PLANTBI C112 Quiz: 33 Microbial Evolution

Describe evidence that supports the hypothesis that cell membranes are fluid.

In what ways are cell membranes more than simple lipid bilayers?

How does the saturation state of the hydrocarbon tail groups influence membrane fluidity?

How and why does cholesterol alter the fluidity of a membrane?

Describe evidence that supports the hypothesis that cell membranes are fluid. In what ways can membrane proteins move freely in cell membranes? How are they constrained?

(Please answer all subparts of the question, thanks so much.)

The inner membranes of cyanobacteria are very similar to those of the thylakoid membrane of chloroplasts. This similarity supports the hypothesis that chloroplasts evolved from symbiotic cyanobacteria. Which other organelles may have originated in the same way? Explain, providing evidence for your choice.