2. Which of the following statements about biological membranes are true? (Select all that apply.) a. Hydrophobic tails of phospholipids face toward each other; hydrophilic heads face out. b. Phospholipids can move laterally in their half of the bilayer. c. The carbohydrate group attached to membrane glycoproteins faces the cytosol. d. They are selectively permeable.

2. Which of the following statements about biological membranes are true? (Select all that apply.) a. Hydrophobic tails of phospholipids face toward each other; hydrophilic heads face out. b. Phospholipids can move laterally in their half of the bilayer. c. The carbohydrate group attached to membrane glycoproteins faces the cytosol. d. They are selectively permeable.

Concepts of Biology

1st Edition

ISBN:9781938168116

Author:Samantha Fowler, Rebecca Roush, James Wise

Publisher:Samantha Fowler, Rebecca Roush, James Wise

Chapter3: Cell Structure And Function

Section: Chapter Questions

Problem 11RQ: The tails of the phospholipids of the plasma membrane are composed of _____ and are _____? a....

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1. Passive transport of molecules is determined by the concentrations gradient of such molecules A. True B. False 2. Plasmalemma is the same as the plasma membrane A. True B. False 3. Phospholipids are always oriented so that their polar head faces the calcium ions A. True B. False 4. Which of these is not a function of the lipid bilayer? A. Changes the temperature B. Provides a flexible matrix C. Imposes a barrier to permeability 5. Which of these is not true about enzymes? A. Most of them are proteins B. Are changed at the end of the reaction C. Can only speed up the rate of the reaction D. Very specific in function E. Work better in specific medium
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