Q 01/05

Which structure do prokaryotic cells such as bacteria lack?

A) Ribosomes

B) Cell membrane

C) Nucleus

D) Cytoplasm

Answer · why

C) Nucleus

The nucleus is what bacteria lack: their DNA sits loose in a region called the nucleoid, so the cell can start building a protein from a gene while th...

Q 02/05

Which pair of sex chromosomes do human males typically carry?

A) XX

B) XY

C) ZW

D) ZZ

Answer · why

B) XY

XY is the male pair in humans, but birds do it the other way round: there it is the females that carry the mismatched pair, called ZW, while males hav...

Q 03/05

Which carnivorous plant catches insects between hinged leaves that snap shut?

A) Pitcher plant

B) Sundew

C) Venus flytrap

D) Bladderwort

Answer · why

C) Venus flytrap

The Venus flytrap closes only when its trigger hairs are touched twice in quick succession, a safeguard that stops the plant wasting energy by snappin...

Q 04/05

What is the largest organ in the human body?

A) Skin

B) Brain

C) Liver

D) Lungs

Answer · why

A) Skin

Skin is the body's largest organ and its protective barrier, which is why severe burns are so dangerous: with that covering gone, fluid leaks out of t...

Q 05/05

Which condition results from an extra chromosome 21?

A) Cystic fibrosis

B) Down syndrome

C) Huntington's disease

D) Haemophilia

Answer · why

B) Down syndrome

Down syndrome arises when a child inherits three copies of chromosome 21 instead of the usual two, giving 47 chromosomes where most people have 46; th...