Vestigial Organs.pptx

Ppt

1. Vestigial Organs

2. Introduction Definition: Vestigial organs are those organs that have ceased to be of any use to the possessor but still persist after many generations in a reduced form.

3. Wisdom Teeth Wisdom teeth are the last molars on each side of both the jaws. The wisdom teeth are so called as they appear last at an age of about 17-20 years , when the body reaches maturity. They are smaller and less complex than other molars. We hardly use our wisdom teeth for chewing our food

4. Vermiform Appendix Vermiform appendix projects from the blind end of the caecum (first part of large intestine) as a narrow worm-like tube. It is a functionless (vestigial) organ in humans, but its corresponding organ in herbivorous mammals (like sheep) is quite helpful in digesting cellulose

5. Pinna Pinna is the projecting lobe-like part of the external ear which simply provides a passage from auditory canal leading to the ear drum. We can not move the pinna to gather the sound waves which is its main function in other mammals due to the complete but poorly developed and functionless muscles are present in human beings in connection with pinna.

6. Q1 Read the following and answer the question The diet of the human ancestors was a broad range of foods, including some tougher foods like leaves, woody plants, and some animal tissues . While the diet of modern man consists of fruits, grains, nuts, vegetables, tubers (for example, potatoes), meats. (i) Why do we hardly use our wisdom tooth? (ii) What lead to The Vermiform appendix becoming a vestigial organ?

7. Q2 Ravi soon after his 18th birthday started experiencing jaw pain and had difficulties opening his mouth, what could have caused this?

8. Q3 Why has our body not completely removed Vestigial Organs During our evolution.