• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10
  11. 11
  12. 12
  13. 13
  14. 14

P2 - Physiology of fluid balance

Extracts from this document...


P2 - Explain the ways in which materials move into and out of cells M2 - Explain the factors that influence the movement of materials into and out of cells D1 - Analyse the role of the phospholipid bilayer in terms of the movement of materials into and out of cells Within this assignment I intend to achieve P2, M2 and D1. I will explain the ways in which various materials move into and out of cells by explaining the processes of diffusion, facilitated diffusion, osmosis, active transport, endocytosis and exocytosis. In order to achieve M2, I will explain the relevant factors which influence the movement of materials. For instance, I will consider; size, distance, temperature and concentration gradient which are all relevant to the diffusion of a molecule through a phospholipid bilayer. To achieve D1, I will carry out further research to analyse the role of the phospholipid bilayer in terms of the movement of materials into and out of cells. It is essential that the environment within the human body is maintained in order for the body to function effectively. Cells within the body require the environment to remain the same so they able to carry out their specific jobs, for instance, if the environment was not maintained within the body, then red blood cells would not be able to supply the body with the oxygen it requires and as a result the body will not be able to function appropriately. Maintaining a suitable environment within the body depends largely on the way in which substances pass in and out of cells. Cells are very complex factories which need to import raw materials, and also export any waste materials within the cell. There are three different states of matter which I will describe within this assignment. Matter can be defined as; 'a material that has substance and occupies space.' Stretch, Beryl, 2007, Health and Social Care Book 2, pg 169 The three states of matter include; * Solids - e.g. ...read more.


For instance, membranes within the lungs always have a concentration gradient as there is always diffusion of oxygen and carbon dioxide from the alveoli and into the circulatory system and visa versa. The membrane within the lungs which have become thick as a result of a build of carbon dioxide will affect the rate of diffusion within the lungs considerably. The membrane will be much thicker and molecules will therefore find it harder to diffuse over a larger distance, making the process of diffusion much slower. Another example is; if an artery is narrowed the diffusion rate will also be much slower. High cholesterol levels are associated with coronary heart disease and the build up of fatty deposits within the endothelium of the blood vessel will lead to the narrowing of the lumen. 'The distance over which diffusion occurs is known as the length of the diffusion pathway.' Boyle M and Senior K, 2002, Collins Advanced science Human Biology, pg 72 As a short diffusion pathway is required in order for molecules to diffuse into and out of cells effectively, cells are situated no more than several micrometres away from a capillary. The overall diffusion rate at which a substance diffuses through a membrane also depends on the surface area that is in contact with the substance. For example, the microvilli within the intestines has a large surface area due to the folding of the membrane. This will allow diffusion to happen quickly as there is more space and opportunity for the molecules to diffuse through into or out of the cell. Temperature can influence the rate of diffusion across a membrane as the movement of the molecules increases with an increase in temperature due to kinetic energy of the particles. Diffusion takes place faster at body temperature than it does at room temperature. The following formula was taken from; Bailey M & Hurst K, 2000, Collins advanced modular sciences Biology, pg 29 The rate at which a substance diffuses can be calculated using ...read more.


Other examples include; the mitochondrial inner membrane has high amounts of functional electron transport system proteins and the plasma membranes within the body has less protein due to fewer functions, the plasma membrane mainly carries out ion transport of materials across the membrane. A specific example of variations between cell membranes is the sarcolemma. Sarcolemma is the name given to the cell membrane of a muscle cell; skeletal, cardiac and smooth muscle. This type of cell membrane consists of a plasma membrane and also consists of a thin layer of polysaccharide material containing thin collagen fibres. As the sarcolemma is the membrane of a muscle cell it is specifically designed to receive and conduct stimuli. If any alterations are made in the sacrolemma it can potentially lead to a disorder known as; muscular dystrophy. Muscular Dystrophy can be defined as; 'The muscular dystrophies (MD) are a group of more than 30 genetic diseases characterized by progressive weakness and degeneration of the skeletal muscles that control movement.' http://www.ninds.nih.gov/disorders/md/md.htm#What_is The mechanism of one type of Muscular Dystrophy is the lack of functional dystrophin; meaning the cell membrane (sacrolemma) is not attached to the cytoskeleton and therefore when the muscles contract the cell membrane does not work together with the interior of the cell. The sacrolemma has calcium channel proteins within it and therefore, as a result of the laxity of the membrane these channel proteins will be unable to open leading to an increase in calcium ions within the cell. Overall within this assignment I have met the criteria in order to achieve P2, M2 and D1. I have looked at a range of processes which allow molecules to diffuse through the membrane. I have also explained some of the factors which can influence this and what effect they have on the membrane. I have also looked closely at the functions of the membrane itself. ?? ?? ?? ?? 1 Laura Wingfield Group B Physiology of fluids - P2, M2 D1 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Healthcare section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Healthcare essays

  1. Marked by a teacher

    The Role of Energy in the Body and the Physiology of Three Named Body ...

    5 star(s)

    With the ventricles in diastole, the atrio-ventricular valves are pushed open with the blood that has been filling the atria. When the ventricles are about 70 per cent full, the atria contract to push the remaining blood in rapidly and the next cycle has begun.

  2. Describe the distribution of water in the body and the function of constituents of ...

    Fluid mosaic model shows the structure of the phospholipids membrane with all other compounds that are included in it i.e. carrier proteins, glycoprotein, cholesterol etc. 4. Molecules have a tendency to move from an area of high concentration to an area of low concentration down a concentration gradient.

  1. Describe the role of energy in the body and the physiology of three named ...

    The cardiovascular system then delivers these simple soluble materials through the blood stream and into the cells and liver. The beat and the pumping of the heart is what causes this transportation. As this is occurring the respiratory system is constantly taking in fresh oxygen and getting rid of waste

  2. Lymph is formed when the lymphatic system carries away waste from the tissue. The ...

    capillaries * The lymphatic capillaries that pick up digested fat in the villi of the intestine are known as lacteals * Empties clean lymph back into the blood stream 3. Describe the structure & function of a lymphatic vessel The capillary bed handles large volumes of fluid during systemic and pulmonary circulation.

  1. Diabetes and Insulin.

    lipid concentrations in study patients with type II diabetes, or non-insulin dependent diabetes mellitus, the most prevalent type of diabetes (Medical College of Wisconsin). High-fiber foods that Morgan should start to eat are fruits (raspberries, pears [with the skin], apples [with the skin], blueberries, etc.), grains, cereals, & pasta (whole-wheat

  2. Unit 8: Psychological Perspectives for Health and Social Care - P2, P3, M2 and ...

    The child was happy and outgoing before her younger brother was born, she started to throw tantrums and started to wet herself frequently, which she previously didn?t do before her brother was born. The health visitor explained to her mother that the little girl is going through regression because her

  1. Unit 5 Anatomy and Physiology P1 and P2 Cell Compnents and Tissue Structure

    The outside surface is known as ?Rough ER? because it has ribosomes attached to it. The ribosomes make protein from amino acids and the rough ER collects and transports the proteins made by the ribosomes. Smooth ER doesn?t have ribosomes and is responsible for steroid production.

  2. Unit 5 Anatomy and physiology in health and social care

    The inner membrane is infolded many times, forming a series of projections (called cristae). The mitochondrion converts the energy stored in glucose into ATP (adenosine triphosphate) for the cell. They are represented by raisins. Centrosome - a small body located near the nucleus - it has a dense centre and radiating tubules.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work