Tuesday, 28 April 2015

2.50 understand the need for a transport system in multicellular organisms

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Multicellular cells have large volume to surface area ration so diffusion happens too slowly for organism to sustain itself. Therefore, the...

2.49 understand why simple, unicellular organisms can rely on diffusion for movement of substances in and out of the cell

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Unicellular cells have a small volume to surface area ratio making diffusion an effective way to get the substances they require.

2.48 describe experiments to investigate the effect of exercise on breathing in humans.

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Experiment to investigate the effect of exercise on breathing in humans: 1)       Have someone do jumping jacks for a certain amount of t...

2.47 understand the biological consequences of smoking in relation to the lungs and the circulatory system, including coronary heart disease

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Consequences of smoking: ·          Blood clots ·          Cancer ·          Coronary artery disease ·          Decreased ability t...

2.46 explain how alveoli are adapted for gas exchange by diffusion between air in the lungs and blood in capillaries

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Alveoli adaptations: ·          Made of one cell layer: easy for gases to diffuse in and out ·          Spherical: more surface area ...

2.45 understand the role of the intercostal muscles and the diaphragm in ventilation

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Intercostal muscles: Inspiration: ·          The external intercostal muscles contract ·          Causes the rib cage to be lifted up...

2.44 describe the structure of the thorax, including the ribs, intercostal muscles, diaphragm, trachea, bronchi, bronchioles, alveoli and pleural membrane

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The Thorax: ·          Is incased by the rib cage which has intercostal muscles in between the ribs and the diaphragm underneath ·     ...