Cell Membrane Structure (Phospholipid Bilayer)
What is the primary macromolecule that makes up the cell membrane
Phospholipids
What type of transport moves substances from high concentration to low concentration without using energy?
Passive transport
what is active transport?
movement across the membrane from low concentration to high concentration.
What is homeostasis
The maintenance of stable internal conditions within an organism.
In the phospholipid bilayer, which part is hydrophilic.
the heads.
In diffusion, particles move from areas of ______ concentration to ______ concentration.
high to low.
what type of energy is used to help move molecules across the cell membrane?
ATP.
What type of transport moves substances across the cell membrane without using ATP?
Passive transport.
In the phospholipid bilayer which part is hydrophobic
the tails.
Osmosis is the movement of what?
Water
A structure in the cell membrane that changes shape to carry small molecules in and out of the cell.
A protein pump.
What is the main difference between negative and positive feedback in homeostasis?
Negative slows down and positive speeds up.
the type of membrane transport that uses embedded proteins to move large or charged molecules across the bilayer.
Facilitated diffusion
Facilitated diffusion uses ______ proteins.
channel or carrier.
Large molecules are transported into the cell by this type of active transport.
Endocytosis
If a cell is placed in a hypertonic solution, what will happen to its water balance?
it will shrink
what helps regulate membrane fluidity
cholesterol
If a plant cell is placed in pure water what happens to it due to osmosis?
it swells.
The sodium/potassium pump transports ________ out of the cell and __________ into the cell.
Na⁺, K⁺.
What is the structure of the cell membrane that allows it to be semi-permeable?
The phospholipid bilayer.