JAMB Biology Past Questions & Answers - Page 346

1,726.

Exoskeleton is NOT found in the

A.

Maggot

B.

Mosquito larva

C.

Earth worm

D.

Caterpillar

E.

Termite

Correct answer is C

No explanation has been provided for this answer.

1,727.

The dorsal and anal fins of fish are used for 

A.

Upward movement

B.

Controlling rolling

C.

Downward movement

D.

Steering

E.

Buoyancy

Correct answer is B

No explanation has been provided for this answer.

1,728.

Which of the following statement is NOT true of enzymes? They

A.

Are proteins

B.

Need cofactors to activate them

C.

Are sensitive in their action

D.

Are specific in their action

E.

Can withstand high temperature

Correct answer is E

No explanation has been provided for this answer.

1,729.

Osmosis can be defined as the movement of 

A.

Molecules from solution of higher concentration to low concentration

B.

Molecules from solution of low concentration to high concentration

C.

Water from solution of high concentration to low concentration

D.

Water across a semi-permeable membrane from solution of low concentration to high concentration

E.

Water across a semi-permeable membrane from solution of high concentration to low concentration

Correct answer is D

Osmosis is a special case of diffusion in which only water molecules move from a region of higher to lower water potential through a semi-permeable membrane.

1,730.

The exchange of genes between homologous chromosomes is called

A.

test cross

B.

back cross

C.

crossing-over

D.

mutation

Correct answer is C

No explanation has been provided for this answer.