Melanocyte-Stimulating Hormones Are

question 217

Multiple Choice

Melanocyte-stimulating hormones are

• A) secreted by the intermediate lobe of the pituitary in some lower vertebrates.
• B) known to cause skin darkening in certain lower vertebrates.
• C) believed to be responsible for the tanning phenomenon in humans.
• D) both (a) and (b) above.
• E) all of these answers.

---

Definitions:

Meiosis

Process in which a 2n cell undergoes two successive nuclear divisions (meiosis I and meiosis II), potentially producing four n nuclei; leads to the formation of gametes in animals and spores in plants.

Prophase II

The first stage of meiosis II, where the genetic material condenses into visible chromosomes, preparing for eventual separation into daughter cells.

Metaphase I

A stage of meiosis where homologous chromosomes pair up and align along the equatorial plate of the cell.

Prophase I

The first stage of meiosis I, where chromosomes condense, pair up, and exchange genetic material via crossing over.