Question

One pair of wings occur in
a. Dragonfly
b. Housefly
c. Mayfly
d. Butterfly

Answer 1

Hint: Insects develop wings from the exoskeleton as a result of adult maturation. They are found on the second and the third thoracic segment or commonly called mesothorax and metathorax. This enables the flies to fly.

Complete answer:
> Option A:
Dragonflies have two pairs of wings and are similar in size. In order to fly, dragonflies angle their body upward like a helicopter and fly backward and use their wings to pull their body backward with an appropriate amount of force. Their wings are mostly composed of veins and membranes that give a complex and versatile design to the wings of dragonflies.

> Option B:
Housefly has two wings or one pair of wings as it belongs to the order Diptera. The hind pair is reduced to the halteres that are used for balance and flight stability by flapping the halters. The wings of the housefly are yellowish and translucent. The lobe, calypter at the back of the wing covers the haltere. The fly can only fly in circles if the haltere is removed.

> Option C:
Mayflies have two pairs of wings but unlike dragonflies, they are not similar in size. The hind wings of the mayflies are smaller than the forewings. They may be vestigial or may be absent. They have triangular membranous wings that are covered with veins. The second segment of the thorax bearing forewings is enlarged to hold the flight muscles.

> Option D:
Butterflies have four wings or two pairs of wings, two on each side divided into two forewings and two hindwings. The wings are attached to the second and third thoracic segments (the meso- and meta-thorax) that enable the flies to fly. The wings move up and down in a figure-eight pattern when the butterflies take a flight. Butterfly wings are made up of two chitinous layers (membranes) and are covered by thousands of colorful scales and hairs.

Hence, the correct answer is option (B).

Note: Halteres can rapidly oscillate along with the wings and work like operating structures and the insect uses this vibration as a sensation to locate themselves in the space. Like houseflies, horseflies, crane flies, and hoverflies also have one pair of wings.