Q 01/05

Skin is the body's heaviest organ, so which is the heaviest organ inside the body?

A) The brain

B) The liver

C) The lungs

D) The heart

Answer · why

B) The liver

The liver, at about 1.5 kg, leads the internal organs, but the skin easily outweighs it: at 3.5 to 10 kg it makes up around a seventh of an adult's bo...

Q 02/05

Spread out flat, an average adult's skin would roughly cover what?

A) A pillowcase

B) A single bed

C) A parking space

D) A tennis court

Answer · why

B) A single bed

A single bed: adult skin covers 1.5 to 2 square metres, about one mattress top, and doctors work out each patient's figure from height and weight to s...

Q 03/05

What are the three primary layers of human skin, from outside in?

A) Epidermis, dermis, hypodermis

B) Ectoderm, mesoderm, endoderm

C) Epicardium, myocardium, endocardium

D) Dura mater, arachnoid, pia mater

Answer · why

A) Epidermis, dermis, hypodermis

Epidermis, dermis, hypodermis: a thin barrier that is shed constantly, a tough middle layer that carries the nerves and sweat glands, and a bed of fat...

Q 04/05

The prefix 'epi' in epidermis comes from Greek and means what?

A) Underneath

B) Over or upon

C) Deep within

D) All around

Answer · why

B) Over or upon

Over or upon: Greek epi, 'upon', plus derma, 'skin', makes the epidermis the layer on top, just as an epicentre is the point on the surface directly a...

Q 05/05

With no blood supply of its own, where does the epidermis get almost all of its oxygen?

A) Lymph seeping up from below

B) The surrounding air

C) Oil from sebaceous glands

D) Sweat drawn back through pores

Answer · why

B) The surrounding air

The surrounding air: oxygen diffuses straight in and supplies the epidermis almost entirely, so the blood beneath adds little, although the cells' foo...