4.1 Cell Membrane Flashcards
What is cholesterol found within?
Phospholipid bilayer And are very hydrophobic
Cholesterol is a significant component of cell membranes, contributing to their structure and fluidity.
What affect does hydrophobia have on cholesterol
This hydrophobic nature allows cholesterol to integrate well within the lipid bilayer.
What are the functions of cholesterol in the cell membrane?
Cholesterol stabilizes the membrane by restricting the movement of phospholipids and other molecules.
Also prevents water leakage and dissolved ions escaping from the cell
What are glycoplipids made up of?
A carbohydrate covalently bonded to a lipid
The carbohydrate portion extends from the bilayer to the aqueous environment outside the cell.
What are the functions of glycoplipids? (List at least two)
- Act as recognition sites
- Help maintain membrane stability
- Help cells to attach together to form tissues
Glycolipids play essential roles in cell recognition and adhesion.
What are glycoproteins?
Proteins attached to carbohydrate chains on the outer surface of the cell membrane are glycoproteins.
Glycoproteins serve crucial roles in cellular communication and interaction.
What functions do glycoproteins perform? (List at least two)
- Act as recognition sites
- Help cells form tissues
- Allow cells to recognize each other
They are essential for immune response and tissue formation.
True or False: Glycolipids help cells to recognize each other.
True
This recognition is crucial for cellular communication and tissue formation.
Fill in the blank: Glycoproteins act as cell-surface receptors for _______ and neurotransmitters.
[hormones]
Glycoproteins play a key role in signal transduction by binding to hormones.
What is the structure of a phospholipid
A phospholipid consist of a hydrophilic head pointing to the outside of the cell membrane and a hydrophobic tail pointing inwards to the centre of the cell membrane
What is the function of a phospholipid?
Phospholipids form the phospholipid bilayer which allows lipid soluble substances to enter and leave the cell.
Prevents water soluble substances from entering the cell.
Makes the membrane flexible.
What molecules can travel across the cell surface membrane and how?
~Lipid soluble molecules as they can pass through the bilayer
~non polar molecules as they can travel against the non polar hydrophobic tails on the bilayer
~small molecules as they can pass through the channels in the membranes
~molecules of the opposite charge as they wont repel
Where is a protein found and what are the 2 types?
Found in the phospholipid bilayer - they’re either extrinsic or intrinsic.
Extrinsic proteins provide mechanical support towards the membrane.
Where is a protein found and what are the 2 types?
Found in the phospholipid bilayer - they’re either extrinsic or intrinsic.
Extrinsic proteins provide mechanical support towards the membrane.
What are the functions of proteins in the membrane
~ act as channels to transport, water, soluble molecules across the membrane
~ help sells adhere together
~ act as receptors and also provide structural support to the membrane
~ allow active transport through a carrier proteins
