Describe how natural selection can sometimes lead to the persistence of harmful or even lethal alleles. include an example.

Heterozygosity of genes sometimes allows natural selection to maintain deleterious alleles. Sickle cell anemia is only exhibited by people who carry both alleles as recessive.
The recessive/recessive allele can become advantageous in a different environment or time. Sickle cell recessive allele protects their carrier against acquiring malaria.

When you are making a guess you are forming a hypothesis

What is the difference between cytokinesis in plant and animal cells? animal cells dived by a cleavage furrow. plant cells divide by a cell plate that eventually becomes the cell wall. cytoplasm and cell membranes are necessary for cytokinesis in both plant and animals.