards
(13 cards)
Tell about barrier
Selectively permeable barrier
Between cytoplasm and the exterior of the cells that means plasma membrane.
What is plasma membrane do
Both phospholipid bilayer and integral proteins control movement of substances across the membrane in both ways
So what is the important of plasma membrane
Membrane maintain constant internal environments
Tell about passive diffusion
1basic structural unit of the bio membrane is the lipid bilayer.
2lipid soluble substances diffuse through it to the other side
3 chemical concentration graient
4no ATP
5 rate depend on concentration gradient and substances hydrophobicity
6 it may operate in both direction
7little selectivity
Passive diffusion under go substances
Gases
Small hydrophobic molecules
Small uncharged polar molecules
Bilayer is slightly permeable to urea and water
Passive diffusion doesn’t transport
Ions
Larged uncharged polar molecules-glucose
Charged polar molecules-amino acid ATP
These substances are water soluble thats why they doesnot undergo passive diffusion
What are membrane transport proteins
ATP powered pumps
Channel proteins
Transporters
Membrane transport proteins what do they do
Certain integral proteins move substances across the membrane
Why lipid solubility is not necessary for substances when they undergo through membrane transport proteins?
Due to substances does not touch bilayer.
ATP powered pumps
Form of active transport
With 2 points
What are 4 types of ATP powered pumps
P class
F class
V class
ABC class
Channel protein
No ATP
Water and specific ions move
Uniport
Both direction
Facilitated diffusion doesnot change the substances chemically
