Carriers vs Affected Individuals

Q. It is well known that Queen Victoria of England was a carrier for haemophilia. She married an unaffected male and since this is an X-linked disease, it can be predicted that

1. all her sons had the disease
2. all her daughters had the disease
3. both her parents had the disease
4. haemophilia would have occurred more in her male descendants than her female descendants

Q. (I) Pleiotropic genes have multiple phenotypic effects
(II) Multiple alleles exhibit the same phenotypic expression
(III) Cystic fibrosis and phenylketonuria are examples of pleiotropism

1. Statement I and II are correct while statement III is incorrect
2. Statement I and III are correct while statement II is incorrect
3. Statement II and III are correct while statement I is incorrect
4. All three statements are correct

Q. A normal couple has their first child, who is haemophilic. Work out a cross to show how it is possible. State the possibility of the normal and the haemophilic children, along with their sexes, that can be born to them. [3 marks]

Q. Represented below is the inheritance pattern of a certain type of trait in humans. Which of the following could be an example for this type of inheritance?

1. Colour blindness
2. Sickle cell anaemia
3. Phenylketonuria
4. Thalassemia

Q. A Y-linked gene is responsible for hypertrichosis (long hair on ears). When an affected man marries a normal woman, what percentage of their daughters would be expected to have hairy ears?

1. 1%
2. 100%
3. 0%
4. 50%

Q.
This pedigree shows inheritance of which condition?

1. Colour blindness
2. Phenylketonuria
3. Hemophilia
4. Down's syndrome

Q. What is pleiotropy?

Q.

In diseases that show X-linked inheritance, the females are usually the ______.

1. Promoters

2. Carriers

3. Operators

4. None of the above

Q. Which among the following is called a Royal disease?

Q.

X-linked disorders are called as royal diseases since they were prevalent in the Royal Family of England.

1. True

2. False

Q. Colour blindness is found more in males than in females because of which of the following reasons?

1. The males containing the single affected X chromosome are colour blind.
2. Males having affected Y chromosome are colour blind.
3. Heterozygous females are colour blind.
4. Affected X chromosome has much high affinity to Y chromosome as compared to unaffected X chromosome.

Q. Can you alter the rate of growth in an organism? If yes how?

Q. Following are the two statements given.

I. If both father and son are colour blind, it is definite that the son inherited the trait from his father.
II. Colour blindness is more common in males than females.

Select the correct alternative.

1. Both I and II are true
2. I is true, II is false
3. I is false, II is true
4. Both I and II are false

Q. Which of these is not a Mendelian disorder?

1. Cystic fibrosis
2. Sickle-cell anaemia
3. Colour blindness
4. Turner’s syndrome

Q. Which of these is not a Mendelian disorder?

1. Cystic fibrosis
2. Sickle-cell anaemia
3. Colour blindness
4. Turner’s syndrome

Q. Assertion :Turners syndrome caused due to absence of any one of the X and Y sex chromosome. Reason: Such individuals show masculine as well as feminine development.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q.

In diseases that show X-linked inheritance, the females are usually the ______.

1. Promoters

2. Carriers

3. Operators

4. None of the above

Q.

In diseases that show X-linked inheritance, the females are usually the ______.

1. Promoters

2. Carriers

3. Operators

4. None of the above

Q.

X-linked disorders are called as royal diseases since they were prevalent in the Royal Family of England.

1. True

2. False

Q.

X-linked disorders are called as royal diseases since they were prevalent in the Royal Family of England.

1. True

2. False

Q. Answer in 40 to 80 words:
Write the karyotype of the following syndromes:
i) Down's syndrome
ii) Kinefelter's syndrome
iii) Turner's syndrome

Q. A child suffering from thalassemia is born to a normal couple. But the mother is being blamed by the family for delivering a sick baby.
(a) What is thalassemia?
(b) How would you counsel the family not to blame the mother for delivering a child suffering from this disease? Explain.
(c) List the values your counselling can propagate in the families.

Q. Pleiotropic effect is found in

1. Scurvy
2. Night blindness
3. Haemophilia
4. Sickle cell anaemia

Q. Myotonic dystrophy is an example of

1. Autosomal recessive trait
2. Autosomal dominant trait
3. Sex linked recessive trait
4. Sex linked dominant trait

Q. The condition in which a pair of chromosomes carry similar alleles of a particular character is known as _______.

Q. A normal couple give birth to haemophilia son and two normal doughter work out the cross to show the genotype of the parents and there progeny
2. Give the possible genotype of parents who can give birth to haemophilia doughter

Q.

what is the probability of a male child being haemophilic , if his mother is a carrier of the disease and his father is a normal person?

Q. A hereditary disease which is never passed on from father to son is

1. Autosomal linked disease
2. X-chromosomal linked disease
3. Y-chromosomal linked disease
4. None of the above

Q. Which of the following disease, has a XXY chromosome constitution?

1. Turner's syndrome
2. Down's syndrome
3. Patau's syndrome
4. Klinefelter's syndrome

Q. A woman expresses an X-linked recessive disorder. Select the correct statemet about woman parents?
I. Her mother passed on an allele for the disorder
II. Her father expresses the same disorder
III. Her mother does not express the disorder

1. I only
2. II only
3. I and II only
4. II and III only
5. I, II, and III