Cells Functions

structure of these cells is a flying disk shaped like a donut, this is so maximum haemoglobin can be carried allowing maximum amount of oxygen to be transported.
Sperm cells
A sperm cell is the male reproductive cell that carries the male portion of chromosomes and deoxyribonucleic acid (DNA) information to be fused with the female egg or ovum. The sperm cell carries various amount of heredity information inside the cell nucleus. There are various ways in which sperm can be transmitted to the egg for fertilization. The sperm cell can be sent to the female egg through sexual intercourse. Starting from puberty and leading through to old age, the testes will produce over a thousand sperm cells every second. The sperm goes through a process called spermatogenesis this is where the cell will go through multiplication (mitosis), growth and maturation (Boyle and Senior, 2002, p345). The sperm cell comprises of three sections, the head, the mid piece and the tail which is kept in shape by the plasma membrane. The head of the sperm is round in shape and contains the nucleus and acrosome. The nucleus is the control centre of the cell and holds (DNA), this is what makes this cell a eukaryotic cell. The acrosome is an organelle that forms on the outside of the head they derive from the Golgi apparatus and contain digestive enzymes. Acrosomes are needed to break down the outer membrane of the egg, so that the two nucleuses' can fuse together thus producing a zygote (fertilized egg).The mid piece holds the centriole and mitochondrion. The centriole is necessary for the first mitotic division of the zygote; this is where the zygote undergoes rapid cell division, producing a cluster of cells with no significant growth. The mitochondria is simply the energy centre or the cell, this is the power plant and is wrapped around the mid piece of the sperm cell. The final part of the sperm cell is the tail also known as the flagella (this is also found in the bacteria cell) this helps the sperm with movement on its journey to the egg.
Skin cell
Skin is made up of stratified epithelial cells. These cells act as protection. There are many layers of epithelial cells that are effectively dead. You shed your skin as a new layer is developed underneath which maintains a fresh layer of dead cells lining your skin. The skin cells do not allow anything to pass through them so prevent unwanted substances from moving into your body there are two main layers of skin epidermis and Dermis. The subcutaneous layer is the fatty layer underneath the skin (‘subcutaneous’). It can vary considerably in thickness from person to person depending mostly on whether they are overweight
In conclusion, there are many cells within the human body with some being specialised cells. They are constantly repairing and producing new cells through the process of mitosis. The four cells mentioned above all have their own specialised functions and a very important part to play in the human body's day to day life.