Exam 5: Membrane Transport and Cell Signaling

Several species of bacteria and archaea live in hot springs and deep sea thermal vents where the water temperature exceeds 90°C (194°F).Which of the following evolutionary adaptations would you expect to find in the cell membranes of these thermophilic organisms?

Signal transduction pathways that include a phosphorylation cascade

The primary function of G proteins in signal transduction is

Binding of the signaling molecule epinephrine to its receptor results in

Immediately following binding of a growth factor,an activated receptor would most likely stimulate

Phosphorylation cascades involving a series of protein kinases are useful for cellular signal transduction because

The primary structural components of the cell membrane are

Following activation of a receptor,which sequence below represents the correct order in which components will be involved in a signaling pathway that utilizes the second messenger cAMP?

Which of the following factors would tend to increase membrane fluidity?

How is the plant hormone ethylene delivered to target cells?

Why are lipids and proteins free to move laterally in membranes?

Which of the following is required for the sodium-potassium pump to transport potassium ions into an animal cell?

Which of the following statements about diffusion is correct?

Submerging a red blood cell in a hypertonic solution will result in

Which of the following is most likely true of a protein that cotransports glucose and sodium ions into the intestinal cells of an animal?

At puberty,an adolescent female body changes in both structure and function of several organ systems,primarily under the influence of changing concentrations of estrogens and other steroid hormones.How can one hormone,such as estrogen,mediate so many effects?

Based on the fluid mosaic model of cell membranes,which of the following statements about membrane phospholipids is true?

Which of the following is a primary function of an electrogenic pump in cell membranes,such as the sodium-potassium pump?

A proper relationship between an enzyme and its function is illustrated by which of the following?

The sodium-potassium pump generates the following concentration gradients across the plasma membrane: