In plant cells, the chloroplast are located

A. inside the cell wall

B. outside the protoplasm

C. within the vacuole

D. within the cytoplasm

In the woody stems, gaseous exchange takes place through the

A. micropyles

B. stomata

C. lenticels

D. vessels

Substance manufactured by the leaves are transported to other parts of the plant through the

A. phloem

B. companion cells

C. sieve tubes

D. cambium

After a meal of yam has been digested, the highest concentration of glucose is to be found in the

A. hepatic artery

B. pulmonary vein

C. hepatic portal vein

D. posterior vena cava

The dark reaction of photosynthesis involves

A. fixation of carbon (IV) oxide to give six-carbon sugar

B. fixation of carbon (IV) oxide with the help of oxygen

C. use of carbon (IV) oxide to produce glucose using ATP

D. fixation of carbon (IV) oxide on chlorophyll using hydrogen

Mammals acclimatize to reduced oxygen content at high altitudes by

A. the stimulation of marrow to reduce the amount of erythrocytes produced

B. increasing the rate at which erythrocytes are destroyed

C. the stimulation of marrow to produce more erythrocytes

D. increasing the break down of the protein portion of the erythrocytes

The modes of nutrition in Nitrobacter, Ascaris and Homo sapiens respectively are

A. photosynthetic , parasitic and holozoic

B. chemosynthetic, parasitic and holozoic

C. photosynthetic, parasitic and heterophytic

D. chemosynthetic, holophytic and holozoic

The richest source of vitamin A are

A. palm oil and groundnut oil

B. palm oil and carrot

C. rice and groundnut oil

D. oranges and carrot

The force that holds water together in the form of a stream within the xylem tube is the

A. cohesion of water molecules to one another by hydrogen bonds

B. force of gravity attacking the water molecules through the hydrogen bonds

C. attraction between the water and xylem osmotic force

D. normal flow of water from the ground with help of gravitational force

Yellowing of leaves is a symptom associated with deficiency of

A. iron, calcium and magnesium

B. nitrogen, sulphur and potassium

C. sulphur, phosphorus and iron

D. magnesium, nitrogen and iron