Question

Characteristics of group Insecta is
A. Jointed appendages
B. Three pairs of jointed legs
C. Chitinous skeleton
D. Compound eyes

Answer 1

Hint: Insecta or insect are also known as hexapods. Insects classify under the largest phylum called Arthropoda. It covers almost two-third of species in the whole world It includes hexapods, annelids, arachnids, crustaceans, and myriapods, all these have jointed appendages.

Complete answer:
Arthropoda is a combination of two words ‘arthro’ means jointed and ‘pods’ means foot. Some features of Arthropoda phylum are
1. They are bilaterally symmetrical, triploblastic, segments, and coelomates.
2. They have jointed legs.
3. The exoskeleton is made up of chitin.
4. The circulatory system is an open type.
5. Excretion takes place through malpighian tubules.
6. Sensory organs like antennae, compound eyes or simple eyes, statocyst, or balance organs are present.
7. Fertilization is usually internal.
8. They are mostly oviparous.
9. Development may be direct or indirect.
10. Respiratory organs are gills, book gills, or tracheal systems.
Hexapods mean six legs as discussed above insects have six jointed appendages.
So the correct answer is three pairs of jointed legs because all the other options jointed appendages, chitinous exoskeleton, and compound eyes are all the common features of animals that classify under arthropods but only hexapods under Arthropoda phylum have three jointed legs. The main characteristics of the Insecta group are three jointed legs.

Hence the correct option is (B).

Notes: Insects are segmented into head, thorax, and abdomen. The development of insects is indirect means their larva form is not similar to an adult form. Metamorphosis is a process in which insects change their structure and become different from their larva form. Insects are important pollinators. Honey bees, silkworms, and lac insects are some economically important insects.