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

Discuss the Biological Importance of Water

Extracts from this document...

Introduction

Discuss the biological importance of water Water is a molecule with the formula H2O. There are two hydrogen atoms covalently bonded to one oxygen atom. The boiling point of water is 373 K and the melting point is 273 K, making water a liquid at room temperature. It is tasteless, colourless and odourless, yet many substances can dissolve in water meaning it has some important roles. It is essential for the proper functioning of the human body, plant life and the environment. Water is essential for the life processes in animals to take place effectively. The human body is made up of 75% water, containing 42 litres on average. Water is excreted through sweat, urine, faeces and water vapour in breath. Sweating is an important duty that every human body carries out. Water is released onto the skin which evaporates using the thermal energy of the body. The water can gain this energy easily and evaporate, cooling the body down and helping maintain a constant body temperature. ...read more.

Middle

Oxygen and carbon dioxide can dissolve in water, which provides sea creatures with oxygen to respire and live in deep oceans. The water is also transparent meaning that the suns rays can reach aquatic plants in the ocean enabling them to undergo photosynthesis. Water is essential in the digestion process. Enzymes are dissolved in water and produced in the mouth and stomach which break down the food and enable the nutrients to be used. The nutrients are absorbed from the villi in the small intestine into the blood stream where they are transported and used by the body. The blood the nutrients are transported is made up of 55% water. The blood plasma contains proteins, salts and other nutrients dissolved in the water. Many other substances also dissolve in the blood and are transported around the body to where they are needed, for example oxygen and carbon dioxide. Oxygen is dissolved into the blood from the alveoli in the lungs. ...read more.

Conclusion

In plants, osmosis also enables the cells to remain turgid and for the plants to remain upright. Water is absorbed by the roots of plants and it travels up the xylem to the leaves where it is used for photosynthesis to enable the plant to growth. The water can be absorbed readily by the roots as they have a large surface area. Water has great surface tension, due to the hydrogen bonds, enabling it to travel up the stem of the plant in the xylem vessels. The water evaporates from the leaves stomata, and as it does so more water is pulled up the xylem and up into the roots due to the surface tension. The hydrogen bonds between the water molecules hold the molecules together and provide the surface tension, allowing pond skaters to survive. Overall, water has very unique properties which make it ideal for the uses of it. No other molecule could be designed, which would improve water, as it is perfect for this world. ?? ?? ?? ?? Joelle Pike ...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 Molecules & Cells section.

Found what you're looking for?

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

Here's what a teacher thought of this essay


**

The material covered in this essay is generally well written, although slightly confused in places, but there are some big omissions that need including in order to score a higher mark. Because the introduction is so long, and there is a large paragraph about cystic fibrosis the essay seems long enough, but actually when these parts are removed the main bulk of the essay is quite brief.

Student needs to cover:

- Latent heat of vaporisation
- Specific heat capacity
- Structural (e.g. maintaining pressure in the eye / turgor in plant cells)

Marked by teacher Rebecca Lewis 24/09/2012

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 Molecules & Cells essays

  1. Marked by a teacher

    Investigating respiration of maggots

    5 star(s)

    This is because the rate of respiration is dependent on the mass of the maggots, so therefore I must know the exact mass of the maggots. I will then be able to calculate the volume of oxygen produced per minute per gram.

  2. Investigation of the effect of adding different concentrations of NaCl to an enzyme-substrate (amylase-starch) ...

    Amount of NaCl in solution (cm�) Number of iodine drops added at 10 second intervals Time taken for solution to change colour from orange to blue/black (seconds) 0.0 51 510.0 1.0 9 90.0 0.8 10 99.5 0.6 11 110.0 0.4 12 120.0 0.2 22 220.5 Third Run Table to show change in time taken for a

  1. An experiment to find of the isotonic point of root vegetables cells in contents ...

    The net movement of water was greater out of the cell than into to it. This showed me that the root vegetable cylinder was placed in a hypertonic solution. Due to this the isotonic solution would be less concentrated, as this would me that less water is leaving the root vegetable.

  2. The Importance of Biological Molecules.

    Receptors-enables hormones, nerve transmitters to pass between specific cells. 5. Recognition sites-identifies cells. 6. Adhesion sites-helps some cells stick together. 7. Enzymes-speeds up chemical reactions at the edge of membrane." Ribonuclease is an enzyme which hydrolyses ribonucleic acid. This enzyme breaks RNA into smaller components.

  1. Type - 1 Hypersensitivity Reaction

    Discussion There is much evidence and data made available via scientific papers in journals, which, indicates that allergens are specific antigens, which are capable of eliciting an immune response, by causing the mast cells to release biological active molecules such as histamine.

  2. Affect of sucrose concentration on the rate of respiration.

    Here is the equation for anaerobic respiration: Enzymes in cytoplasm (Zymase complex) Glucose -----------------> ethanol + carbon dioxide +energy C6H12O6 2C2H5OH CO2 210 Kj/mole There is 2ATP from each respired glucose molecule - in aerobic there is 38ATP. Explanation of Glycolysis ------ Glycolysis is a nine step process, with carbohydrate

  1. An Experiment to investigate the factors that affect the Power Output of a solar ...

    In this form, silicon is a poor conductor. However, impurities can be added to it to alter this characteristic. When energy is added, in the form of light, a few electrons break free of their bonds and leave their atoms, leaving a hole behind.

  2. Acid Hydrolysis of Polysaccharides.

    Glycogen is a water soluble molecule that is formed around a protein core, of a molecule called glycogenin. Radiating out from the centre are polysaccharide chains that bifurcate. The total molecule is therefore spherical in appearance, a sort of 'hairy sphere'.

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