BIO 201 Exam 2 (Frampton, UNCW) Questions & Answers With Complete Solutions Graded A+

BIO 201 Exam 2 (Frampton, UNCW)
Questions & Answers With Complete
Solutions Graded A+
QUESTIONS AND ANSWERS

Amphipathic Macromolecules. ANSWER -Both hydrophilic and hyrdrophobic




Examples of Amphipathic Macromolecules. ANSWER -1. Phospholipids

2. Proteins in a membrane




Membrane Characteristics. ANSWER -A. Membranes form spontaneously

B. Membrane structure is tightly controlled by cells.

We call the resulting structure a fluid mosaic.

1. 2 semifluid leaflets of lipids

2. 2 classes of proteins with numerous functions

3. Carbohydrates face the outside of the cell

C. Membrane "mosaic" structure enables

membrane function, and membrane have a

lot of functions to perform!




Hydrophobic Interactions. ANSWER -cage-like structure of water

, forms around hydrophobe




Step 1 of membrane fluidity. ANSWER -Step 1. Hydrophobic exclusion pushes fatty
acids tails of phospholipids together




Step 2 of membrane fluidity. ANSWER -H-bonds and

hydration spheres form

between water & the

hydrophilic heads.




Step 3 of membrane fluidity. ANSWER -van der Waals

interactions among the

hydrophobic portions of

molecules determines

membrane fluidity.




Relationship between fluidity and Van der Waals forces. ANSWER -More van der
Waals

equals less fluidity.




Leaflet. ANSWER -one half

(layer) of the