Advertisements
Advertisements
प्रश्न
Differentiate between ‘ZZ’ and ‘XY’ type of sex-determination mechanisms.
Advertisements
उत्तर
| ZZ Sex-Determination Mechanism | XY Sex-Determination Mechanism |
| In this type of chromosomal sex determination mechanism, the females are heterogametic, that is, they produce two types of gametes, while the males are homogametic. | In this type of chromosomal sex determination mechanism, the males are heterogametic, that is, they produce two types of gametes, while the females are homogametic. |
| Here, the females produce two types of eggs (A + Z) and (A + W), while the males produce only one type of sperm (A + Z). | Here, the males have an X chromosome and its counterpart Y chromosome, which is distinctly smaller. Hence, the males are XY. However, females have a pair of X chromosomes; therefore, they are XX. |
| Organisms that have the ZZ type of sex-determination mechanism are birds, fishes, some reptiles, etc. | Organisms that have the XY type of sex-determination mechanism are humans and Drosophila. |
संबंधित प्रश्न
A couple with a newborn baby is troubled that the child does not resemble either of them. Suspecting that a mixup occurred at the hospital, they check the blood type of the infant. It is type O. Because the father is type A and the mother type B, they conclude that a mixup has definitely occurred. Are they correct? Give reason for your answer.
Why did T. H. Morgan select Drosophila melanogaster to study sex linked genes for his lab experiments ?
What is heterogamety ? Explain the mechanism of sex determinatin in Drosophila.
Choose the correct answer:
Males have more chances of suffering from sex-linked disease because of ___________
Choose the correct answer:
A single recessive trait, able to express must be on _________
Complete the following sentence with appropriate word:
___________ chromosomes do not take part in sex determination.
How drones are produced in honey bees?
What is haplodiploidy?
Brief about female heterogamety.
Explain the mode of sex determination in honeybees.
How is sex determined in human beings?
Identify the female heterogamety from the chromosomal complements given below.
The maleness of a child is determined by ______
Female heterogamy is shown by
Name the two types of gametes produced by men.
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.
A zygote which has Y chromosome inherited from the father will develop into a ______.
In the XX–XY sex determination system, if a female (XX) is fertilized by an X-bearing sperm, what is the resulting genotype of the offspring?
