REPRODUCTION
REPRODUCTION IN ORGANISMS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Because it takes four gametes to make a zygote.
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Because half of an offspring’s DNA will come from each parent.
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Because they are the only cells not doing a job.
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They are not haploid, they are diploid.
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Detailed explanation-1: -The nuclei re-form, and new nuclear membranes develop. This process results in four new cells, or gametes. Each gamete contains only one chromosome from each homologous pair. This makes the cell haploid, meaning that it has half the chromosome number of the original diploid cell.
Detailed explanation-2: -Gametes are reproductive cells, such as sperm and egg. As gametes are produced, the number of chromosomes must be reduced by half. Why? The zygote must contain genetic information from the mother and from the father, so the gametes must contain half of the chromosomes found in normal body cells.
Detailed explanation-3: -It is important that gametes have half the amount of DNA (haploid) so that at fertilisation when the egg and sperm combine it results in a cell with a full complement of DNA. Errors can occur during meiosis producing gametes with an extra or missing chromosome.
Detailed explanation-4: -Gametes must be haploid because they will be combining with another gamete. Sexual reproduction works to increase genetic diversity by having two haploid gametes combine to form a new organism that has a different combination of genes than either of its parents.