Lecture Three Flashcards
Cells need to do these 5 things.
Obtain raw materials, remove waste, generate energy, manufacture cellular materials, control all of these functions
Why do cells require a cell membrane?
So that the cell has separate, special conditions compared to its outside.
What is the name of the membrane at the boundary of each cell?
Plasma membrane
What is the plasma membrane made of?
A phospholipid bilayer, which is made of a hydrophilic phosphate head and 2 hydrophobic fatty acid tails
What does it mean if a fat is fully saturated?
No double bonds, which means that it will solidify when at room temperature
What does it mean if a fat is unsaturated?
It contains a double bond, which means that the structure has kinks in it. This makes it fluid at room temperature.
What molecule stabilises the plasma membrane’s fluidity? What molecule group is it?
Cholesterol, lipid
What are the five main functions of proteins?
Signal transduction, cell recognition, intercellular recognition, linking cytoskeleton and extracellular matrix, membrane transport
This is a protein function, and relays messages from the body (or environment) into the cell.
Signal transduction
This is the combination of glucose and a protein.
Glycoprotein
The movement of substances across membranes depends on what three factors?
The type of molecule, size, and how many of the molecule
What are the two categories of molecule transport across membranes?
Passive and active
If I was going to a party with very few people in it, and the door was wide open and I walked in, this would be similar to what form of transport across membranes?
Diffusion
If I was going to a party, and a bouncer was outside and let me in, this would be most similar to what form of transport across membranes?
Facilitated diffusion
If I was going to a party, and there was a bouncer outside whom I had to pay $10 to get in, this would be most similar to what form of transport across membranes?
Active transport
If I was going to a party, and there was bouncer, and I had a celeb friend, and they paid $10 to get in, which kicks one celeb out, this would be most similar to what form of transport across membranes?
Co-transport
Why do organelles need a plasma membrane?
To keep processes separate, and to keep special conditions for each process. Also creates concentration gradients and allows package of substances for export and transport.
All cells have these 4 things.
Plasma membrane, cytosol, ribosomes, chromosomes
This type of protein fully penetrates the phospholipid bilayer
Integral protein
This type of protein only partially penetrates the phospholipid bilayer.
Transmembrane protein
What are the two main roles of membrane carbohydrates in cell-to-cell recognition?
Sorting and recognition by binding
What is the inside of the plasma membrane called?
Intracellular
What is the outside of the plasma membrane called?
Extracellular
What type of molecule is the easiest to dissolve into the plasma membrane/go through cell wall?
Non-polar molecules
