Nucleoplasm, Biology

Assignment Help:

NUCLEOPLASM OR KARYOPLASM OR KARYOLYMPH OR NUCLEAR SAP

Nucleoplasm and cytoplasm name proposed by E. Strassburger. Chemical composition of nucleoplasm given by Kossel. Compositions of nucleoplasm is similar to cytoplasm but it contains high concentration of nucleotides in form of triphosphates. Nucleoplasm have enzymes for glycolysis. Thus nucleus obtains its own energy by glycolytic pathway.

Inside nucleoplasm, there is a net work of fine threads. These threads called chromatin fibers. Chormatin name proposed by Flemming. Chromatin threads composed of DNA, RNA, histone protein & nonhistone protein. Chromatic threads contain genetic information Alkaline stain (Acetocarmine, Haematoxylene, Feulgen) are used to stain chromatin. In stained preparation under light compound microscope chromatin net work appears differentiated in two parts :-

1. Euchromatin - Lightly stained thin and diffused part of chromatin. This part have less histone and more acidic proteins. Euchromatin is more active part of Chromatin and its DNA undergoes rapid transcription. During nuclear division euchromatin replicates in S-phase of cell cycle. It is affected by pH, temperature, poisons etc. It takes part in crossing over. It is formed by loose spiralisation of nucleosome strands.

2. Hetrochromatin - Darkly stained thick and condensed part of chromatin. This part have more histone and less acidic proteins Heterochromatin is genetically a less active part of chromatin. Heterochromatin forms stop points in transcription.

  • Large granular masses of heterochromatin are called false nucleoli/ karyosomes/ chromocentres.  False nucleolus stainable by basic dyes.
  • It is formed by solenoid type of coiling of nucleosome containing DNA strands. It does not take part in crossing over.
  • It is less affected by pH, temperature, poison etc. Replication occurs late in S or G - costitutive and facultative phase. It is of further two types
  • Constituting heterochromatine is present in all cells in all stages of life cycle whereas facultative heterochromatin develops secondarily.
  • In mammalian females one X chromosome becomes heterochromatin during embryogenesis but becomes normal in oocytes. It forms barr body, discovered by Barr and Bertman.
  • It presents indicates that sex of embryo is female. Higher number of barr bodies shows abnormal embryo. Barr body present as drumstick in neutrophils. Euchromatin and Heterochromatin discovered by Emil Heitz. Heteropycnosis - Differential staining of chromatin is called heteropycnosis

Related Discussions:- Nucleoplasm

Carbohydrates requirement in pectic ulcer, Q. Carbohydrates requirement in ...

Q. Carbohydrates requirement in pectic ulcer? Carbohydrates: These should provide around 55 to 65% of the daily intake. Emphasis - J should be laid on the consumption of 60th s

Cyclins and cyclin-dependent kinases, Rhythmic fluctuations in the abundanc...

Rhythmic fluctuations in the abundance and activity of cell-cycle control molecules pace the events of the cell cycle. • Kinase - a protein which activates or deactivates another

What are the three parts of a dna nucleotide, What are the three parts of a...

What are the three parts of a DNA nucleotide, and how are they connected to each other? The three types are a deoxyribose sugar, a phosphate group, and a nitrogenous base. The

Define nitrogen requirements in pregnancy and lactation, Define Nitrogen re...

Define Nitrogen requirements in Pregnancy and Lactation? The nitrogen accretion in the pregnant woman (assuming that the foetus weighs 3.3 kg at term), estimated by the Committ

How to obtain the correct healing collar, To obtain the correct Healing Col...

To obtain the correct Healing Collar the following steps need to be followed: - Determine the si-e of the implant platform.76 Practical Manual - Select the emergence profile

Scientific activity, describe the factors which decide the broad area of sc...

describe the factors which decide the broad area of scientific activity?

Hazard analysis, Hazard Analysis Two steps recognized as preliminary a...

Hazard Analysis Two steps recognized as preliminary and detailed analysis of hazard are taken. Preliminary Hazard Analysis (PHA) serves two aims: (i) It can expedite bringi

What are the benefits of cardiac rehabilitation, What are the benefits of c...

What are the benefits of cardiac rehabilitation ? The most substantial benefits include: 1 Improvement in exercise tolerance. 2 Improvement in symptoms. 3 Improvement in blood

Descibe the lymphatic system, Q. What is the lymphatic system? The lymp...

Q. What is the lymphatic system? The lymphatic system is a network of specialized valved vessels that drain interstitial fluid (lymph), the lymphatic system is as well responsi

Techniques of counselling, Counseling is a process whereby a qualified pers...

Counseling is a process whereby a qualified person purposefully assists another person to handle his or her problems. Counselling is not just giving advice. It is dependent  on mut

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd