Biology Questions and Answers

Answer: A

Chemical reactions converted simple organic compounds into macromolecules.

Amino acids polymerised into proteins and nucleotides into nucleic acids, probably on clay surfaces or in the mineral pores of hydrothermal vents. From these came the first self-replicating systems and eventually cells.

Answer: D

The study of how traits are transmitted from one generation to the next is genetics.

Mendel founded it with his work on peas; William Bateson coined the name in 1905. Homology and analogy belong to comparative anatomy, ecology to the study of organisms in their surroundings.

Answer: C

Deductive reasoning applies general principles to predict or explain specific cases.

Its conclusion follows necessarily from its premises: if the general rule is true, the particular consequence must be. Inductive reasoning runs the other way, from particular observations to a general rule.

Answer: D

Darwin concluded that populations fail to reach their reproductive potential because of selective pressures.

Every species could increase geometrically, yet numbers stay roughly stable. The difference is made up by deaths from competition, predation, disease and shortage - and which individuals die is not random.

Answer: B

The wrong statement is that in oomycetes the female gamete is smaller and motile while the male is larger and non-motile - it is exactly the other way round.

In oogamy, which the oomycetes show, the female gamete is the larger and non-motile one and the male the small motile one.

Answer: A

Darwin's evidence came from his own observations and from information supplied by others.

The Beagle voyage gave him the fossils and the island species, but he also drew on twenty years of correspondence with breeders, naturalists and collectors, and on Lyell's geology and Malthus's essay on population.

Answer: A

Fertilisation is the fusion of a male gamete with the egg cell.

The result is the diploid zygote. In flowering plants it follows the growth of the pollen tube down the style; the second male gamete fuses with the polar nuclei to form the endosperm, which is why the process is called double fertilisation.

Answer: C

In science either deductive or inductive reasoning, or both, may be used.

Induction generalises from observations into a hypothesis; deduction then draws from that hypothesis a prediction which can be tested. The two work together in the cycle of hypothesis and test.

Answer: A

The scientific method is not a rigid set of logical steps.

It involves a suspicion of what the truth might be, an educated guess, and a great deal of imagination and insight. The textbook sequence of steps is a simplification of what scientists actually do.

Answer: B

Proving theories are true is not part of the scientific process.

Evidence can refute a theory but never prove it, since the next observation may contradict it. A theory that survives repeated attempts to refute it is provisionally accepted, not established.