In mammals, the exchange of nutrients and metabolic products occurs in the

A. lymph

B. lungs

C. heart

D. liver

The part of the stomach nearer the gullet is called th

A. epiglottis

B. cardiac spincter

C. duodenum

D. pyloric sphincter

Trace elements are required by plants mainly for the

A. formation of pigments and enzymes

B. production of energy and hormones

C. manufactured of carbohydrates

D. manufacture of proteins

The part that is similar to the bone is labelled

A. IV

B. III

C. II

D. I

The part labelled I and II constitute the

A. Crown

B. neck

C. root

D. gum

A food substance was treated with a few drops of Sudan III solution and a red coloration was obtained. The food contained

A. protein

B. starch

C. fat

D. mineral salt

Oozing out of water from the leaves of plants in a humid environment is known as

A. transpiration

B. osmosis

C. pinocytosis

D. guttation

The element that is essential for the coagulation of blood is

A. potassium

B. calcium

C. phosphorus

D. iron

Anaerobic respiration differs from aerobic respiration by the production of

A. less amount of energy and water

B. greater amount of energy and alcohol

C. less amount of energy and alcohol

D. greater amount of energy and water

Stomatal pores open when there is

A. an increase in the sugar content of guard cells

B. a decreases in the osmotic concentration of the guard cell

C. a decrease in the sugar content of mesophyll cells

D. an increase in the sugar content of mesophyll cells