2020 - JAMB Biology Past Questions & Answers - page 1

1

The hormone which regulates the amount of glucose in the blood us called?

A

Adrenalin

B

Auxin

C

Insulin

D

Thyroxine

CORRECT OPTION: c
Insulin is a hormone that lowers the level of glucose (a type of sugar) in the blood. It's made by the beta cells of the pancreas and released into the blood when the glucose level goes up, such as after eating. Insulin helps glucose enter the body's cells, where it can be used for energy or stored for future use. Via: https://kidshealth.org/en/parents/insulin.htm
2

Deamination occurs in the?

 

A

Kidney

B

Pancreas

C

Spleen

D

Liver

CORRECT OPTION: d

Deamination is the removal of an amino group from a molecule. Enzymes that catalyse this reaction are called deaminases. ... In situations of excess protein intake, deamination is used to break down amino acids for energy. The amino group is removed from the amino acid and converted to ammonia.

Via Wikipedia

3

In an agricultural ecosystem, the biotic component consist of

A

crops, pests and beneficial insects

B

crops, temperature and humidity

C

pests, beneficial insects and water

D

crops, water and soil

CORRECT OPTION: a

Biotic components, or biotic factors, can be described as any living component that affects another organism or shapes the ecosystem. This includes both animals that consume other organisms within their ecosystem, and the organism that is being consumed. Wikipedia

4

Epiphytes growing on the branches of trees provide an example of the relationship known as?

A

parasitism

B

commensalism

C

saprophytism

D

holophytism

CORRECT OPTION: b

Commensalism is a long-term biological interaction in which members of one species gain benefits while those of the other species neither benefit nor are harmed. Wikipedia

5

The hypha of rhizopus is said to be non-septate because it

A

does not contain chloropyll

B

has no cross wall

C

is vacuoled

D

stores oil globus

CORRECT OPTION: b

Hyphae can form a tangled network called a mycelium and form the thallus (body) of fleshy fungi. Hyphae that have walls between the cells are called septate hyphae; hyphae that lack walls and cell membranes between the cells are called nonseptate or coenocytic hyphae)

Via lumenlearning

6

The function of ribosome in cells is

A

protein synthesis

B

starch synthesis

C

transport of material

D

lipid storage

CORRECT OPTION: a

The ribosome, a cell organelle, functions as a micro-machine for making proteins.

7

In which of the following does external fertilization take place?

A

toad

B

lizard

C

bird

D

cockroach

CORRECT OPTION: a

External fertilization is a mode of reproduction in which a male organism's sperm fertilizes a female organism's egg outside of the female's body. It is contrasted with internal fertilization, in which sperm are introduced via insemination and then combine with an egg inside the body of a female organism. 

Wikipedia

8

The villus in the small intestine is significant because

A

Increases the surface area for absorption

B

increases the surface area for digestion

C

assists in mixing digested food

D

assists in filtering undigested food

CORRECT OPTION: a

Villus, plural villi, in anatomy any of the small, slender, vascular projections that increase the surface area of a membrane. The villi of the small intestine project into the intestinal cavity, greatly increasing the surface area for food absorption and adding digestive secretions.

britannica

9

The butterfly is of great economic importance because

A

of it's use in scientific studies

B

it sucks nectar from flowers

C

it adds to the beauty of the environment

D

it pollinates flowers of crops and other plants

CORRECT OPTION: d

Butterflies play important roles as pollinators to most agricultural crops.

10

The bright colours of the comb and feathers in the peacock are for?

A

sex differentiation

B

beauty

C

courtship

D

defence

CORRECT OPTION: c

The male peacocks display their beautiful fanned trains as part of their courtship behaviour.

Pages: