JAMB Biology Past Questions & Answers - Page 163

811.

Mycorrhiza promotes plant growth by?

A.

absorbing inorganic ions from the soil

B.

protecting it from infection

C.

helping it to utilize atmospheric nitrogen

D.

serving as a growth regulator

Correct answer is A

Mycorrhizal fungi allow plants to draw more nutrients and water from the soil.

They also increase plant tolerance to different environmental stresses.

812.

A food chain always begins with a

A.

consumer

B.

decomposer

C.

producer

D.

primary consumer

Correct answer is C

No explanation has been provided for this answer.

813.

I. Stomata → Spirogyra
II. Alveoli → Earthworm
III. Malpighian tubule → Mammal
IV. Contractile vacuole → Protozoa.

Which of the above structures is correctly matched with the organisms in which it is found?

A.

lll

B.

ll

C.

l

D.

IV

Correct answer is D

Ameoba and paramecium are examples of Protozoa.

An Ameoba gets rid of excess water that enters its cell by using a Contractile Vacoule.

814.

The part of the human gut that has an acidic content is the?

A.

stomach

B.

duodenum

C.

ileum

D.

colon

Correct answer is A

The stomach is very acidic, with a pH of 3.5 or below, so it can break down food.

815.

Chemosynthetic organisms are capable of manufacturing their food from simple inorganic substances through what process?

A.

oxidation

B.

denitrification

C.

reduction

D.

phosphorylation

Correct answer is A

In biochemistry, chemosynthesis is the biological conversion of one or more carbon molecules (usually carbon dioxide or methane) and nutrients into organic matter using the oxidation of inorganic (e.g. hydrogen gas, hydrogen sulfide) or methane as a source of energy, rather than sunlight, as in photosynthesis.