Cell Adaptation Essay
Cells found in Animals and plants as well as bacteria themselves being single celled organisms. Cells can perform a number of different roles. In order to work in the most effective and efficient manner these cells have adapted their shape to best suit the particular function the cell undertakes.
Neurones are cells which are essential in the nervous system of animals, they carry impulses along their length through a process which sees an electrical current generated and passed along the neuron though the polarisation and depolarisation of the cell through action potentials managed by sodium potassium pumps and gated ion channels. The first way neurones have adapted their shape to suit their function by having a long axon which means that action potentials can be sent from one part of the body to another very quickly. One long axon means less delay, as the signal takes longer to travel if it needs to be converted into chemicals at synapses; a single long axon means the number of times this conversion needs to take place is reduced.
Neurones have also adapted to produce a myelin sheath which surrounds and insulates the axon. It is produced by Schwann cells and prevents the Sodium and Potassium ions from leaving the cell. Neurones have also adapted to develop Nodes of Ranvier; these are gaps between the myelin sheath which allows salatory conduction to occur. Salatory conduction speeds up nerve impulse transmission, myleniated cells are up to 100x faster than unmyleniated axons. Salatory conduction also conserves energy as it means sodium potassium pumps only have to operate at the nodes meaning fewer ions have to be actively transported.
Ciliated Epithelial cells are found lining many parts of the body; these include the respitory canals, the ovary, the small intestine etc. These commonly found cells have adapted to have many microscopic protrusions called Microvilli; these microvilli increase the surface area of the cell which means that there area over which diffusion can take place. Ciliated cells can also have very thin membranes; this means diffusion can take place more easily. These two adaptations are most commonly found in the ciliated cells in the small intestine which have adapted these features to allow the highest quantity of nutrients to be absorbed through diffusion.
The Microvilli also have the function of being able to move things along the length of a section of the body. The cells have adapted these protrusions so that they can wave or pulse, examples of the use of this feature is in the Ovary where microvilli move the ovum; and in the respitory system where mucus is moved along to prevent its build up and the spread of disease.
Red blood cells are another type of animal cell which have adapted to their function. Red blood cells are one of the only cells found in an animal which doesnt have a nucleus. The absence of a nucleus along with a biconcave structure gives the red blood cell