write a short note on nucleus
Answers
Nucleus : It is known as control room or heart of a cell.
⭐ Diameter : 4.c micrometre.
⭐ It is not present in matured RBC.
⭐ Nucleus was discovered by Robert Brown in 1831.
⭐ It is distinguished in 4 parts :
✔ Nuclear membrane.
✔ Nucleoplasm.
✔ Nucleolus.
✔ Chromatic.
Nuclear membrane : Nucleus has double layered covering called membrane. It has numerous minute pores. These pores allows the transfer of materials from inside the nucleus to cytoplasm.
Nucleolus : It is sperical in shape. It is first recognised by Fontana in 1874. It constitutes 35% mass of Nucleus.
Nucleoplasm : It is made up of nucleic acid, proteins, enzymes, lipids and minerals.
Chromatin : These form chromosomes during cell division. Chromosomes contain information for inheritance of features from parents to next generation in the form of DNA. Chromosomes are composed of DNA and proteins. Functional segment of DNA are called genes.
Functions of Nucleus : It plays an important role in cellular reproduction. It co-ordinates the cell activities which include growth intermediary metabolism protein synthesis. Nucleus is present in eukaryotes. Organisms whose cells lack a nucleus membrane are called prokaryotes and organisms with cells having a nucleus membrane are called eukaryotes.
It was discovered by Robert Brown in 1831.It controls and coordinates all functions of the cell.It also determines the characteristics features of living organisms.There are thred like structure called nucleus.