Cell Cycle Control

Q. Discuss the process of translation in detail.

Q. During which phase(s) of the cell cycle, the amount of DNA in a cell remains at the 4C level if the initial amount is denoted as 2C?

1. Only $G_2$
2. $G_0$ and $G_1$
3. $G_1$ and S
4. $G_2$ and M

Q. Briefly discuss the importance of chromosomes in an organism.

Q. Read statements a—d.
(a) In transcription, adenine pairs with uracil
(b) Regulation of lac operon by repressor is positive regulation
(c) Human genome has approximately $50,000$ genes
(d) Haemophilia is sex-linked recessive disease
How many of the above statements are correct?

1. $3$
2. $2$
3. $4$
4. $2$

Q. Which one of the following is wrongly matched?

1. Operon—Structural genes, operator and promoter
2. Repressor protein—Binds to operator to stop enzyme synthesis
3. Transcription—Writing information from DNA to proteins
4. Translation—Using information in mRNA to make protein

Q.

What is the significance of the $G_0$ phase?

Q. With regard to mature mRNA in eukaryotes:

1. introns appear but exons do not appear in the mature RNA
2. exons and introns do not appear in the mature RNA
3. both exons and introns appear in the mature RNA
4. exons appear but introns do not appear in the mature RNA

Q. What is referred to as satellite chromosome?

Q. In the vector pBR322, restriction site of Pvu II is present in

1. $am{p}^R$
2. $te{t}^R$
3. $rop$
4. $ori$

Q. A phase of the cell cycle which lasts more than 95% of the total duration is

1. prophase
2. interphase
3. anaphase
4. telophase

Q. Which is not part of transcription unit?

1. Promoter
2. Terminator
3. Inducer
4. Structural gene

Q. Smallest gene affected by mutation is

1. 
   Recon
2. 
   Muton
3. 
   Cistron
4. 
   Exon

Q.

What are 2 examples of external factors that influence the cell cycle?

Q. In $lac$ operon, ‘inducer lactose’ serves as an enzyme-substrate for the enzyme

1. Permease
2. ꞵ-galactosidase
3. Endonuclease
4. Transacetylase

Q.

What are chromosomes? What are they made of?

Q.

Which of these best describes the role and mechanism of action of Cyclin-dependent kinases (CDKs) in the cell cycle?

1. Directing a cell to undergo apoptosis

2. Phosphorylation of cyclin and in turn downstream targets

3. All of the above

4. Ensuring the accuracy of DNA replication and checking for damages

Q. Cells which are not dividing are likely to be at

1. G${}_1$
2. G${}_2$
3. G${}_0$
4. S phase

Q.

Which of these best describes the role and mechanism of action of Cyclin-dependent kinases (CDKs) in the cell cycle?

1. CDKs bind to cyclin, the formed complex is in an activated state.

2. Cyclins are a family of proteins that control the progression of cells through the cell cycle

3. Through phosphorylation, CDKs signal the cell that it is ready to pass into the next stage of the cell cycle.

4. All of the above

Q. Which of the following does not happen in G${}_1$ phase?

1. Cell organelles duplication
2. DNA replication
3. Cytoplasmic growth
4. RNA synthesis

Q.

Chromosomes bear hereditary units known as __________.

Q.

Give appropriate terms for the following (iv) Long thread-like structures in a cell that contain genes.

Q. ADA deficiency is caused due to the

1. Inversion
2. Translocation
3. Substitution
4. Deletion

Q. To initiate translation, the mRNA first binds to:

1. The large ribosomal subunit
2. The whole ribosome
3. No such specificity exists
4. The small ribosomal subunit

Q. What would be the number of chromosomes in the aleurone layer if the megaspore mother cell contains 10 chromosomes?

1. b. 20
2. c. 15
3. a. 10
4. d. 30

Q.

Given below are groups of terms. In each group the first pair indicates the relationship between the two terms.

Rewrite and complete the second pair on a similar basis.

Example : Oxygen : Inspiration : : Carbon dioxide : Expiration

Cytoplasm : Cytokinesis:: Nucleus :

Q. What is the correct gene expression pathway?

1. Gene―transcription―mRNA―translation―protein
2. Gene―translation―mRNA―transcription―protein
3. Transcription―gene―translation―mRNA―protein
4. Gene―mRNA

Q.

Name the following

The thread like structure that is formed by condensation of chromatin during cell division.

Q.

Which of these would be required for the regulation of cell cycle ?

1. Cyclin-CDK Complex

2. Phosphorylated CDK

3. CDK

4. Cyclin

Q. Splicing is meant for eliminating

1. Mutons
2. Introns
3. Exons
4. Recons

Q. Which of the following is required as inducer(s) for the expression of $lac$ operon?

1. Lactose
2. Galactose
3. Glucose
4. Lactose and galactose