A vitamin requires cobalt for its activity. The vitamin is

• vitamin B₁₂

• vitamin D

• vitamin B₂

• vitamin A

The bats can fly in the dark because

• they can see the objects in the darkness

• they have weak legs and are likely to be attacked by predators

• they generate flashes of light

• they generate ultrasonic sound waves

The land of maximum biodiversity is

• tropical

• temperate

• monsoonal

• equatorial

204.

How many neck canal cells are found in the archegonium of a fern?

• One

• Two

• Three

• Four

Which angiosperm is vesselless?

• Hydrilla

• Trochodendron

• Maize

• Wheat

Who was the first child born after operative procedure?

• Caesar

• Huxley

• William

• Pasteur

Myrmecology is study of

• Insects

• Ants

• Crustaceans

• Arthropods

Cactus is referred to as

• Hydrophyte

• Mesophyte

• Xerophyte

• Epiphyte

HIV often changes its shape due to the presence of an enzyme called

• reverse transcriptase

• enterokinase

• nucleotidase

• nucleoditase

The cells which are closely associated and interacting with guard cells are

• Transfusion tissue

• Complementary cells

• Subsidiary cells

• Hypodermal cells