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Year 9 Science 2013. Control & Coordination Part 1 The Respiratory System. Gas Exchange. Oxygen and carbon dioxide need to be exchanged with the environment for ___________and _____________. Diffusion.
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Year 9Science 2013 Control & Coordination Part 1 The Respiratory System
Gas Exchange Oxygen and carbon dioxide need to be exchanged with the environment for ___________and _____________
Diffusion The process of gas exchange is always by _____________between the external and internal environment of the organism.
Surface Area: Volume For single-celled and small organisms this is not a problem because of their high ___________to __________ratio.
Multicellular Organisms Large organisms rely on specialised __________surfaces.
Features of Respiratory Surfaces Large____________ ______, _______and easily penetrable surface. Adequate____________ Efficient transport of carrier fluid_________) across respiratory surface.
Mammalian Respiratory System Is composed of: • Lungs • Respiratory passages • ___________ • ___________ • ____________ • _____________ • _____________
Alveoli The site of________________ Increases the surface area for gas exchange. http://www.bmu.unimelb.edu.au/examples/gasxlung/
Breathing Contraction & relaxation of the __________muscle results in changes in pressure within the lung cavity, forcing air in & out.
Epiglottis The ___________prevents food from travelling down the trachea and blocking the passage of air.
Gas exchange relies on diffusion, therefore ______________gradients need to be maintained.
For oxygen to continually diffuse into capillaries around alveoli, oxygen needs to be transported ___________from the site
Respiratory pigments such as ___________carry oxygen in the blood from lungs and release oxygen into cells.
Rhythmic pumping of the __________ensures continuous flow of blood along capillaries surrounding the alveoli.