• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

structure and function of the digestive system and nutrients

Extracts from this document...


Macronutrients Carbohydrates Carbohydrates have three main purposes: * To provide the body with energy * To allow the body to store and transport energy * To aid in bodily needs e.g. immune system, fertilization, pathogenesis, blood clotting, and development. The structure of carbohydrates consist of three elements, these are carbon, hydrogen and Oxygen. Carbohydrates can be broken down into two groups these are simple carbohydrates and complex carbohydrates. Simple Carbohydrates are also known as simple sugars and these include substances such as Sucrose (a combination of Glucose and Fructose). Other examples may include Lactose (a combination of Glucose and Galactose). Simple sugars may also be broken down into the amount of bonds they have; monosaccharide's consist of just one sugar, disaccharide consist of two sugars combined, and finally polysaccharides' consist of many sugars, usually three or more. These carbohydrates all gain quick access to bloodstream providing a slow, prolonged release of energy. Complex Carbohydrates come from starch and they are polymers made up of many monosaccharide's' joined together by glycosidic bonds. They are therefore very large, often branched, macromolecules. They tend to be solid, insoluble in water, and have no sweet taste. They go through the digestive system where they are broken down and transported to places in need of energy- it gives a steady release of energy over a prolonged period of time. There are many common sources of carbohydrates, some of the sources for simple carbohydrates are: * Sweets * Cakes * Chocolate * Biscuits * Jam Here are some examples of complex carbohydrates * Potatoes * Pasta * Spaghetti * Fruit * Whole Grain cereals e.g. ...read more.


Vitamin D is formed in the skin when it is exposed to sunlight Rickets Vitamin E Protects tissues against damage; promotes normal growth and development; helps in normal red blood cell formation Pure vegetable oils; wheatgerm, wholemeal bread and cereals, egg yoke, nuts sunflower seeds May cause muscular dystrophy Vitamin K Used by the liver for the formation of prothrombin Green vegetables Bleeding due to delayed clotting times caused by lack of clotting factors. Patients may show signs of bruising easily and have nosebleeds Minerals Minerals are essential for the maintenance of good health and the prevention of a number of diseases. Like vitamins, minerals cannot be manufactured in the body and without them we would not survive. Name Function Source Calcium Essential for strong bones and teeth. Also takes part in the body's immune system. Dairy Products Tofu Almonds, Brazil Nuts, Hazelnuts Iron Needed for healthy blood and muscles. It plays an essential role in the production of the body's white blood cells and in the activities of the immune system. Haem iron found in meat and offal (essentially the iron from blood and muscle). Non-haem iron derived from some plants, grains and nuts Magnesium Helps to regulate potassium and sodium levels within the body, which are involved in the control of blood pressure. Apricots, bananas, figs, prunes, raisins Brown rice, granary bread, wholemeal bread, wholewheat pasta, nuts, pulses, Courgettes, green leafy vegetables, okra, parsnips, peas, sweet corn Lean meat Milk, yoghurt. ...read more.


Soluble Fibre lowers cholesterol levels and controls blood sugar Sources of Insoluble Fibre include: * beans * brown rice * fruits with edible seeds * lentils * maize * oats * wheat bran, wholegrain breads, wholegrain cereals, wholemeal breads, wholemeal cereals, wholemeal pasta, wholewheat flour Sources of Soluble Fibre include: * apples * barley * citrus * guar gum * legumes * oats * pears * strawberries RDA's Recommended Daily Allowance (RDA) is the sufficient intake of a nutrient deemed correct for 97% - 98% of healthy individuals in each life-stage and gender. Nutrient Daily intake (g) Percentage of daily intake Protein Men- 55g Women- 45g 10%- 15 % Carbohydrates Men- 275g Women- 203g 47% - 49% Fats Men- 95g Women- 70g 30% - 35% Fibre Men- 18g Women- 18g 1% - 5% Vitamin Men Women A 0.7mg 0.6mg B1 1.0mg 0.8mg B2 1.3mg 1.1mg Nicin 19mg 15mg B6 1.4mg 1.2mg Pantothenic acid 5mg 5mg Folic acid 0.2mg 0.2mg Biotin 0.03mg 0.1mg B12 0.002mg 0.002mg C 40mg 40mg D 0.01mg 0.01mg E 10mg 8mg K 0.8mg 0.06mg Mineral Quantity Calcium 800mg Iodine 150mcg Iron 14mg Magnesium 300mg Phosphorus 800mg Zinc 15mg Estimated Average Requirement (EAR): This is an estimate of the average requirement for energy or a nutrient - approximately 50% of a group of people will require less, and 50% will require more. Safe intake: This is used where there is insufficient evidence to set an EAR. The safe intake is the amount judged to between the stages of deficiency and excess intake. There is no evidence stating that intakes above these levels are safe and in some instances they could have toxic effects. ...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 Anatomy & Physiology 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 Anatomy & Physiology essays

  1. Physiology Within Sport

    lungs the pressure of carbon dioxide is decreased and so also is the hydrogen ion concentration, and as you can see on the graph this causes the curve to shift to the left allowing a much more efficient oxygen uptake within the lungs.

  2. Muscle fibre types.

    The development of the sarcoplasmic reticulum is high, which allows the release of more calcium ions than a slow twitch fibre. This means that the troponin can bind with the calcium to create a fast contractile speed, and high motor unit strength.

  1. The human bodys immune system

    When we are injured blood clots at the injury site, sealing the breach to prevent entry of bacteria. * Biological defense. Normally a vast number of non-pathogenic bacteria live on the skin and mucous membranes. These do not harm the body but they compete with pathogenic bacteria, preventing them from gaining a foothold from which to launch a full-scale infection.

  2. Looking at the skeletal and muscular system and the use of this system during ...

    * The kicking foots shoulder should now draw into the body using medial rotation, muscles used being the deltoid, trapezuis and the pectorials major. * The hip should do exactly the same and draw in towards the body showing medial rotation using the quadriceps.

  1. Respiratory system

    An increase in diameter is called bronchodilation. A decrease in diameter is called bronchoconstriction. http://www.probertencyclopaedia.com/cgi-bin/res.pl?keyword=Bronchioles&offset=0 http://en.wikipedia.org/wiki/Bronchiole Lungs The lungs are a very important part of the respiratory system. The left lung is smaller than the right lung. The extra room on the left side gives room for your heart.

  2. The energy system Our bodies need a supply of energy to enable it ...

    only lasts for 3-8 seconds, but in the bright side is renewed in the ratio of 1:6. The PC system is very important in high intensity activities with rest periods such as weightlifting or doing the 40 m. Application to sport A variety of sports utilise the PC system, this

  1. Exercise health and lifestyle

    And also taking part in exercise reduces the risk of suffering serious illnesses such as a stroke which is gained from high blood pressure. Coronary heart disease This is the leading cause of death in the western world. One third of all deaths are associated with CHD.

  2. Biological Chemicals and Their Role in Sport

    The most common lipid, a triglyceride, in nature looks like this, http://www.oliveoilsource.com/images/triglyceride.jpg 13th October 2006 It is made up of a glycerol which has the formula, C3H8O3 and 3 fatty acids. As previously discussed in carbohydrates, for the 3 fatty acids to attach to the glycerol a condensation reaction needs to occur.

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