Biology Questions and Answers

Answer: D

The one that is not an ape is the langur.

Apes have no tail, and include the lesser apes (gibbons) and the great apes (orangutans, gorillas, chimpanzees and bonobos). The langur is an Old World monkey with a long tail, common across India.

The gibbon is a lesser ape, while the orangutan (printed 'Urangutan') and the gorilla are great apes, so all three are apes.

Answer: D

The hormone is epinephrine (adrenaline).

Epinephrine, released by the adrenal medulla in the fight-or-flight response, acts on the heart's beta-1 receptors to increase both the heart rate and the force of contraction. It is the classic cardiac stimulant hormone and is used in emergencies such as cardiac arrest and anaphylaxis.

Thyroxine also raises the heart rate over time, as part of its general effect on metabolism, but it is not the hormone identified with direct stimulation of the heart. Estrone is an oestrogen, and erythropoietin stimulates the production of red blood cells.

Answer: C

Insulin is secreted by the Pancreas.

Insulin is a hormone made by the beta cells of the islets of Langerhans in the pancreas. It lowers blood sugar by helping cells take up glucose, and too little of it causes diabetes.

The liver stores glucose as glycogen and makes bile, the gall bladder stores that bile, and the kidneys filter the blood. None of them secretes insulin.

Answer: B

Entomology is the study of insects.

The word comes from the Greek entomon, insect (literally 'cut into', from the segmented body), and -logia, study. Entomology covers insect structure, behaviour, life cycles and their role as pests and disease carriers.

The origin and history of technical and scientific terms is part of etymology (terminology), the formation of rocks is petrology, and human behaviour is studied in psychology.

Answer: D

The universal donor is blood group O.

Group O red cells carry neither the A nor the B antigen, so they are not attacked by the anti-A or anti-B antibodies of any recipient. Strictly, O negative is the universal donor for red cells, because it also lacks the Rh antigen.

Group AB is the universal recipient, since its plasma has no anti-A or anti-B antibodies. Groups A and B can be given only to compatible recipients.

Answer: A

The 'Flame of the Forest' is Palash.

Palash (Butea monosperma) sheds its leaves in late winter and is then covered with bright orange-red flowers, so a forest of palash in bloom looks as if it is on fire. It is the state flower of Jharkhand and Uttar Pradesh.

Rohida (Tecomella undulata) is the state flower of Rajasthan, Semal is the red silk-cotton tree, and orchids are a whole family of plants, not this tree.

Answer: C

Such cells are called prokaryotic.

Prokaryotic cells, found in bacteria and cyanobacteria (blue-green algae), have no true nucleus: their genetic material lies in a region of the cytoplasm called the nucleoid, with no nuclear membrane around it. They also lack membrane-bound organelles such as mitochondria.

Eukaryotic cells, in plants, animals, fungi and protists, have a true nucleus enclosed by a nuclear membrane. Mononucleate and multinucleate describe how many nuclei a cell has, so both assume a nucleus is present.

Answer: C

Covid-19 is treated as a pandemic disease.

A pandemic is an epidemic that spreads across many countries and continents. The World Health Organization declared the Covid-19 outbreak a pandemic on 11 March 2020, after it had spread worldwide.

An epidemic is a sudden rise in cases in a particular region, and an endemic disease is one constantly present in an area, such as malaria in parts of the tropics. Covid-19 is caused by a virus that spreads from person to person, so it is not a non-communicable disease.

Answer: D

Iodine deficiency causes Goitre.

The thyroid gland needs iodine to make the hormone thyroxine. When the diet lacks iodine, the gland enlarges in an attempt to make more hormone, producing a swelling in the neck called goitre. Iodised salt is used to prevent it.

Anaemia is usually caused by a lack of iron, beriberi by a lack of vitamin B1 (thiamine), and scurvy by a lack of vitamin C.

Answer: A

If the heart rate increases, the pulse rate increases.

The pulse is the wave of expansion that passes along an artery each time the heart contracts and pushes blood into it. Each heartbeat therefore produces one pulse, so the pulse rate felt at the wrist equals the heart rate and rises and falls with it.

For the pulse rate to fall, stop or stay constant while the heart beats faster would break this one-to-one link, so the other three options are wrong.