Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

The hydrophilic heads of the phospholipids in the plasma membrane face a water-b

ID: 96187 • Letter: T

Question

The hydrophilic heads of the phospholipids in the plasma membrane face a water-based environment Integral proteins always extend completely through the plasma membrane Endergonic reactions can sometimes release energy Enzymes themselves are altered in the process of catalyzing chemical reactions A cell can use energy released during exergonic reactions to drive endergonic reactions A single molecule is always either hydrophobic or hydrophilic and can never possess (at the same time) a region that is hydrophobic and a region that is hydrophilic Passive transport of a molecule across a lipid bilayer only occurs if there is a significant difference in the concentration of that molecule from one side of the bilayer to the other Transport proteins are integral plasma membrane proteins Osmosis is an example of passive transport A cell wall stops a plant cell from taking in too much water so that it won't burst

Explanation / Answer

26) Phospholipids are arranged as bilayers in cell membrane. They consist of hydrophilic heads and hydrophobic tails. The polar region or the hydrophilic heads face outwards and interact with the water molecules. The hydrophobic non-polar tails face inward. Therefore, the given statement is true.

27) Integral proteins need not be extended completely through the plasma membrane. So, the given statement is false.

28) Endergonic reactions require energy. Therefore, the given statement is false.

29) Enzymes themselves are not altered during the course of a catalytic reaction. Therefore, the statement is false.

30) True

31) False

32) True

33) True

34) True

35) True