Q 01/05

Which giant cactus of the Sonoran Desert may not sprout its first arm until it is 75 years old?

A) Organ pipe

B) Saguaro

C) Cardón

D) Senita

Answer · why

B) Saguaro

Saguaro cacti are the largest in the United States, yet some never grow an arm at all, and the tallest one ever measured had none.

Q 02/05

Which spiky source of tequila is often mistaken for a cactus but belongs to the asparagus family?

A) Agave

B) Aloe

C) Yucca

D) Ocotillo

Answer · why

A) Agave

Agave and cacti look alike because both adapted to dry places, probably a case of convergent evolution; they are not close relatives.

Q 03/05

On the flag of Mexico, which creature perches on a cactus while devouring a snake?

A) A condor

B) A falcon

C) An eagle

D) A quetzal

Answer · why

C) An eagle

An eagle on a cactus was, in Aztec legend, the sign that showed the wandering people where to found their city.

Q 04/05

Pitaya, the pink-skinned harvest of a climbing cactus from Mexico and Central America, is better known by which name?

A) Mangosteen

B) Rambutan

C) Passion fruit

D) Dragon fruit

Answer · why

D) Dragon fruit

Dragon fruit grows on a cactus that winds around nearby trees for support and can climb 8 to 10 meters off the ground.

Q 05/05

Thorns are modified branches, botanists say, while cactus spines are modified versions of which plant part?

A) Roots

B) Leaves

C) Petals

D) Bark

Answer · why

B) Leaves

Leaves reshaped into spines lose far less water, and the spines also shade the cactus and keep hungry animals away.