Chapter 2: Overview of Cellular Physiology

Chapter 2. Overview of Cellular Physiology

The electrogenic Na, K ATPase plays a critical role in cellular physiology by

A. using the energy in ATP to extrude 3 Na⁺ out of the cell in exchange for taking two K⁺ into the cell.

B. using the energy in ATP to extrude 3 K⁺ out of the cell in exchange for taking two Na⁺ into the cell.

C. using the energy in moving Na⁺ into the cell or K⁺ outside the cell to make ATP.

D. using the energy in moving Na⁺ outside of the cell or K⁺ inside the cell to make ATP.

Cell membranes

A. contain relatively few protein molecules.

B. contain many carbohydrate molecules.

C. are freely permeable to electrolytes but not to proteins.

D. have variable protein and lipid contents depending on their location in the cell.

E. have a stable composition throughout the life of the cell.

Second messengers

A. are substances that interact with first messengers outside cells.

B. are substances that bind to first messengers in the cell membrane.

C. are hormones secreted by cells in response to stimulation by another hormone.

D. mediate the intracellular responses to many different hormones and neurotransmitters.

E. are not formed in the brain.

The Golgi complex

A. is an organelle that participates in the breakdown of proteins and lipids.

B. is an organelle that participates in posttranslational processing of proteins.

C. is an organelle that participates in energy production.

D. is an organelle that participates in transcription and translation.

E. is a subcellular compartment that stores proteins for trafficking to the nucleus.

Endocytosis

A. includes phagocytosis and pinocytosis, but not clathrin-mediated or caveolae-dependent uptake of extracellular contents.

B. refers to the merging of an intracellular vesicle with the plasma membrane to deliver intracellular contents to the extracellular milieu.