Question

1.A scientist is studying a human disorder that may be attributable to a mutation in the mitochondrial DNA. Based on what evidence the scientist believes this

A. Specific genetic mutation is observed
B. A rare parasitic disease is associated with his disorder

C. Maternal rather than Mendelian inheritance pattern is observed

D. The ATP production is affected

2.Eukaryotic and bacterial DNA replication share many features, but eukaryotic DNA replication is more complex. What features of eukaryotic DNA replication are not shared with bacteria?

A.Linear chromosomes

B. All answers are correct

C. DNA complexed with nucleosomes

D. Eukaryotic chromosomes contain multiple ORIs

3. Bacterial transformation involves DNA transfer to a recipient cell

A.By sexual reproduction

B.As naked DNA in solution

C.By cell-to-cell contact

D.By a bacteriophage

4. Mutations in the mitochondrial DNA can cause human disorders. What future approach involving nuclear transplantation might be available to treat mtDNA-based human disorders?

A.Mitochondrial swapping

B.Nuclear disintegration

C.Mitochondrial suppression

D.Nuclear Activation

5. During DNA replication

A. The two DNA strands separate, each strand then becomes a template for the assembly of a similar strand. Each new DNA helix has one old strand with one new strand.

B. The two DNA strands separate, each strand then becomes a template for the assembly of a similar strand. Each new DNA helix has two new strands.

C. The two DNA strands separate, each strand then becomes a template for the assembly of a complementary strand. Each new DNA helix has one old strand with one new strand.

D. The two DNA strands separate, each strand then becomes a template for the assembly of an identical strand. Each new DNA helix has one old strand with one new strand.

6. What is the function of RNA primase in DNA replication?

A.Provides a DNA primer
B. synthesizes RNA primer that provides a free 5′-OH upon which DNA polymerization depends

C. provides a free 3′-OH upon which DNA polymerization depends

D.

provides a free 5′-OH upon which DNA polymerization depends

Answer 1

Answer-

According to the given question-

Question 1- Mitochondrial DNA -are small circular chromosome present in the mitochondria and coded more than 30 genes and passed from the mother to their offspring by the cytoplams of egg cell. Enzymes that are responsible for several pathway occur in mitochondria are synthesized by  mitochondrial DNA.

Maternal inheritance-  are defined as the inheritance of different characters which are transmitted through extranuclear DNA such as mitochondrial DNA from mother to their offspring through their eggs. Mutation in Mitochondrial DNA leads to defects in Mitochondrial DNA ans causes disorder in humans .   Mitochondrial disorders are arises from the nuclear gene disorders because several proteins of mitochondrial metabolism as well as maintenance of  mitochondrial DNA  are coded by the nucleus.so mutation in these genes causes mutation in  mitochondrial DNA ans causes disorders.

So the correct answer for the question is (C) Maternal rather than Mendelian inheritance pattern is observed

Question 2 - DNA Replication is making copy of DNA from DNA double helix with the help of enzyme DNA Polymerases involving several factors responsible for replication. DNA in Eukaryotes are wrapped around histone prortein while prokaryotes doesnot have such features except archea. mostly eukaryotes have linear chromosomes while prokaryotes have circular chromosomes. Eukaryotic DNA replication is complex that the prokaryotes and have multiple origin of replication while prokaryotes have single origin of replication.

So the correct answer for the question Eukaryotic and bacterial DNA replication share many features, but eukaryotic DNA replication is more complex because ( D) Eukaryotic chromosomes contain multiple ORIs.

Question 3- We know that the exchange of genes in bacterial population are through several process such as -

• Conjugation- Transfer of  DNA from the donor cell to recipient bacteria by process of mating.
• Transduction- The DNA is packaged into the bacteriophage which later infect and transfer the DNA into recipient bacteria.
• Transformation- Here the recipient bacteria takes donor DNA from the extracellular medium where the DNA are releases by the Donor bacteria such as naked DNA in solution.

So the correct answer for the question Bacterial transformation involves DNA transfer to a recipient cell is (B).As naked DNA in solution.

Question 4-  Mutations in the mitochondrial DNA are responsible for several disorders and syndrome such as  Kearns–Sayre syndrome, Pearson syndrome, Myopathy,  infantile encephalopathy and diabetes.

.Mitochondrial swapping- It is the swapping of mitochondria in the unfertilized egg where the  germinal vesicle which contains the nuclear chromosomes are transferred to the an oocyte which already have normal mitochondrial DNA whose geminal vesicle is already removed. or by the transfer of ponuclei from the fertilized oocyte where the pronuclei of oocyte have mutated mitochondrial DNA are removed and pronuclei of oocyte having the normal mitochondrial DNA .

.Nuclear disintegration- is the breaking of nucleus into smaller part.

Mitochondrial suppression-   high metabolism rate leads to  high body temperature which was reversed slowly through the Mitochondrial suppression.

Nuclear Activation - is done to restore the function of nucleus.

So the correct answer for the question is  Mutations in the mitochondrial DNA can cause human disorders the approach involving nuclear transplantation might be available to treat mtDNA-based human disorders are (A) Mitochondrial swapping

Question 5- During DNA replication-  (C) The two DNA strands separate, each strand then becomes a template for the assembly of a complementary strand. Each new DNA helix has one old strand with one new strand.

Question 6- RNA primase -a type of RNA polymerase which helps in DNA  replication by synthesizing a primer which is sequence of short RNA and are complementary to the single-stranded DNA template and provides a free 3′-OH upon which DNA polymerization depends.

so the correct answer for the question function of RNA primase in DNA replication is (C) provides a free 3′-OH upon which DNA polymerization depends.