Lab quizzes

Question 1

What are mensual characters?

Answer 1

Mensual characters:

• also called morphometric characters
• measured - don’t give discrete values (i.e. can have decimals)
• ex: length of fish

Question 2

What are meristic characters?

Answer 2

Meristic character:

• definite, discrete value
• counted rather than measured
• ex: number of dorsal rays

Question 3

Name one morphological characteristic that can be used to describe the diet of different fish.

Answer 3

Size and protrusibility of the mouth of a fish

- indicates diet and foraging behaviour

Question 4

Why is is important to study gut content of fish species?

Answer 4

Allows one to determine the diet of fish which is pertinent for trophic studies

Question 5

Name 3 kinds of fins and describe their location using scientific language.

Answer 5

Dorsal fin - located dorsal on the fish
Pelvic fin - located ventrally
Caudal fin - located on posterior part of fish
(Pectoral fin - anterior)

Question 6

Compare the liver of the shark and perch. How are they similar, how are they different?

Answer 6

Similar:
- both have an anterior origin

Shark:

• grey, dark
• 3 lobes
• large

Perch:

• pink
• smaller
• 1 lobe

Question 7

What are two ways of estimating age and growth rates of fish?

Answer 7

1) Peterson method: look at actual sizes of of fish populations to estimate growth rate/age
2) Look at scales/otoliths to estimate growth rate/age

Question 8

Give one reason why growth rates and age structures of wild populations are studied.

Answer 8

Provides an idea of the growth rate of a population for establishing catch limits

Question 9

Define cohort.

Answer 9

Group/population of fish that are born in the same year/