Proteins in the cell membrane Flashcards
Two groups of proteins:
integral proteins (intrinsic) and peripheral proteins (extrinsic)
Integral proteins can be found in…
the inner, outer layer or spanning the whole membrane. (transmembrane proteins)
Some of the integral proteins are…
fixed.
Peripheral proteins are found…
on the inner or outer surface of the membrane.
Transport proteins form…
hydrophilic channels or passageways for ions and polar molecules to pass through the membrane.
Types of transport proteins:
- channel proteins
- carrier proteins
Glycoprotein or glycolipid has…
short branching chain of carbs attached to the protein or lipid.
Carb chains are attached to…
the side of a molecule which faces outside.
Glycoproteins and glycolipids functions:
- the chains project into water fluids where they form hydrogen bonds, which stabilises the membrane
- can form a sugary coating =glycocalyx
- antigens
Channel proteins are water-
filled pores.
Channel proteins allow charged…
substances to diffuse.
Most of the channel proteins are
gated. Part of the protein molecule on the inside surface of the membrane can move to close or open the pore.
Some of the channels occur in…
a single protein, other can be formed by several proteins.
Channel proteins have fixed…
shapes.
Carrier proteins can flip…
between two shapes.
