Q 01/05

Which hormone was first injected into a patient in 1922, when Toronto doctors treated a dying 14-year-old boy?

A) Adrenaline

B) Insulin

C) Cortisone

D) Thyroxine

Answer · why

B) Insulin

Insulin had been isolated from dog pancreas only months earlier by Banting and Best. The extract given to the boy was so impure that he had a severe a...

Q 02/05

Which protein, the most abundant in mammals, turns into gelatin when animal bones and hides are boiled?

A) Albumin

B) Fibronectin

C) Collagen

D) Elastin

Answer · why

C) Collagen

Collagen makes up 25% to 35% of all the protein in a mammal's body. It often survives in ancient bones, so it may be one of the most abundant proteins...

Q 03/05

Which tough protein forms human hair and fingernails as well as the horns of cattle and rhinos?

A) Keratin

B) Fibroin

C) Myosin

D) Tubulin

Answer · why

A) Keratin

Keratin is rich in sulfur, which is why burning hair smells so pungent. The same protein family builds feathers, hooves, claws and the slime threads o...

Q 04/05

Which stimulant fights drowsiness by blocking brain receptors for adenosine, which builds up during waking hours?

A) Nicotine

B) Taurine

C) Ephedrine

D) Caffeine

Answer · why

D) Caffeine

Caffeine sits in the adenosine receptor without switching it on, so the drowsiness signal never arrives. Heavy use makes the body produce more of thos...

Q 05/05

Which sugar in milk are around 65% of adults worldwide unable to absorb fully?

A) Maltose

B) Lactose

C) Fructose

D) Dextrose

Answer · why

B) Lactose

Lactose is digested by an enzyme that most people make less of after infancy. Struggling with milk as an adult is the ancestral human state, and toler...