GROWTH DEVELOPMENT CHILD
HEREDITY AND ENVIRONMENT
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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12
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26
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46
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33
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Detailed explanation-1: -Humans typically have 23 pairs of chromosomes, or 46 chromosomes in total. Chromosomes are made up of long strands of DNA, which contain all the body’s genes.
Detailed explanation-2: -Human cells normally contain 23 pairs of chromosomes, for a total of 46 chromosomes in each cell .
Detailed explanation-3: -Humans, like many other species, are called ‘diploid’. This is because our chromosomes exist in matching pairs – with one chromosome of each pair being inherited from each biological parent. Every cell in the human body contains 23 pairs of such chromosomes; our diploid number is therefore 46, our ‘haploid’ number 23.
Detailed explanation-4: -Females have two X chromosomes, while males have one X and one Y chromosome. A picture of all 46 chromosomes in their pairs is called a karyotype. A normal female karyotype is written 46, XX, and a normal male karyotype is written 46, XY.
Detailed explanation-5: -In meiosis, a cell containing the diploid number of chromosomes is converted into four cells, each having the haploid number of chromosomes. In human cells undergoing meiosis, for instance, a cell containing 46 chromosomes yields four cells, each with 23 chromosomes.