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Why is the number of chromosomes an organisms has an even number?

Answer 1

The reason why the majority of organisms have an even number of chromosomes is because chromosomes are in pairs. A human, for instance, will have half its chromosomes from the father, and half from its mother.

There are exceptions to the rule. For instance, an individual with Down Syndrome will have 47 chromosomes instead of 46, because they have trisomy 21 (three copies of the 21st chromosome, instead of just two).

Another exception would be polyploidy , which occurs when organisms have more pairs of chromosomes than a diploid cell does.

Below is a picture to help visualize polyploidy. An example of a haploid cell would be a gamete (a sperm cell, for instance), and a diploid cell would be a skin cell of a person with 46 chromosomes.

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Answer 2

Vivian Aronson

The number of chromosomes in organisms is typically even because they are inherited in pairs, with one chromosome coming from each parent during sexual reproduction. This pairing ensures that offspring receive a complete set of genetic information.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.