CELL ORGANELLES

1008 WD

Its function is to control the cell's activities and retain the chromosomes.

The nucleus is bound by a double membrane, the nuclear envelope. The nuclear envelope has pores in it to allow the transport of mRNA. The cytoplasm like material is called nucleoplasm which contains chromatin (coils of DNA and histone proteins), it is chromatin that condenses to form chromosomes during cell division.

Within the nucleus is a small spherical body called the nucleolus which manufactures RNA to from ribosomes.

Ribosomes

Are very small organelles but are present in large numbers.

They are made up of two subunits, the large subunit and the small subunit.

70s ribosomes are found in prokaryotes whilst 80s ribosomes are found in eukaryotes. They are involved in protein synthesis.

They can either be found free in the cytoplasm or on the outer surface of the rough endoplasmic reticulum.