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The blood enters and circulates in the interstitial spaces (space between the tissues). The exchange of materials between the cells and the blood is done directly. There are few blood vessels but they are not extensive. The blood vessels are open-ended as they open into the..

Just behind the cornea is a dark coloured muscular diaphragm which has a small circular opening in the middl..

A good source of energy should have the following characteristics: It should do a large amount of work per unit mass or volume - it means that the output energy must be more than the input energy. It should have high calorific value. It should be easily accessible - the energy sourc..

is the external female genitalia. It comprises of the mons veneris, which is the raised pubis. The vaginal opening has two pair of folds on either side. The outer fold is thicker with hair, sweat glands and sebaceous glands and is called labia majora. The inner folds are thinner and devo..

This comprises area which is dedicated for conservation of the environment, natural objects and the wildlife therein. Forestry operations are prohibited and it is open to visitors who are not allowed to disturb or harm the protected plants or animal..

They come from the burning of solid fossil fuels like coal, wood and coke. Many houses and road side eateries still use these fuels. Open burning of wastes also generates ashe..

It is a bag-like structure which ends in an opening called the anus. The rectum stores the undigested food as faecal matter till it can be passed out. The anus is guarded by external and internal sphincter muscle..

There are two types of blood circulatory systems: Open circulatory system Closed circulatory syste..

Characteristics of Sources of Energy - A good source of energy should have the following characteristics: It should do a large amount of work per unit mass or volume - it means that the output energy must be more than the input energy. It should have high calorific value. It should be easily a..

Low light intensity lowers the rate of photosynthesis. As the intensity is increased the rate also increases. However, after reaching an intensity of 10,000 lux (lux is the unit for measuring light intensity) there is no effect on the rate. Very high intensity may, in fact, slow down the rate as i..