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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 an example of a human disorder that is caused due to a single gene mutation.
A couple with normal vision bear a colour blind child. Work out a cross to show how it is possible and mention the sex of the affected child.
In human beings 45 chromosomes/single X/XO abnormality causes ______.
Mention the symptoms of Phenylketonuria.
Read the following statements and select the correct option.
i. Genetic disorders are broadly categorised as, Mendelian disorders and chromosomal disorders.
ii. Mendelian disorders are caused due to absence or excess of one or more chromosomes or their abnormal arrangement.
iii. Chromosomal disorders are mainly caused due to alteration or mutation in the gene.
In sickle-cell anaemia, shape of RBCs under oxygen tension becomes ______.
Rajesh and Mahesh have defective haemoglobin due to genetic disorders. Rajesh has too few globin molecules while Mahesh has incorrectly functioning globin molecules. Identify the disorder they are suffering from.
| Rajesh | Mahesh | |
| A. | Sickle cell anaemia - an autosome linked recessive trait | Thalassemia - an autosome linked dominant trait |
| B. | Thalassemia - an autosome linked recessive blood disorder | Sickle cell anaemia - an autosome linked recessive trait |
| C. | Sickle cell anemia - an autosome linked recessive trait | Thalassemia - an autosome linked recessive blood disorder |
| D. | Thalassemia - an autosome linked recessive blood disorder | Sickle cell anaemia - an autosome linked dominant trait |
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.
Turner's syndrome is a/an ______
Which of the following is called as Royal disease?
Which of the folowing is a correct match?
