Nuclear & Cell membranes; the membranes surrounds all living cells and is also the most important organelle. Its function is to control the substances that move in or out of the cells and has other properties. The membranes that surround the nucleus and other organelles are almost identical to the cell membrane. It is composed of proteins, phospholipids and carbohydrates that are arranged in a fluid mosaic structure.
Nucleus; the nucleus is the control centre of the whole cell. The nucleus of living cells contains genetic material that determines the structure and function of the cell it’s controlling.
Nucleolus; the nucleolus is in the nucleus where rRNA genes exist and are transcribed. The resulting rRNAs and ribosomal proteins are combined to form the ribosomal subunits. The function of the nucleolus is the production of ribosomal subunits.
Chromosomes; the chromosomes main function is to control the activities of a living cell. They are vital for the cell division process and are responsible for the division, replication as well as creation of daughter cells, which contain sequences of DNA and proteins.
DNA; DNA is made up of units known as nucleotides and are repeated along the length of the molecule. A nucleotide is made up of a base, sugar and phosphate grouping. DNA is made up of 4 different bases, these are adenine, guanine, cytosine and thymine, also known as A, G, C and T. These bases will always combine the same way, Adenine and Thymine combine together and Guanine and Cytosine combine together. All bases are held together by a hydrogen bond, the ladder is twisted into a spiral shape, it’s often known as a double helix. The DNA in a cells is used to form a code for cell metabolism. The metabolism is governed by enzymes, these catalyse all reactions within the cell. The enzymes are proteins and the particular stretch of DNA forms the code needed for production of the enzymes and other proteins. The proteins are made up of amino acids, DNA