Biology
Grade-9
Easy
Question
Which of the following genetic disorder is caused due to the presence of an additional chromosome 21?
- Down’s syndrome
- Turner’s Syndrome
- Turner’s Syndrome
- Fragile X syndrome
Hint:
Down's syndrome
The correct answer is: Down’s syndrome
Most cases of Down syndrome result from trisomy 21, which means each cell in the body has three copies of chromosome 21 instead of the usual two copies.
Researchers believe that having extra copies of genes on chromosome 21 disrupts the course of normal development, causing the characteristic features of Down syndrome and the increased risk of health problems associated with this condition.
Related Questions to study
Biology
If a human cell is identified to have X and Y chromosomes, the person is regarded as __________
If a human cell is identified to have X and Y chromosomes, the person is regarded as __________
BiologyGrade-9
Biology
In a human cell, each chromosome possesses two identical _______
In a human cell, each chromosome possesses two identical _______
BiologyGrade-9
Biology
A normal human cell has _____________ sex chromosomes
A normal human cell has _____________ sex chromosomes
BiologyGrade-9
Biology
Which of the following structural feature is present at the end portion of a chromosome?
Which of the following structural feature is present at the end portion of a chromosome?
BiologyGrade-9
Biology
Which of the following experimental technique is used to identify genetic disorders?
Which of the following experimental technique is used to identify genetic disorders?
BiologyGrade-9
Biology
Which of the following statement is incorrect?
Which of the following statement is incorrect?
BiologyGrade-9
Biology
The diagrammatic representation of karyotype of a species is known as __________
The diagrammatic representation of karyotype of a species is known as __________
BiologyGrade-9
Biology
How many autosomes are present in a normal human cell?
How many autosomes are present in a normal human cell?
BiologyGrade-9
Biology
Identify the correct statement
Identify the correct statement
BiologyGrade-9
Biology
If two interacting alleles are present on the same gene locus then it is called non-allelic gene interactions.
If two interacting alleles are present on the same gene locus then it is called non-allelic gene interactions.
BiologyGrade-10
Biology
Epistasis is an example of inter-genic gene interactions.
Epistasis is an example of inter-genic gene interactions.
BiologyGrade-10
Biology
Multiple alleles help is producing variation.
Multiple alleles help is producing variation.
BiologyGrade-10
Biology
The alleles in the ABO blood group system gives rise to __________ genotypes.
The alleles in the ABO blood group system gives rise to __________ genotypes.
BiologyGrade-10
Biology
Which of the following is NOT an example of inter-genic gene interactions?
Which of the following is NOT an example of inter-genic gene interactions?
BiologyGrade-10
Biology
This type of inheritance pattern is called:
This type of inheritance pattern is called:
BiologyGrade-10