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A reflex action is the body's rapid, involuntary response to external stimuli, often used in order to protect it from immediate harm. First, a receptor detects a stimulus, such as a heat source which could b...

First of all, it is important to define osmosis. If you have two solutions separated only by a semi-permeable membrane, and one solution is more concentrated than the other, then water will move from the les...

Different phenotypes can be generated without changes to the genotype through a process called Epigenetics. Epigenetics, meaning “above genes”, is the study of changes to the phenotype caused by changes in g...

For a trait to evolve, firstly, there has to be genetic variation among individuals, which will lead to differences in phenotype and cause differences in fitness in a particular environment. These difference...

DNA, deoxyribonucleic acid, is responsible for storing genetic information and is composed of a chain of nucleotides. Each nucleotide is formed by a nitrogen base, a phosphate backbone and a sugar. There are...