Biology Questions and Answers

Answer: A

The speech centre lies in the frontal lobe.

Broca's area, in the lower frontal lobe of the dominant hemisphere - usually the left - controls the production of speech. Wernicke's area, in the temporal lobe, handles comprehension, and damage to the two gives quite different kinds of aphasia.

Answer: A

Carbon dioxide and methane are the principal greenhouse gases from human activity.

Both are triatomic or polyatomic molecules that absorb infrared radiation. Methane traps far more heat per molecule but is present in much smaller amount and lasts about a decade, while carbon dioxide persists for centuries.

Answer: D

A mushroom is saprophytic.

It has no chlorophyll and cannot photosynthesise, so it secretes enzymes onto dead organic matter and absorbs the digested products. The mushroom itself is only the fruiting body; the feeding mycelium is spread through the substrate.

Answer: C

Pedology is the study of soil - its formation, classification and distribution.

The name comes from the Greek pedon, ground. It is not to be confused with pedagogy, the study of teaching.

Answer: A

Our major foods, fibres, spices, fruits and beverages come from flowering plants, the angiosperms.

They are the dominant land plants, with about 300,000 species, and include every cereal, pulse, oilseed and fruit crop. Gymnosperms supply timber and resin but almost no food.

Answer: D

The study of the heart is cardiology, from the Greek kardia.

It covers heart disease, its diagnosis and treatment. Dermatology deals with skin and demography with populations.

Answer: D

Primary phloem develops from the provascular (procambial) tissue.

The procambium is the primary meristem laid down behind the growing point; it gives rise to primary xylem inward and primary phloem outward. Secondary phloem comes later, from the vascular cambium.

Answer: C

Goitre is caused by a lack of iodine.

Iodine is needed to make thyroxine; without it the thyroid enlarges as it tries to compensate, producing the swelling in the neck. In children the deficiency also stunts growth and mental development, which is why salt is iodised.

Answer: A

Genes are situated on chromosomes.

Each chromosome is a single long DNA molecule with its associated proteins, and a gene is a stretch of that DNA. Sutton and Boveri proposed the chromosome theory of inheritance in 1902, and Morgan proved it with Drosophila.

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.