EMBRYOLOGY
CHROMOSOMES AND CELL DIVISIONS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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46
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23
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72
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10
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Detailed explanation-1: -In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Twenty-two of these pairs, called autosomes, look the same in both males and females.
Detailed explanation-2: -The only human cells that do not contain pairs of chromosomes are reproductive cells, or gametes, which carry just one copy of each chromosome. When two reproductive cells unite, they become a single cell that contains two copies of each chromosome.
Detailed explanation-3: -The 23rd pair of chromosomes are two special chromosomes, X and Y, that determine our sex. Females have a pair of X chromosomes (46, XX), whereas males have one X and one Y chromosomes (46, XY). Chromosomes are made of DNA, and genes are special units of chromosomal DNA.
Detailed explanation-4: -Egg and sperm cells have just 23 chromosomes each. That’s half as many chromosomes as regular cells.