Structure of Chromosomes

Q.

Q. What is giant chromosome?

also explain its types.

Q.

What is the function of centrioles?

Q. Number of bivalents are 8 in prophase I. What is the number of chromosomes during anaphase II?

1. 4
2. 8
3. 32
4. 16

Q.

Describe the ultrastructure of eukaryotic chromosomes.

Q. A single human cell has approximately _____ long thread of DNA distributed among its _____ chromosomes.

1. 2 cm, 46
2. 2 metre, 46
3. 2 cm, 23
4. 2 metre, 23

Q.

What is a centromere? How does the position of centromere form the basis of classification of chromosomes? Support your answer with a diagram showing the position of the centromere on different types of chromosomes.

Q.

How many chromatids are in a chromosome?

Q.

Which of the following cell organelles is responsible for extracting energy from carbohydrates to form ATP?

1. Lysosome

2. Ribosome

3. Chloroplast

4. Mitochondrion

Q.

Match the type of RNA in column I with its function in column II.

Column I	Column II
1. mRNA	A. reads the genetic code
2. tRNA	B. catalytic role
3. rRNA	C. acts as a template

1. 1-A, 2-B, 3-C
2. 1-B, 2-C, 3-A
3. 1-C, 2-A, 3-B
4. 1-C, 2-B, 3-A

Q. Nucleoproteins are

1. proteins found in the nucleus
2. pigment molecules
3. proteins linked to a nucleic acid
4. novel proteins

Q. Small disc-shaped structures at the surface of the centromeres that appear during metaphase are:

1. Kinetochores
2. Metaphase plate
3. Spindle fibres
4. Chromatid

Q.

What Is The Basis Of The Classification Of Chromosomes?

Q. Centromere is required for
(1)transcription
(2)crossing over
(3)cytoplasmic cleavage
(4)movememt of chromosome to poles

Q.

Assertion : A cell membrane shows fluid-mosaic behaviour.
Reason : A membrane is composed of lipids and proteins.

1. Both Assertion and Reason are correct and Reason is the
   correct explanation of Assertion.

2. Both Assertion and Reason are correct, but Reason is not
   the correct explanation of Assertion.

3. Assertion is correct but Reason is incorrect.

4. Assertion is incorrect but Reason is correct.

Q. Assertion: Eukaryotic hnRNA contains introns that are removed during RNA processing
Reason: Splicing of exons suggests the dominance of the RNA world

1. Both assertion and reason are true and the reason is the correct explanation of the assertion
2. Both assertion and reason are true but the reason is not a correct explanation of the assertion
   
3. The assertion is true but the reason is false
   
4. Both assertion and reason are false
   

Q. Identify the nucleosome from the following options.

1. DNA + H2A + H2B + H3 + H4
2. DNA + H1 + H2 + H3 + H4
3. DNA + 2 (H2A + H2B + H3 + H4)
4. DNA + 2 (H1 + H2 + H3 + H4)

Q.

Define satellite.

Q. Read the assertion and reason carefully to mark the correct option in question.

Assertion: Every chromosome essentially has a kinetochore on the sides of which centromeres are present.

Reason: Based on the position of centromere or primary constriction chromosome can be classified into five types.

1. If both assertion and reason are true but the reason is not the correct explanation of the assertion.
2. If assertion is true but reason is false.
3. If both assertion and reason are false.
4. If both assertion and reason are true and the reason is the correct explanation of the assertion.

Q. Find out the correct option on the basis of the following diagrams.

1. A-Satellite, B-Secondary constriction C-Short arm, D-Long arm
2. A-Satellite, B-Centromere C-Short arm, D-Long arm
3. A-Secondary constriction, B-Satellite, C-Long arm, D-Short arm
4. A-NOR, B-Secondary constriction, C-Short arm, D-Long arm

Q.

What are the phases of Receptor-mediated endocytosis for Cholesterol uptake?

Q. Eukaryotic chromosomes are thousands times longer than a typical cell. How do chromosomes fit inside a eukaryotic nucleus?

1. The genetic material remains distributed in the nucleus, mitochondria, and chloroplast
2. The chromosome is present in pieces, thus it fits the size of the nucleus
3. The DNA remains coiled around proteins to form nucleosomes which further coils to compact itself
4. The genetic material remains bound to the nuclear envelope, forming invaginations

Q. Which of the following terms refers to the terminal ends of chromatids?

1. Telomere
2. Centromere
3. Kinetochore
4. Satellite

Q.

Which one of the following carries extra nuclear genetic material?

1. Golgi apparatus

2. Ribosomes

3. Chromosome

4. Plastids/Mitochondria

Q.

What are the 5 major types of histones?

Q.

What is the constituency of telomeres of eukaryotic chromosomes?

Q. Choose the correct options from the following:
A. Centrioles are made up of nine evenly spaced peripheral fibrils of tubulin.
B. The centrioles in a centrosome lie parallel to each other.
C. The central part of the centriole is also proteinaceous and called the hub.
D. Centrioles form the spindle fibres that give rise to spindle apparatus during cell division.

1. A, B, C
2. B, C, D
3. A, C, D
4. A, B, D

Q. Centromere is required for

1. Movement of chromosomes towards poles
2. Cytoplasmic cleavage
3. Crossing over
4. Transcription

Q.

Question 17

What attributes does a chromatid require to be classified as a chromosome?

Q. Which of the following is not true about polytene chromosome?

1. They are chromosomes which have developed from standard chromosomes
2. Polytene chromosomes are, involved in intense secretory functions.
3. They are cells that contain multiple sets of chromosomes and not held together at a single point.
4. They are formed due to repeated rounds of DNA replication without any cell division and are held together at a single point,

Q.

What are centrioles like?