Biology for IGCSE & O level - Inheritance (Section 6)
1
Which of the following processes is directly responsible for creating genetic variation?
Answer
(D)
Crossing over during meiosis
2
What is the role of a promoter region in a gene?
Answer
(B)
To signal the start of transcription.
3
Which of the following is the correct order of events in protein synthesis?
Answer
(B)
Transcription, Translation, Replication
4
What is the expected phenotypic ratio in a monohybrid cross if the alleles show incomplete dominance?
Answer
(B)
1:2:1
5
Which of the following contribute to genetic variation?
Answer
A
B
C
6
What are the products of meiosis II?
Answer
(D)
Four haploid cells
7
What is the term that refers to different forms of a gene?
Answer
(B)
Allele
8
How many chromosomes are typically found in a human somatic (body) cell?
Answer
(B)
46
9
What information can be derived from a pedigree chart?
Answer
A
B
C
10
Which of the following statements is TRUE regarding the products of meiosis?
Answer
(C)
The resulting cells are haploid.
11
Which process results in the separation of homologous chromosomes?
Answer
(B)
Meiosis I
12
During which phase of mitosis does the nuclear envelope reform?
Answer
(D)
Telophase
13
Which of the following statements is true regarding the inheritance of autosomal dominant disorders?
Answer
A
B
D
14
Which of the following is an example of a human trait determined by multiple alleles?
Answer
(A)
Blood type (ABO)
15
What is the significance of the F1 generation in Mendelian genetics?
Answer
(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?
Answer
(C)
Genetic linkage
17
What is the relationship between genotype and phenotype?
Answer
(A)
The genotype determines the phenotype.
18
Which of the following is the primary goal of meiosis?
Answer
(C)
Production of gametes.
19
In a situation of incomplete dominance, what is the phenotype of a heterozygote?
Answer
(C)
It is a blend of the two parental phenotypes.
20
Which of the following are directly involved in protein synthesis?
Answer
A
B
C
21
Which process involves the synthesis of an RNA molecule from a DNA template?
Answer
(C)
Transcription
22
Which type of inheritance is characterized by the interaction between two or more genes to control a single phenotype?
Answer
(B)
Epistasis
23
Which of the following is true about meiosis II?
Answer
(C)
Sister chromatids separate.
24
In a pedigree, what does a filled-in (shaded) symbol represent?
Answer
(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?
Answer
(B)
Transcription
26
Which of the following are events in Meiosis I?
Answer
A
C
D
27
What is the role of a ribosome in protein synthesis?
Answer
(C)
To read the mRNA code and assemble amino acids into a protein.
28
Which processes are involved in sexual reproduction?
Answer
A
B
29
What is the significance of crossing over in meiosis?
Answer
(B)
It increases genetic diversity.
30
If two genes are linked, what does that mean?
Answer
(B)
They are on the same chromosome.
31
What is the purpose of the start codon in translation?
Answer
(B)
To initiate protein synthesis.
32
What is the diploid number for human cells?
Answer
(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?
Answer
(C)
50%
34
If a trait is autosomal dominant, what must the genotype of an affected individual be?
Answer
(D)
Aa or AA
35
What is the function of the anticodon?
Answer
(A)
To bind to the mRNA codon.
36
What is the primary outcome of meiosis?
Answer
(B)
Production of haploid gametes.
37
Which of the following is an example of incomplete dominance?
Answer
(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?
Answer
(A)
Only the dominant phenotype.
39
What does the term 'homozygous recessive' mean?
Answer
(C)
Having two identical recessive alleles for a gene.
40
What is the role of the cell plate in plant cell cytokinesis?
Answer
(A)
To form a new cell wall.
41
During which phase of meiosis does synapsis (pairing of homologous chromosomes) occur?
Answer
(A)
Prophase I
42
In incomplete dominance, what will be the phenotypic ratio of offspring from a cross between two heterozygous individuals?
Answer
(C)
1:2:1
43
What process is represented by the phrase "DNA unwinds and forms a long thread"?
Answer
(D)
Decondensation
44
Which type of cell division produces genetically different cells?
Answer
(C)
Meiosis
45
What is the difference between mitosis and meiosis?
Answer
(C)
Mitosis produces genetically identical cells; meiosis produces genetically different cells.
46
What is the relationship between genes, DNA, and chromosomes?
Answer
(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)
Answer
A
B
D
48
In a situation where codominance is present, what will happen to the phenotype?
Answer
(D)
Both alleles are equally expressed in the phenotype.
49
Which of the following is an example of a phenotype?
Answer
(C)
An organism's observable traits.
50
During what phase of mitosis do the chromosomes line up in the middle of the cell?
