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

The Importance of Being The Right Size.

Extracts from this document...

Introduction

The Importance of Being The Right Size 'The higher organisms are not larger than the lower because they are more complicated. They are more complicated because they are larger.' Hyung-woo (Shane) Cho L6GW Most people will be most likely to believe that the higher organisms, such as, animals, are larger because they are more complicated. However, actually, the higher organisms are complicated because they are larger. In other words, they have to be complicated in order to be large. Then why do they have to be complicated? And why do they want to get bigger? Simply, the higher organisms are more complicated because they need more organisms and support from their body itself, to keep their large sized body. All the living things have their own features to adapt their living habitats. Complicated mechanisms and large sized body are included in these features as well. The feature that is linked with the size of a living organism is surface area and the gas exchange. To get the energy to continue their lives organisms need to do respiration. Gaseous exchange is necessary for this, for respiration oxygen is taken into their body, and carbon dioxide are released out to the atmosphere. ...read more.

Middle

A thin, flat shape, such as that of the leaves of plants; the fronds of seaweed; or the body of a flatworm, have a large surface area-to-volume ratio and therefore their gas exchange is potentially extremely efficient. Flat shape also increases the surface area, the protozoan such as flatworm has a flat shape so that all the cells will be exposed and get enough oxygen. Tube shape also increases surface area as well, which helps to increase the rate of gas diffusion. This is why organisms like earthworms are able to respire through their skins. Shape 1 x 1 x 1 2 x 2 x 2 20 x 1 x 0.5 (flat, eg leave) 40 x 0.5 x 0.5 (tube shaped, eg earthworm) Surface Area 6 cm� 24 cm� 61 cm� 80.5 cm� Volume 1 cm� 8 cm� 10 cm� 10 cm� SA : Vol. 6 : 1 3 : 1 6.1 : 1 8.05 : 1 Many larger organisms have specialized sites of exchange, as they want to satisfy the demand of oxygen. The lung specialized organ for animals such as human. ...read more.

Conclusion

The higher organisms can avoid being eaten, eat more things, move longer distances to new food sources or more favourable environment, and reduce heat loss, if they have larger body. Larger body is suitable for keeping temperature, because if they have small body, it will have more surface area that will cause more heat loss from the surface. Small organisms such as amoeba does not need organs such as lungs because it is very small, therefore it has larger surface area compared to its volume, so that it can respire through its surface. Organisms such as leaves of a plant, flatworm, and earthworm have flat or tube shape, which is also a way to increase the surface area to allow more diffusion of gas. Bigger organisms get more complicated because they need more organs and mechanisms to support their body. They need much amount of gas exchange, and because their surface area is less compared to their volume, they need specialized sites for exchange, e.g. lungs and roots. Higher organisms also have good transport system to produce good diffusion gradient for allowing more gas exchange. Also, some organisms which are very heavy, have got much thicker legs to enable themselves to support their body. ...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 Energy, Respiration & the Environment 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 Energy, Respiration & the Environment essays

  1. Marked by a teacher

    Effect of nitrate concentration on the growth of Duckweeds

    5 star(s)

    been affected, This is because not as much water entered the plant cells, so in more concentrated solution it would have led to dehydration of the cells. Therefore less growth of fronds takes place. Another major limitation of the experiment was the growth of algae.

  2. Marked by a teacher

    Home Economics - Why is nutrition important to sports people?

    5 star(s)

    Most foods do not have high protein contents - raw meats and fish contain a maximum of 20% of protein by mass. Athletes involved in endurance training (such as rowing) need 1.2-1.4g protein per kg of body weight, each day. For a 65kg person this would be 78-91kg protein daily.

  1. Marked by a teacher

    Investigation on the size of Limpets.

    5 star(s)

    Larger limpets have a lower surface area : body volume ratio thereby reducing the rate of water loss. Species living at the bottom of the shore (sublittoral zone) such as the Patella aspera haven't adapted in this manner, as

  2. The Pancreas is a large gland that forms part of the Endocrine System, but ...

    - I waited until the contents of the test tube became clear, stopped the clock and noted the time. Step 6 - I will repeat steps 1 - 5 for Samples B, C and D *Modification - Adding the Iodine produces the Blue colour mentioned on the task sheet, however

  1. the effect of bile concentration on the activity of the enzyme lipase during the ...

    Eventually, increasing the concentration of the bile salts will have very little effect on the rate of reaction as the enzyme lipase is already working at its optimum, subsequently other limiting factors such as temperature and pH will be affecting the enzymes activity other than increasing the surface area of the lipid molecules.

  2. Investigate the effect of bile salt concentration on the digestion of milk by the ...

    Change in pH after 1 minute (2) Change in pH after 1 minute (3) Average Average rate of reaction s-1 0 -0.2 0.5 0.4 0.23 0.38 1 0.9 0.7 0.8 0.80 0.77 2 1.1 1 0.8 0.97 0.92 3 1.3 1.2 1.5 1.33 1.34 4 1.1 0.3 0.2 0.53 0.34 5 1.3 1 0.7 1.00 0.90 A

  1. Why the Body Needs Energy? Every living cell within the ...

    and nutrients to pass through along with a large amount of water, so that the solution can dissolve in it, which then filters out through the capillary wall and baths the body tissues therefore the liquid is called interstitial fluid.

  2. The Homeostatic Mechanisms

    The secretion of adrenalin causes increased heart rate as it stimulates the S-A node to work faster. When the panic is over and the level of adrenaline in the body drops, the parasympathetic nervous system becomes active and the homeostatic controls go back to normal.

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