MCQ’S ON REGULATIONS OF GENE EXPRESSION IN EUKARYOTES
1. Eukaryotic entities
(a) in the presence of a cAMP molecule, it carries out protein synthesis
(b) have only operons assisting in gene expression
(c) transcription takes place in the nucleus and translation in the cytoplasm
(d) transcription occurs in the cytoplasm and translation in nucleus
Answer: (c)
2. A genomic DNA possesses functioning units, a group of genes under the influence of promoters known as
(a) genes
(b) operons
(c) anticodon
(d) codon
Answer: (b)
3. All regulatory proteins possess a common DNA binding motif that is specific flexes in their protein chains permitting them to interlock with
(a) the outside groove of DNA helix
(b) the major groove of DNA helix
(c) the minor groove of DNA helix
(d) the inner groove of DNA helix
Answer: (b)
4. Regulatory proteins turn transcription off through binding to a site rapidly at the front of the promoter and many times even overlaps the promoter, this site is the
(a) regulatory site
(b) operator site
(c) suppressor site
(d) transcriptional control site
Answer: (b)
5. Seemingly, the vertebrate cells contain a protein which binds to clusters of 5-methylcytosine ensuring that the bound gene stays in the “off” position. This regulation on the role of gene regulation is an outcome of
(a) Methylation
(b) Translation
(c) Enhancer expression
(d) operator suppression
Answer: (a)
6. The transcriptional gene control in eukaryotes is mediated by
(a) metabolites that bind to the cis-acting elements
(b) trans-acting factors failing to bind to cis-acting elements
(c) trans-acting factors binding to cis-acting elements
(d) repressor proteins that bind to operator sites
Answer: (c)
7. Basic tools of genetic regulation are the ability of some proteins to bind to specific
(a) regulatory DNA sequences
(b) regulatory RNA sequences
(c) enzymes of cells
(d) promoter portions of genes
Answer: (a)
8. In the regulation of gene expression, this is an incorrect statement
(a) in the bacteria, it permits to replicate with no control
(b) in the bacteria, it permits to adapt to changing environments
(c) permits the maintenance of homeostasis in multicellular entities
(d) permits the functioning of multicellular entities on the whole
Answer: (a)
9. There are these many histones in the core of a nucleosome
(a) 8
(b) 6
(c) 4
(d) 2
Answer: (a)
10. In eukaryotes and bacteria, the most common form of regulation is
(a) promoter control
(b) translation control
(c) repressor control
(d) transcriptional control
Answer: (d)
MCQ’S ON HARDY WEINBERG LAW
1. In the Caucasian population of the US, 1 in 2500 babies is affected by a recessive condition – cystic fibrosis. In this population, the frequency of the dominant allele is
(a) 0.02
(b) 0.36
(c) 0.56
(d) 0.98
Answer: (d)
2. A sampled “a” population has 36% of homozygous recessive genotype (aa). Then the frequency of allele “a” is
(a) 0%
(b) 20%
(c) 60%
(d) 70%
Answer: (c)
3. 360 out of 1000 individuals in a population have a genotype of AA while 480 have Aa genotype. The rest 160 belong to aa. Frequency of allele A in this population is
(a) 0.7
(b) 0.6
(c) 0.5
(d) 0.4
Answer: (b)
4. A gene locus has two alleles A and a. If the frequency of dominant allele A is 0.4, then the frequency of homozygous dominant, heterozygous and homozygous recessive individuals in the population is
(a) 0.16(AA); 0.48(Aa); 0.36(aa)
(b) 0.16(AA); 0.24(Aa); 0.36(aa)
(c) 0.16(AA); 0.36(Aa); 0.48(aa)
(d) 0.36(AA); 0.48(Aa); 0.16(aa)
Answer: (a)
5. What does p2 in the below mentioned Hardy-Weinberg equation indicate?
(p+q)2 = p2 + 2pq + q2
(a) individuals that are heterozygous dominant
(b) individuals having a lethal allele
(c) individuals that are homozygous dominant
(d) individuals that are homozygous recessive
Answer: (c)
6. 25 individuals in a population are homozygous dominant, then the individuals that are expected to be homozygous recessive are
(a) 100
(b) 75
(c) 50
(d) 25
Answer: (d)
7. Consider a population of sheep to be in Hardy-Weinberg equilibrium. The allele for black wool(w) has an allele frequency of 0.81 while the allele for white wool(W) has an allele frequency of 0.19. Then the percentage of heterozygous individuals in the population is
(a) 4%
(b) 15%
(c) 31%
(d) 66%
Answer: (c)
8. This condition is essential for a population to be in the Hardy-Weinberg equilibrium
(a) random mating
(b) no mutations
(c) large population
(d) all of these
Answer: (d)
9. This statement describes the Hardy-Weinberg law the best
(a) it is impossible to predict expected allele frequencies mathematically
(b) in large populations, dominant alleles become more prevalent
(c) allele frequency changes over a period of time in a large population
(d) mechanism of inheritance in a large population does not change allele frequency
Answer: (d)
10. This is true of the population which are included in Hardy-Weinberg equilibrium
(a) entities migrate constantly
(b) populations should be limited and small
(c) mating is random
(d) process of natural selection is occurring
Answer: (c)
11. Hardy-Weinberg equilibrium operates in the absence of
(a) Gene flow
(b) Mutation
(c) Natural selection
(d) All of these
Answer: (d)
