Biology Questions and Answers

Answer: C

The oath taken by medical graduates comes from Hippocrates.

The Hippocratic Oath binds the physician to act for the patient's benefit, to do no harm and to keep confidence. Modern graduates usually take a revised version, such as the Declaration of Geneva.

Answer: B

A gram of glucose releases about 4 kilocalories.

Carbohydrate and protein each yield about 4 kcal per gram and fat about 9. The complete oxidation of glucose gives \( \mathrm{C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O} \) and about 686 kcal per mole.

Answer: A

Correct answer: Pituitary

The pituitary secretes hormones that regulate the thyroid, adrenal cortex and gonads, which is why it is called the master gland. It is itself directed by the hypothalamus, so the control is layered rather than absolute.

Answer: D

Arthropoda is the largest phylum, with over a million described species - about 80 per cent of all known animals.

It includes insects, crustaceans, arachnids and myriapods, united by a jointed exoskeleton of chitin and jointed limbs. Insects alone outnumber every other group of animals combined.

Answer: A

August Weismann challenged Lamarck's theory of the inheritance of acquired characters.

His germ plasm theory held that the reproductive cells are set apart early and unaffected by what happens to the body. He cut the tails off mice for twenty-two generations, and every litter was born with a full tail.

Answer: D

Exobiology is the study of life beyond the earth - on other planets, satellites and in space generally.

It covers the search for life elsewhere, the conditions under which it could arise, and the survival of terrestrial organisms in space. It is also called astrobiology.

Answer: D

The human body has about 700 named skeletal muscles.

They make up roughly 40 per cent of body weight. The count varies with how finely muscles are subdivided; the figure of 206 belongs to the bones, not the muscles.

Answer: A

Blood is slightly alkaline, at pH 7.35 to 7.45.

It is held there by the bicarbonate buffer, by the lungs regulating carbon dioxide and by the kidneys excreting acid. Outside about 6.8 to 7.8 life cannot continue.

Answer: B

Adrenaline is injected in a cardiac emergency.

It constricts the peripheral vessels, raising the pressure that drives blood to the heart and brain, and stimulates the heart itself to beat faster and harder. It is given intravenously during resuscitation.

Answer: C

The biogenetic law was proposed by Ernst Haeckel in 1866.

It states that ontogeny recapitulates phylogeny - that an embryo passes through stages resembling its ancestors. The law is not accepted as stated, but embryos of related groups do resemble one another closely, which is real evidence of common descent.