Microtubules

Q. What is the role of the spindle fibers during mitosis?

1. They help to separate the chromosomes
2. They break down the nuclear membrane
3. They help in the duplication of the DNA
4. They make the chromosomes visible

Q.

Where are kinetochores located?

Q.

Microfilaments are composed mainly of a protein called

1. Chitin

2. Myosin

3. Tubulin

4. Actin

Q. Drugs such as vincristine and colchicine disrupt mitosis by binding to tubulin and interferes with microtubule assembly and disassembly. Exactly what mitotic structure do these drugs target and what effect would that have on cell division?

1. The drugs bind tubulin and inhibit the formation of spindle. This can arrest the cell cycle.
2. The drugs bind the spindle fiber and hinder the separation of chromatins. This promotes the division spontaneously.
3. The drugs bind the tubulin, thereby inhibiting their division in S phase. This inhibits cell division.
4. The drugs bind the tubulin, which leads to an error in the chromosome separation. This could lead to apoptosis.

Q.

State whether the following statements are true or false. If false, rewrite the correct form of the statement by changing the first and last word only:

Centromere is the organelle of the cell that initiates cell division.

1. True
2. False

Q. Which biomolecules are spindle fibres composed of?

1. Lipid
2. Protein
3. Carbohydrate
4. Nucleic acid

Q. Which one is resistant to enzyme action?

1. Wood fibre
   
2. Cork
   
3. Leaf cuticle
   
4. Pollen exine
   

Q. Which of the following statements is incorrect for centrioles?

1. Both the centrioles in a centrosome lie perpendicular to each other
2. Central proteinaceous hub is missing in a centriole
3. Each centriole has an organisation like that of a cartwheel
4. Centrosome usually contains 2 cylindrical centrioles

Q. Cyanogen bromide is employed in

1. Genetic fingerprinting
2. Tissue culture
3. Hybridoma technology
4. Synthesis of humulin

Q.

Protein subunit found within microtubules is:

1. Collagen

2. Tubulin

3. Myosin

4. DNA

Q. Microtubules are the constituents of:

1. Spindle fibres, centrioles and cilia
2. Centrioles, spindle fibres and chromatin
3. Cilia, Flagella and Peroxisomes
4. Centrosome, Nucleosome and Centrioles

Q. Drugs such as vincristine and colchicine disrupt mitosis by binding to tubulin and interferes with microtubule assembly and disassembly. Exactly what mitotic structure do these drugs target and what effect would that have on cell division?

1. The drugs bind the spindle fiber and hinder the separation of chromatins. This promotes the division spontaneously.
2. The drugs bind the tubulin, thereby inhibiting their division in S phase. This inhibits cell division.
3. The drugs bind the tubulin, which leads to an error in the chromosome separation. This could lead to apoptosis.
4. The drugs bind tubulin and inhibit the formation of spindle. This can arrest the cell cycle.

Q. Which one of the following cellular parts is correctly described?

1. Centrioles - sites for active RNA synthesis.
2. Ribosomes - those on chloroplasts are larger (80S) while those in the cytoplasm are smaller (70S).
3. Lysosomes- optically active at a pH of about 8.5
4. Thylakoids - flattened membranous sacs forming the grana of chloroplasts.

Q.

What is the hub in centrioles connected with?

Q.

What does the mitotic spindle depend on?

Q. What is the role of the spindle fibers during mitosis?

1. They help to separate the chromosomes
2. They break down the nuclear membrane
3. They help in the duplication of the DNA
4. They make the chromosomes visible

Q. Spindle fibre attaches onto:

1. Telomere of the chromosome
2. Kinetochore of the chromosome
3. Centromere of the chromosome
4. Kinetosome of the chromosome

Q. Spindle fibres are made up of

1. Proteins
2. Cellulose
3. Lipids
4. Pectin

Q. Which of the following is used as the mitotic spindle poison?

1. $C{a}^{+}$
2. $M{g}^{+}$
3. Tubulin
4. Colchicine

Q. Spindle fibre is made of

1. Humulin
2. Intermediate filament
3. Flagellin
4. Tubulin

Q. Mitotic poison is

1. Nitrate
2. Carbon dioxide
3. Colchicine
4. Trehlose

Q.

Which of the following is true about spindle fibres?

1. Interchromosomal fibres

2. Interzonal fibres

3. Chromosomal fibres

4. Continuous fibres

Q. The microtubules are made up of ______ proteins.

1. tubulin
2. myosin
3. condensins
4. actin

Q. Spindle fibre is made of

1. Humulin
2. Tubulin
3. Intermediate filament
4. Flagellin

Q. Maam what us the difference btw these 3. Coated vesicle, smooth vesicle, secretory vesicle. Are those 3 types of Vesicles formed in Golgi body?

Q. Colchicine interferes with cell division because of

1. Splitting of chromosomes
2. Non-pairing of chromosomes
3. Double replication of chromosomes
4. Non-formation of spindle

Q.

Protein subunit found within microtubules is:

1. Collagen

2. Tubulin

3. Myosin

4. DNA

Q. Terminal transferase is used

1. to add base at the 3' end of the DNA
2. to add base at the 5' end of the DNA
3. to carry out nick translation
4. to transfer phosphate at the 3' end of the DNA

Q. Spindle fibre attaches onto:

1. Telomere of the chromosome
2. Kinetochore of the chromosome
3. Centromere of the chromosome
4. Kinetosome of the chromosome

Q. Colchicine prevents

1. Condensation of chromosomes
2. Completion of metaphase
3. Interphase
4. Replication of chromosomes