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Immunity is the ability for the body to respond to familiar pathogens so quickly that they are not able to cause a physical disease, meaning we can be infected for a short period of time, and not notic...

Homeostasis is defined as the maintenance of a constant internal environment in the body. 

An example of this would be the blood glucose level:

After a meal, a person's bloo...

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Within all populations, there is variation.

This is due to di...

Once a month, following ripening, a single egg is released from a woman's ovaries during the menstrual cycle, with the hope of fertilisation. During the act of sexual reproduction, the father's sperm i...

A gene is a section of DNA or RNA that codes for a protein. Alleles are different versions of the gene.  For example, if a gene coding for a particular enzyme mutated, then there would be two alleles o...