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Q 1: In a Nucleus what structure attaches chromatin to the inner membrane of the nuclear envelope?

A) Nuclear Lamins
B) Precursor RNA Molecules
C) Endoplasmic reticulum
D) Lamin Kinase


a, lamins . Not sure though, do you have an explanation ?


You are 100% correct! Nuclear lamins attach chromatins to the inner membrane of nuclear envelope and it participate in the breakdown and reformation of the nuclear envelope during the cell cycle.


Q 2: If you add salt and alcohol to B-DNA, it will change into;

D) A & B


I knew there are laminins in nuclear membrane, but had no idea about chromatins attachments to it.


For 2nd question : double cool

raised eyebrow



Q2 Answer is B; A-DNA

The normal right-handed "double helix" structure of DNA is in B form.
It turns every 3.4 nm & has 10 base pair per turn.

In a solution with higher salt concentrations or with alcohol added, the DNA structure may change to an A form, which is still right-handed, but every 2.3 nm makes a turn and there are 11 base pairs per turn.

Another DNA structure is called the Z form, because its bases seem to zigzag. Z DNA is left-handed. One turn spans 4.6 nm, comprising 12 base pairs.


Q3: In a cell, the site of posttranslational modification and sorting of newly synthesized protein and lipids is;

A) Rough Endoplasmic Reticulum
B) Ribosomes
C) Golgi Apparatus
D) Lysosomes


Q3: Ans is C


Q4: Nissl bodies correspond to which of the following cytoplasmic organelles?

A. Golgi apparatus

B. Mitochondria

C. Nucleoli

D. Rough endoplasmic reticulum

E. Smooth endoplasmic reticulum


d my answer


Q4 correct answer is D.rough endoplasmic reticulum.

Nissl bodies (trigoid) in form of large basophilic granular areas are represented by rough endoplasmic reticulum and polysomes and are sites of active protein synthesis.


Q3. C

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