In a typical dihybrid cross \(A a B b \times A a B b\) [symbols have usual meanings; assume independent assortment], what proportion of progeny are expected to carry both dominant alleles?
1. ¼
2. 9/16
3. 3/16
4. ½

Subtopic:  Dihybrid Cross Analysis |
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Consider the given two statements:
Statement I:  Genes are the units of inheritance and contain the information that is required
to express a particular trait in an organism.
Statement II:  Genes which code for a pair of contrasting traits are known as alleles, i.e.,
they are slightly different forms of the same gene
 
1.  Statement I is correct; Statement II is incorrect
2.  Statement I is correct; Statement II is correct
3.  Statement I is incorrect; Statement II is correct
4.  Statement I is incorrect; Statement II is incorrect
Subtopic:  Monohybrid Cross: Further Understanding |
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Identify the incorrect statement:
1. Mendel found the phenotype of the F1 heterozygote Tt to be exactly like the TT parent in appearance.
2. He proposed that in a pair of dissimilar factors, one dominates the other.
3. It is convenient (and logical) to use the capital and lower case of an alphabetical symbol to remember this concept of dominance and recessiveness.
4. It is convenient (and logical) to use the capital and lower case of different alphabets symbol to remember this concept of dominance and recessiveness.
Subtopic:  Monohybrid Cross: Further Understanding |
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A typical dihybrid cross results in the formation of 500 F2 progeny. What is the expected number of recombinants among these progeny?
1. 280
2. 31
3. 94
4. 187
Subtopic:  Dihybrid Cross Analysis |
 63%
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In a monohybrid cross, ¼ of the random fertilisations lead to:
I: Homozygous dominant progeny
II: Homozygous recessive progeny
III: Heterozygous progeny
1. Only I and II are correct
2. Only I and III are correct
3. Only II and III are correct
4. I, II and III are correct
Subtopic:  Monohybrid Cross: Further Understanding |
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Consider the given two statements:
Assertion (A):  Mendel self-pollinated the F2 plants and found that dwarf F2
plants continued to generate dwarf plants in F3 and F4 generations.
 
Reason (R):  The genotype of the dwarfs was homozygous.
 
1.  Both (A) and (R) are True but (R) does not correctly explain (A).
2.  Both (A) and (R) are True and (R) correctly explains Assertion.
3.  Both (A) and (R) are False.
4.  (A) is True but (R) is False.
Subtopic:  Monohybrid Cross: Further Understanding |
 61%
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In Antirrhinum majus, how many of the given cross will produce all progeny exhibiting similar phenotypes [symbols carry usual meanings]?
I: \(Rr \times Rr\)
II: \(Rr \times rr\)
III: \(RR \times rr\)
IV: \(Rr \times RR\)
1. 1
2. 2
3. 3
4. 4
Subtopic:  Monohybrid Cross: Further Understanding |
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Consider the given two statements:
Assertion:    Female must have the colour blindness gene on both of their X chromosomes to be colour blind.
Reason:   Colour blindness is a sex linked dominant trait.
 
1.  Both Assertion and Reason are true but the Reason does not correctly explain the Assertion.
2.  Both Assertion and Reason are true and the Reason correctly explains the Assertion.
3.  Assertion is false and Reason is also false.
4.  Assertion is true but Reason is false.
Subtopic:  Pedigree Analysis: More Examples |
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Genes that are located on the same chromosome are called as:
1. Duplicate genes
2. Pseudo genes
3. Linked genes
4. Codominant genes
Subtopic:  Understanding Linkage |
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The karyotype shown below is of a person affected with:

1. Klinefelter’s syndrome
2. Turner’s syndrome
3. Down’s syndrome
4. Edward’s syndrome
Subtopic:  Sex Aneuploidy - Turner & Klinefelter Syndrome |
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