tempratures and membranes Flashcards
how does temperature affect membranes ?
it affects how much the phospholipids in the bilayer can move, which affects membrane structure and permeability.
what happens when tempratures reach below 0 C in the cell membranes ?
The phospholipids don’t have much energy, so they can’t move very much.They’re packed closely together and the membrane is rigid. But channel proteins and carrier proteins in the membrane denature (lose structure and function), increasing the permeability of the membrane . Ice crystals may form and pierce the membrane, making it highly permeable when it thaws.
what happens to the cell membrane between temps of 0 C and 45 C ?
The phospholipids can move around and aren’t packed as tightly together — the membrane is partially permeable .As the temperature increases the phospholipids move more because they have more energy — this increases the permeability of the membrane.
what happens to the cell membrane in temps above 45 c ?
The phospholipid bilayer starts to melt (break down) and the membrane becomes more permeable.
Water inside the cell expands, putting pressure on the membrane.
Channel proteins and carrier proteins in the membrane denature so they can’t control what enters or leaves the cell — this increases the permeability of the membrane .
