Biology for IGCSE & O level - Inheritance (Section 6)
1
Which of the following processes is directly responsible for creating genetic variation?
отговор
(D)
Crossing over during meiosis
2
What is the role of a promoter region in a gene?
отговор
(B)
To signal the start of transcription.
3
Which of the following is the correct order of events in protein synthesis?
отговор
(B)
Transcription, Translation, Replication
4
What is the expected phenotypic ratio in a monohybrid cross if the alleles show incomplete dominance?
отговор
(B)
1:2:1
5
Which of the following contribute to genetic variation?
отговор
A
B
C
6
What are the products of meiosis II?
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(D)
Four haploid cells
7
What is the term that refers to different forms of a gene?
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(B)
Allele
8
How many chromosomes are typically found in a human somatic (body) cell?
отговор
(B)
46
9
What information can be derived from a pedigree chart?
отговор
A
B
C
10
Which of the following statements is TRUE regarding the products of meiosis?
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(C)
The resulting cells are haploid.
11
Which process results in the separation of homologous chromosomes?
отговор
(B)
Meiosis I
12
During which phase of mitosis does the nuclear envelope reform?
отговор
(D)
Telophase
13
Which of the following statements is true regarding the inheritance of autosomal dominant disorders?
отговор
A
B
D
14
Which of the following is an example of a human trait determined by multiple alleles?
отговор
(A)
Blood type (ABO)
15
What is the significance of the F1 generation in Mendelian genetics?
отговор
(B)
It is the result of crossing the P generation.
16
If two genes are located very close together on the same chromosome, what is more likely to happen?
отговор
(C)
Genetic linkage
17
What is the relationship between genotype and phenotype?
отговор
(A)
The genotype determines the phenotype.
18
Which of the following is the primary goal of meiosis?
отговор
(C)
Production of gametes.
19
In a situation of incomplete dominance, what is the phenotype of a heterozygote?
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(C)
It is a blend of the two parental phenotypes.
20
Which of the following are directly involved in protein synthesis?
отговор
A
B
C
21
Which process involves the synthesis of an RNA molecule from a DNA template?
отговор
(C)
Transcription
22
Which type of inheritance is characterized by the interaction between two or more genes to control a single phenotype?
отговор
(B)
Epistasis
23
Which of the following is true about meiosis II?
отговор
(C)
Sister chromatids separate.
24
In a pedigree, what does a filled-in (shaded) symbol represent?
отговор
(C)
An individual expressing the trait
25
What is the name of the process where a strand of DNA is used to make a complementary RNA molecule?
отговор
(B)
Transcription
26
Which of the following are events in Meiosis I?
отговор
A
C
D
27
What is the role of a ribosome in protein synthesis?
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(C)
To read the mRNA code and assemble amino acids into a protein.
28
Which processes are involved in sexual reproduction?
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A
B
29
What is the significance of crossing over in meiosis?
отговор
(B)
It increases genetic diversity.
30
If two genes are linked, what does that mean?
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(B)
They are on the same chromosome.
31
What is the purpose of the start codon in translation?
отговор
(B)
To initiate protein synthesis.
32
What is the diploid number for human cells?
отговор
(B)
46
33
If a woman is a carrier for an X-linked recessive trait, and her husband does NOT have the trait, what is the probability their daughter will also be a carrier?
отговор
(C)
50%
34
If a trait is autosomal dominant, what must the genotype of an affected individual be?
отговор
(D)
Aa or AA
35
What is the function of the anticodon?
отговор
(A)
To bind to the mRNA codon.
36
What is the primary outcome of meiosis?
отговор
(B)
Production of haploid gametes.
37
Which of the following is an example of incomplete dominance?
отговор
(B)
Flower color in snapdragons (red x white = pink).
38
What are the possible phenotypes resulting from a cross between a homozygous dominant and a heterozygous individual, assuming complete dominance?
отговор
(A)
Only the dominant phenotype.
39
What does the term 'homozygous recessive' mean?
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(C)
Having two identical recessive alleles for a gene.
40
What is the role of the cell plate in plant cell cytokinesis?
отговор
(A)
To form a new cell wall.
41
During which phase of meiosis does synapsis (pairing of homologous chromosomes) occur?
отговор
(A)
Prophase I
42
In incomplete dominance, what will be the phenotypic ratio of offspring from a cross between two heterozygous individuals?
отговор
(C)
1:2:1
43
What process is represented by the phrase "DNA unwinds and forms a long thread"?
отговор
(D)
Decondensation
44
Which type of cell division produces genetically different cells?
отговор
(C)
Meiosis
45
What is the difference between mitosis and meiosis?
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(C)
Mitosis produces genetically identical cells; meiosis produces genetically different cells.
46
What is the relationship between genes, DNA, and chromosomes?
отговор
(B)
Chromosomes are made of genes, which are made of DNA.
47
Which of the following are events that occur during translation? (Select all that apply)
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A
B
D
48
In a situation where codominance is present, what will happen to the phenotype?
отговор
(D)
Both alleles are equally expressed in the phenotype.
49
Which of the following is an example of a phenotype?
отговор
(C)
An organism's observable traits.
50
During what phase of mitosis do the chromosomes line up in the middle of the cell?
