Which of the following statements about hormones initiating second messenger systems is (are) true?

a) A lipophilic hormone initiates the system by binding to a receptor on the cell membrane
b) A single hormone molecule binding to a receptor can ultimately activate millions of proteins
c) A G protein is considered to be the second messenger
d) Both a and b are true
e) Both b and c are true


Answer: b) A single hormone molecule binding to a receptor can ultimately activate millions of proteins

Biology & Microbiology

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Biology & Microbiology

Fats are major constituents of

a. proteins. b. genes. c. photosynthesis. d. cell membranes. e. all of these.

Biology & Microbiology

The species concept defined as a group of organisms that are capable of interbreeding to produce fertile offspring is ________

A) the morphospecies concept B) the phylogenetic species concept C) the biological species concept D) the ecological species concept

Biology & Microbiology

If an organism is eukaryotic, then by definition it will:a

be assigned to the domain Bacteria. b. be assigned to the domain Archaea. c. be unicellular. d. possess gametangia. e. possess a nucleus

Biology & Microbiology