Every individual possess billions of cells in their body but not only is the human body functional With cells but also contains tissues, organs and systems which is what the human body is made up of. The cell carries out vast numbers of chemical reactions which processes in order to make up the essence of life (Moonie N, Aldworth C, Billingham M & Talman H ,2012). Cells are usually grouped together with other cells carrying out particular tasks (Moonie N, Aldworth C, Billingham M & Talman H, 2012); the cells that are grouped are known as the tissues. Tissues are commonly grouped together to form an organ. Then finally the organs are responsible for the functions in the human body which are called systems.
Cells vary in size and shapes which are easier to observe with a microscope either using an electron microscope which are useful to see the details of the cell. Not all types of cells are exactly like others but they do have the same basic parts. In general all cells have three main parts; an animal cell has three features in common which are the cell membrane, the nucleus and organelles.
Cell membrane
Each cell has a cell membrane it is also known as the plasma membrane which is a fragile, transparent outer boundary which forms around the cell to separate them from the surrounding environment (Marieb,E N, (2012).), the membrane allows what comes in and out of the cell. The structure of the cell membrane consists of two layers of phospholipids (fatty substances) with large protein molecules inserted completely into the layers. The phospholipids are an important component of the cell membrane as they form a lipid bi-layer which has a head that is electrically charged and hydrophilic (Waugh, A & Grant, A ,2012.) which means it is water soluble and arranges itself facing the outer surfaces of the membrane, it also has a tail which has no electrical charge and his hydrophobic (Waugh, A &
References: n/a. (2012). ROUGH ENDOPLASMIC RETICULUM. Available: http://epiehonorsbiology.wikispaces.com/Rough+endoplasmic+reticulum. Last accessed 23/9/12. Moonie N, Aldworth C, Billingham M & Talman H (2012). BTEC Level 3 National Health and Social Care BOOK 1. United Kingdom: Pearson Education Limited. P181 CYTOPLASM - Annenberg Foundation