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Question
The two versions of a trait (character) which are brought in by the male and female gametes are situated on
Options
copies of the same chromosome
two different chromosomes
sex chromosomes
any chromosome
Solution
copies of the same chromosome
Explanation -
An organism inherits two copies of each chromosome, one each from the male and female parents. The two forms of a gene controlling a character (two versions of a trait) are present at the same location on the two copies of one of the chromosomes. At the time of gamete formation, when a chromosome pair segregate and move to different gametes, two forms of a gene also segregate, each gamete receiving one copy of a chromosome along with one form of a gene. When these gametes from two parents fuse, the two copies of the same chromosome along with the two forms of a gene are also brought together in the organism of the next generation.
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RELATED QUESTIONS
Write notes on sex determination in the unborn baby.
Does genetic combination of mother play a significant role in determining the sex of a new born baby?
The sex of a child is determined by which of the following?
(a) the length of the mother's pregnancy
(b) the length of time between ovulation and copulation
(c) the presence of and X chromosome in an ovum
(d) the presence of a Y chromosome in a sperm
In which livings, female decides the sex? Give two examples.
Give Technical Term:
The cell which determines the sex of a baby.
Diploid larvae which get royal jelly as food develops into ____________ and other develops into workers (sterile females).
The ‘X’ body of Henking was observed in ______.
Grasshopper is an example of XO type of sex determination in which the males have ______.
Sex of an individual is determined by different factors in various species. Some animals rely entirely on the environmental ones, while in some other animals the individuals can change their sex during their life time indicating that sex of some species is not genetically determined. However in human beings, the sex of an individual is largely determined genetically.
- In what way are the sex chromosomes 'X' and 'Y' different in size? Name the mismatched pair of sex chromosome in humans.
- Write the number of pair/pairs of sex chromosomes present in human beings. In which one of the parent (male/female) perfect pair/pairs of sex chromosome are present?
- Citing two examples, justify the statement "Sex of an individual is not always determined genetically".
OR
Draw a flow chart to show that sex is determined genetically in human beings.
All human chromosomes ate not paired. Most human chromosomes have a maternal and a paternal copy, and we have 22 such pairs. But one pair called the sex chromosomes, is odd in not always being a perfect pair. Women have a perfect pair of sex chromosomes. But men have a mismatched pair in which one is normal sized while the other is a short one.
(a) In humans, how many chromosomes are present in a Zygote and in each gamete?
(b) A few reptiles rely entirely on environmental cues for sex determination. Comment.
(c) "The sex of a child is a matter of chance and none of the parents are considered to be responsible for it." Justify it through flow chart only.
OR
(c) Why do all the gametes formed in human females have an X chromosome?
