Use This Description to Answer the Following Question

question 49

Multiple Choice

Use this description to answer the following question.
A major group of G-protein-coupled receptors contains seven transmembrane α helices. The amino end of the protein lies at the exterior of the plasma membrane. Loops of amino acids connect the helices either at the exterior face or on the cytosol face of the membrane. The loop on the cytosol side between helices 5 and 6 is usually substantially longer than the others.
-Which of the following processes includes all the others?

• A) osmosis
• B) diffusion of a solute across a membrane
• C) facilitated diffusion
• D) passive transport
• E) transport of an ion down its electrochemical gradient

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Definitions:

Ova

The female reproductive cells, or eggs, which are capable of developing into a new organism when fertilized by a sperm cell.

Oocytes

Immature eggs found in the ovaries of females that, upon maturation, can undergo ovulation and potentially fertilization.

Endometrium

The mucous membrane lining the interior of the uterus, which thickens during the menstrual cycle in preparation for possible implantation of an embryo.

Blastocyst

An early stage of embryonic development, a structure formed in the early development of mammals, consisting of a sphere of cells surrounding an inner fluid-filled cavity.