Why zebra fish experience similar genetic disease as human

70% of the human genome is the same as found in the zebrafish.

Explanation:

The genetic make-up of zebrafish has shown that 70% of the human genetic make-up is similar to the genetic makeup of zebrafish. The protein coding of genes in both vertebrates is related.

Almost 84% of the genes which cause human genetic diseases are correlated with zebrafish genes. That's why zebrafish experiences the same genetic diseases as humans.

the answer would be 2, if crossing over doesn’t occur 2 out of 4 of the daughter cells will have that allele.

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