CFP Fish Biology & Physiology 3

Question 1

What term describes the bright or distinctive colors many fish develop during spawning season to attract mates?

Accepted Answer

Nuptial coloration

Answer

Nuptial coloration refers to the striking breeding colors (typically in males) that appear during spawning season to attract mates and signal reproductive fitness, as seen in male brook trout and sockeye salmon.

Question 2

Which hormone class plays the primary role in triggering smoltification in juvenile Pacific salmon?

Accepted Answer

Thyroid hormones (thyroxine)

Answer

Thyroid hormones, particularly thyroxine (T4), are the primary drivers of smoltification, stimulating the broad physiological changes in gill ion-transport capacity, body morphology, and migratory behavior needed for seawater life.

Question 3

What is the migratory life history pattern of catadromous fish such as American eels?

Accepted Answer

Born in the ocean, migrate to freshwater to grow, return to the ocean to spawn

Answer

Catadromous fish like the American eel are born in the ocean (Sargasso Sea), migrate to freshwater rivers and lakes to grow for many years, then return to the ocean as adults to spawn and die.

Question 4

What type of muscle tissue comprises the majority of body mass in most fish and powers burst swimming?

Accepted Answer

White glycolytic (fast-twitch) muscle

Answer

White (fast-twitch, glycolytic) muscle constitutes the bulk of fish body mass and generates the powerful, rapid contractions needed for burst swimming during prey capture and predator escape.

Question 5

How do most cartilaginous fish (sharks and rays) achieve buoyancy in the absence of a swim bladder?

Accepted Answer

By storing large quantities of low-density squalene oil in an enlarged liver

Answer

Cartilaginous fish lack a swim bladder and instead have a very large liver containing squalene and other low-density lipids that provide positive lift and reduce the animal's overall density toward neutral buoyancy.

(CFP) Certified Fisheries Professional Practice Test

(CFP) Certified Fisheries Professional Practice Test

CFP Fish Biology & Physiology 3