If there are 20 centromeres in a cell how many chromosomes are there?

20

Explanation:

each chromosome has 1 centromere its a 1 to 1 ratio

humans are now responsible for causing changes in the environment that hurt animals and plant species. we take up more space on earth for our homes and cities. we pollute habitats. human activity often changes or destroys the habitats that plants and animals need to survive.

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