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प्रश्न
Identify chromosomal disorder caused due to non-disjunction of the 21st number of chromosomes and enlist its symptoms.
Identify chromosomal disorder caused due to non-disjunction of 21% chromosome and enlist its characteristics.
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उत्तर
Down syndrome is usually caused by an error in cell division called non-disjunction. Non-disjunction results in an embryo with three copies of chromosome 21 instead of the usual two.
Common Symptoms (Characteristics) of Down syndrome are:
- Mild or moderate mental retardation and poor skeletal development.
- Distinct facial features like small head, ears and mouth.
- Eyes slant up and out with internal epicanthal folds.
संबंधित प्रश्न
Give the importance of heterocyst in cyanobateria.
Very Short Answer Question.
Give an example of a chromosomal disorder caused due to nondisjunction of autosomes.
Identify the option that correctly represents the number of chromosomes in Down syndrome.
Thalassemia and sickle cell anemia are caused due to a problem in globin molecule synthesis. Select the correct statement.
If a colour-blind man marries a woman who is homozygous for normal colour vision, the probability of their son being colour-blind is ______.
A woman with albinic father marries an albinic man. The proportion of her progeny is ______.
In sickle-cell anaemia, shape of RBCs under oxygen tension becomes ______.
Read the following and answer from given below:
Turner's syndrome is an example of monosomy. It is formed by the union of an allosome-free egg and a normal 'X' containing sperm or a normal egg and an allosome-free sperm. The individual has 2n = 45 chromosomes (44 + X0) instead of 46. Such individuals are sterile females who have rudimentary ovaries, underdeveloped breasts, small uterus, short stature, webbed neck, and abnormal intelligence. They may not menstruate or ovulate. This disorder can be treated by giving female sex hormones to women from the age of puberty to make them develop breasts and have menstruation. This makes them feel more normal.
The number of Barr bodies present in a female with Turner's syndrome is ______
Clotting of blood is to ______.
If a father and son are both defective in red-green colour vision, is it likely that the son inherited the trait from his father? Comment.
