proposed regulation changes

Different living organisms tide over very low or very high temperature conditions differently. For E.g., i) Encystment It involves the formation of a hard and chitinous protective coat called cyst, around the body. It is commonly seen in amoeba, euglena. ii) Hibernation (winter sleep) Some animals ..

The water level in the blood changes the volume of the blood which affects the blood pressur..

Role Of Hormones As Messengers And Regulators - Hormones are informational molecules. They are secreted in response to changes in the environment inside or outside the body. These are released into the extracellular fluid, where they are diffused into the blood stream. The latte..

Gene Regulation in Eukaryotes - In eukaryotes, the genes that code for the enzymes needed to catalyse the various steps of a particular metabolic pathway may not be adjacent or even be in different chromosomes. However, these genes are regulated by operon model as in bacteria. B..

The arterial blood pressure becomes very high because the stiff walls cannot regulate the pressure changes. This is called hypertension or high blood pressu..

When scientists started exploring matter, they realised that matter can be divided into smaller and still smaller particles. What was the ultimate particle like? They discovered that the smallest particle of an element that maintains its chemical identity through all chemical and physical cha..

This was proposed by Weismann who did not agree with Lamarck's theory of inheritance of acquired characters. To prove his point, he cut off the tails of many successive generations of mice. This resulted in forced disuse of the tail. According to the theory of use and disuse, the tails s..

Protein synthesis is a controlled process in which a given protein is synthesised in the cell only when it is necessary. When a particular protein is to be synthesised the specific gene has to express and initiate transcription. The mechanism that stimulates the expression of certain genes ..

Since Darwin's theory failed to explain certain facts, particularly the source of variations, several scientists started looking for bridging the lacuna in the theory. One such effort is the mutation theory proposed by Victor Hugo DeVries in 1902. According to this theory, new species ar..

Summary - Growth is one of the most fundamental characteristics of living organisms. It is accompanied by differentiation. The growth cycle of an annual monocarpic angiosperm begins with the zygote which undergoes a period of dormancy. Later, the dormant embryo develops into a seedling which grows ..