Transport Flashcards
Roles of membrane transport
Regulate intracellular ph
Regulate cell volume
Generation of ionic gradient
Mantaining ionic composition
Nutrient uptake and removing waste
Plasma membrane works as a
Lipid and lipid soluble substances
Barrier to water (may diffuse very slowly)and water soluble substances
Can pass through
Types of membrane transport
1 ion channels
2 carrier proteins
Ion channels have
What can pas through
Watery spaces all the way through them that composed of hydrophilic amino acids
Water and specific ions may be molecules too
(Agar ionaka ch bargayak bu awa ion channel rek 3aksi aw)
Carrier proteins
They bind to the molecules or ions and undergo conformational changes opening a pore through them
Types pof membrane transport
1 passive membrane transport
2 active membrane transport
Passive membrane transport
Moving substances through the bilayer or ion channels with out using energy down their concentration or electrical gradient
Types
Simple diffusion —-through lipid bilayer
I___through protein layer
Facilitated Carrier mediated diffusion
Osmosis
Two types of gradient
Concentration gradient
Electrical gradient more positively charged ions in on side than the other
A opposites attract negative ions move toward possitive concentration
B equal charged distribution
equilibrium
the equal distribution of charge and/or concentration of a molecule
Active transport
Moving molecules against their concentration or electrical gradient using energy
-Primary active transport
-Secondary active transport
Two types of channels
Tow types of ion channels
1 ion channels
1 Leaky ion channels they are always open
2 gated ion channels
2 water channels ( aquaporins)
Charactersic of protein channels is
What makes it
Selective permeability
Shhape diameter and nature of electrical charges along the inside surface
Gated ion channles
Voltage gated ion channels
They will open when theres a change in electrical potential
Ligand gated ion channels
When they bind to the specific ligand they undergo conformational change or chemical bonding chnge that closes or opens the gate
Gap junctions ; intercellular channels factors like PH and presence of Ca regulate comunication between the cells
Glucose and amino acids are transported by
Facillitated or carrier mediated diffusion
Osmosis
Spontanous diffusion of water or other solvents through the smipermeable membrane
Osmolarity
The concentration of solutes in a solution
Prmary active transport
Uses enegry directly ( the energy thats liberated frm ATP)
Uses energy indirectly energy is derived from the energy that has been stored in form of concentrtion gradient
With out Na K pump cells will
Burst
Glucose movement
Alway by facilated diffusion only in intestine and kidney tubule by sadium co transport
Sodium counter transport
1 na ca exchanger ( in all of the cells)
2 na h counter transport ( in renal tubule)
