Question

Briefly explain 2 advantages of bone compared with insect exoskeleton. What is one significant disadvantage of bone?

Answer 1

Both types of skeleton be it endoskeleton made up of bones and cartilage whereas exosketeton made up of scales, calcified shells and chitinous cuticle has its own disadvantages and advantages. Out of all the advantages of the endoskeleton the major of them are:

1) Growth - The endoskeleton made up of cartilage and bones continuously grow with the growth of the body. The bones and cartilages are the living tissue that's why it grows with the development of body. But the exoskeleton is the dead matter which does not grow with the body of insects. Due to which moulting of the exoskeleton take place several times in the life cycle of insects. The newly synthesized exoskeleton is soft initially, making the insect venerable.

2) Weight bearing property - The bones are rigid and strong structure of the body without being to heavy. The bones form almost 15% of the total body weight in a healthy adult. There rigid and strong structure gives as the ability to lift-up and support heavy weight without being heavy. Whereas exoskeleton of insects is heavy as compared to their body weight and less rigid than bones.

Now major disadvantage of endoskeleton is:

1) Less protection - The endoskeleton of bones is present inside the body covering only the vital organs fully or partially. It does not provide any protection for the external environment. Whereas exoskeleton provide protection from the external means. It can protect the insect from cuts and damage from sharp objects whichn is lacking in the endoskeleton made up of bones.