Cellular and Molecular Biology concepts - Speech or Presentation Example

Cellular and Molecular Biology Concepts Pick two biomolecules and/or organelles and explain how they are associated and how they work together in the cell. Cells are made up of important functional components known as organelles which severe several biological and physiological functions. The functions of a cell are executed through coordinated activity between various organelles of the cell. Two such organelles are nucleus and ribosomes which, through coordination of functions produce various proteins responsible for different structural and functional activities of the body.

Nucleus is one of the organelles found in the cell that is enclosed with a membrane. It is found in eukaryotic cells (Cech, 2000). Most of the genetic material of the cell is in the nucleus and this genetic material is organized in the form of long linear DNA molecules which are present in multiple numbers. The genetic material are present in complex associations with various proteins, known as histones to form chromosomes. Genes which are present within the chromosomes form the nuclear genome of the cell (Lamond, 1998).

The main function of the nucleus is to maintain the integrity of the genes present in the chromosomes and regulate their expression. Thus, it can be said that the organelle, nucleus, is the control center of any cell. The nucleus is covered with a nuclear envelope which is basically a double membrane. The membrane separates the nucleus from other contents present in the cytoplasm. It contains some pores which host channels to facilitate movement of molecules and ions between the nucleus and the cytoplasm.

The movement of these molecules is controlled carefully. For the purpose of movement of larger molecules, carriers proteins are present for active transport. The nucleus has a nuclear lamina within itself that provides mechanical support to the various contents of the nucleus. Ribosomes are important organelles of any biological cell where proteins are manufactured using information from the RNA and building blocks from the aminoacids (Rhodney, 1996). The sequence of aminoacids is decided by the sequences of coding in the RNA which in turn is decided by the genetic material in the nucleus.

Thus, protein production by ribosomes is decided by the DNA composition in the genetic material packed in the chromosomes of the nucleus. This is known as the central dogma of molecular biology. The genes have a certain DNA sequence which is copied into a RNA, known as a mesneger RNA (mRNA). mRNA is read by the ribosomes and assimilates amino acids to form proteins. This is known as translation (Rhodney, 1996). During translation, the ribosomes bind to the template mRNA. The aminoacids are then attached based on the sequence to transfer RNA (tRNA).

Ribosomes are basically complexes of proteins and RNAs. They have 2 subunits, a smaller subunit and a larger subunit. The smaller subnit binds to the messenger RNA and the larger one to the tRNA and amonoacids. Thus, through coordination, ribosomes and nucleus help in the production of proteins from various aminoacids. References Cech, T (2000). "Structural biology. The ribosome is a ribozyme". Science, 289 (5481), 878–9 Lamond, A. I., and Earnshaw, W.C. (1998). Structure and Function in the Nucleus.

Science 280 (5363), 547–553. Rodney R., Richard P. (1996). "Ch3". Human Physiology (3rd ed.). London: Saunders College Publishing.