Basics of Biology

1. What are enzymes? Name any one enzyme of our digestive system and write its function. Answer. Enzymes are biological catalysts. Catalysts are proteins that increase the rate of chemical reactions without being used up.    For example: Amylase catalyses the breakdown of starch into sugars in the mouth and small intestine      2.  (i) Write the balanced chemical equation for the process of photosynthesis,  Answer.  Photosynthesis can be represented using a chemical equation. The overall balanced equation is                         6CO 2   +   12H 2 O            Sunlight               C 6 H 12 O 6 + 6H 2 0 + 6O 2    (ii) When do the desert plants take up carbon dioxide and perform      photosynthesis?    Answer.    Desert plants open up their stomata during night and take in CO 2 . Stomata remains close during the day time to prevent the loss of water by transpiration. They store the CO 2 in their cells until the sun comes out and they can carry on with photosynthesis duri

Circadian Clock in Mice controls by Sodium,   New Study Reveals. A new research published this week in the journal Nature shows that injection of salt mice ( hypertonic saline ) leads to activation of neurons in the suprachiasmatic nucleus, the circadian master clock for the brain. Our circadian clock or circadian rhythm adapts the cells and organs of our body at various times of the day to change requirements. Circadian rhythm disturbance due to jetlag or shift work may cause negative health consequences. Light the primary factor that regulates our circadian clock is clearly defined, it was unclear whether or how physiological factors could regulate the suprachiasmatic nucleus. "With our analysis we are the first to show that the physiological signals in the suprachiasmatic heart can actually control clock times," said Professor Charles Bourque, a researcher at the McGill University Health Center's research center. Professor Bourque and PhD

What are life processes ??   The maintenance functions of living organism must go on even when they are not doing anything particular. Even when we are just sitting in class, even we are just asleep; this maintenance job has to go on. The processes which together perform this maintenance job our life processes.  Since these maintenance processes are needed to prevent damage and break-down, energy is needed for them. This energy comes from outside the body of the individual organism. So there must be a process to transfer a source of energy from outside the body of the organism, which we called food, to the inside, a process we commonly called nutrition . If the body size of the organism is to grow, additional raw material will also be needed from outside. Since life on earth depends on carbon-based. molecules, most of these food sources are also carbon-based. Depending on the complexity of these carbon sources different organisms can then use different kinds of nutritional pro