Question

Pls. Tell fast the ans of question 17 , 18, and 19

Answer 1

Answer:

Question 17:

The main function of retina in the eye is to act as a receptor. It converts the light coming from objects into Action Potentials (electrical impulses) . These action potentials are transmitted by the optic nerve to the brain.

So, we can say that Retina actually captures the image and transmits it to the brain for proper reception and identification.

Question 18:

Whenever, Ethanol is heated in presence of Conc. Sulphuric Acid at 443 K, Ethene gas is produced.

1. Ethanol = C2H5OH
2. Ethene = C2H4

Question 19:

Importance of DNA copying:

• DNA is a hereditary material.
• It is transferred from parents to offsprings. It is DNA , which codes for the various biomolecules of our body.
• DNA copying helps us to identify Genetic Disorders, helps to identify suspects at crime scene.

Answer 2

Step by step explanation:

Answer 17) The retina is defined as the thin layer of tissue lining the back of the eye internally. It is located within the close proximal area of the optic nerve.

The primary function of the retina is to obtain the light that has been focused by the lens, convert them into respective neural signals and then revert these signals to the brain, for obtaining visual interpretations and recognition respectively.

Answer 18) When ethanol is heated with conc. H2SO4 at 443K, dehydration takes place and ethene is formed. Therefore, concentrated sulphuric acid acts as the dehydrating agent.

Answer 19) DNA copying or the mechanism of DNA replication is necessary in case of reproduction. This mechanism helps in the transfer of information or characteristics from the parent generation to the next generation , i.e. the offspring. It also aids in generating variations in the process of sexual reproduction, thereby, promoting evolution.