CELL DIVISION
MEIOSIS
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
In humans, each of the 22 maternal autosomes has a homologous paternal chromosome.
|
|
|
In humans, the 23rd pair, the sex chromosomes, determines whether the person is female (XX) or male (XY).
|
|
|
Single, haploid (n) sets of chromosomes in ovum and sperm unite during fertilization, forming a diploid (2n), single-celled zygote.
|
|
|
At sexual maturity, ovaries and testes produce diploid gametes by meiosis.
|
Detailed explanation-1: -Answer and Explanation: The false statement is option D. At sexual maturity, ovaries and testes produce haploid gametes by meiosis. Meiosis is the cell division that is also known as the reductional division.
Detailed explanation-2: -At sexual maturity, ovaries and testes (the gonads) produce haploid gamete by meiosis, each gamete containing a single set of 23 chromosomes (n=23). During fertilization, an egg and sperm unite, forming a diploid (2n = 46) single celled zygote, which develops into a multicellular organism by mitosis.
Detailed explanation-3: -Meiosis is a type of cell division that reduces the number of chromosomes in the parent cell by half and produces four gamete cells. This process is required to produce egg and sperm cells for sexual reproduction.
Detailed explanation-4: -Answer and Explanation: Yes, gametes are always produced via meiosis. This is the process whereby a single diploid cell is divided twice to create 4 genetically unique haploid cells. In fact, meiosis only occurs in the body to produce gametes.
Detailed explanation-5: -Gametes must be produced by meiosis for sexual reproduction because the numbers of chromosomes are reduced to half during meiosis and then the normal diploid numbers of chromosomes are regained during the process of fertilization.