Membranes can keep certain molecules inside and out of the cell. What is this function called
Selective Barrier
100
What organelles use membranes to form "compartments"
Nucleus, chloroplast, mitochondria
100
What are the different things that can affect fluidity?
Saturation, length of tails, cholesterol, temperature
200
There are three "other" functions of the membrane name two of them.
Receiving Information, Capacity for movement and expansion, import and export of small molecules
200
What makes up a phospholipid? Draw a cartoon diagram and label the parts
Phosphate hydrophilic head and two hydrophobic fatty acid tails
200
What does a saturated fatty acid look like. How does saturation affect fluidity
Straight tail. The more unsaturated fatty acids make a more fluid membrane
300
If a lipid has a sugar attached to its head, what is it called and is it hydrophobic or hydrophilic
Glycolipid and hydrophilic
300
Which is more likely to have longer fatty acid tails: An arctic fish or a fish that lives in a hot springs
The hot springs fish because the increased heat makes a more fluid membrane, it needs to counteract with long tails that cause a less fluid membrane
400
If a membrane was broken what would happen: a) it will stay broken b) it will reform c) not enough information. Please explain your reasoning
The membrane will reform because of its amphipathic nature. The hydrophilic heads will face the water, while the hydrophobic tails want to avoid the water.
400
Why is the bilayer called asymmetrical?
Some phospholipids are only on one side. Glycolipids are only on the extracellular side. There is an unevenness between the membranes therefore it is assymmetrical
400
What is the purpose of cholesterol in membrane bilayers
It serves as a wedge between membrane lipids and typically decreases fluidity.
500
What are the 4 ways a membrane can move or diffuse. Which one occurs the least often
Lateral, flexion, rotation, flip-flop is the rarest