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Home > Biology > Inheritance > What is inheritance?


What is inheritance?


The genotype of an organism tells us which forms ofthe gene are present.

The different forms a gene can take are known as the alleles. Offspring receive one allele of a gene from each parent, these alleles may be the same or different. Only one of the two alleles can go into a gamete, and this is a random choice.


When we are describing crosses we can save a lot of writing by letting the genes be represented by letters. The capital letter always represents the dominant form of the gene (the dominant allele). The small letter always represents the recessive allele. The genotype can then be written as two letters e.g.(Bb) or (Dd).


Click this audio clip to find out about how genes are passed down.

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Video clip about the discovery of genetics and inheritance


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