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Why was Charles Darwin's theory of evolution by natural selection not accepted at the time?

There are three main reasons for this, firstly, the 1800s when Charles Darwin lived was a deeply religious time and the idea of evolution challenged the idea of God creating life on Earth. Secondly, not m...

Answered by Amy W. • Biology tutor

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How might an animal be adapted to a cold environment?

An adaptation is a feature or characteristic that allows an organism to live and survive successfully in a habitat.
Animals living in cold environments, such as the polar bear, may have a small surf...

Answered by Amy W. • Biology tutor

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What are the key features of natural selection?

First off we need to understand what natural selection is. Natural selection is the mechanism proposed by Charles Darwin in his theory of evolution.
The key points you need to know for this are:

Answered by Amy W. • Biology tutor

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What is the difference between homozygous and heterozygous?

Homozygous means there are two copies of the same allele present at a specific locus (position) on a chromosome, e.g. two copies of the allele for blue eyes. Whereas, heterozygous means there are two copi...

Answered by Amy W. • Biology tutor

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What is an allele?

Simply put, it is a form of a gene which can lead to different phenotypes, e.g. eye colour. There is one allele that codes for blue eyes and another allele that codes for brown eyes.

Answered by Amy W. • Biology tutor

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