Science [2 Mark Questions]

i. Different colours of light bend through different angles with respect to the incident ray as they travel with different speeds while passing through a prism, this phenomenon is known as disperson of light.
ii. X = violet, this colour has minimum wavelength thus suffers maximum deviation, Y = red, as it has maximum wavelength and thus least deviated.

i. As uncle is supplying frogs from his village to laboratories so the number of frog population is decreasing. Frogs eat grasshoppers and mosquitoes. But as the number of frogs population is reduced so the population of grasshoppers and mosquitoes are increasing. So malaria is spread in the village by mosquitoes and grasshoppers are causing damage to the crops.
ii. He must stop the supply of frogs to the laboratories as the reduced frog population is causing an imbalance in the food chain and proper ratio of frogs, grasshoppers and mosquitoes can not be maintained in the ecosystem.

The following figure shows a ray of light incident obliquely. Every medium has a critical angle. When angle of incidence is more than critical angle, the ray of light comes back in the same medium. This phenomenon is called total internal reflection.

a. The separation of oxygenated and deoxygenated blood in mammals and birds is necessary to produce more energy in order to maintain their body temperature at different climatic Conditions.
b. Amphibians can withstand some amounts of blood that is both oxygenated and deoxygenated because they don't require a lot of energy. They alter their body temperature.

i. a. Testis - Anther
b. Sperm - Pollen grains
c. Ovary - Ovary
d. Egg - Ovum
ii. Flowers are the main organs of sexual reproduction. They contain the reproductive organs.