There are 2 types of respirations:
How do we study Respiration?
Respiration in bio → refers to cellular respiration → which is the release of energy when cells break down glucose in the presence of oxygen. → this is different from Breathing which is the process by which air moves in and out of the lungs.
Aerobic respiration → oxygen is consumed while CO2 water and energy are released. some energy is released in the form of heat. → we can show an organism consumes oxygen and gives out CO2 and heat, it is respiring aerobically.
anaerobic respiration in humans - is difficult to detect.
- because it does not require the consumption of oxygen and may not give off co2 as a product
however micro-organisms like yeast - do give off CO2 when respiring anaerobically. thus if we can show that yeast gives off CO2 in the absence of oxygen, we can say it respires anaerobically.
Definition
Gas exchange is the exchange of gasses between an organism and the environment #BiologyDefinitions
unicellular organisms such as amoeba have a large surface area to volume ratio → such organisms do not require any gas exchange system or oxygen transport mechanisms. → O2 and CO2 can be exchanged efficiently between organism and water by diffusion through the cell membrane.
large animals - fish, amphibians → have smaller surface area to volume ratio. → external surfaces are often thickened for protection and to prevent water loss. → therefore these surfaces are not suitable for gas exchange. they use special organs such as lungs and gills for gas exchange. these organs have enlarged surface areas and thin coverings. More O2 can be absorbed and more CO2 removed from the body per unit time.
Parts of the Human Respiration System
Parts of the Human Respiratory System
Stimulus for Breathing
stimulus for Breathing: High concentration of CO2 in the blood or in alveolar air. NOT lack of Oxygen.
How is oxygen transported around the body
in lungs where oxygen concentration is high - oxygen combines with haemoglobin in RBC to form oxyhaemoglobin. oxygenated blood is transported from lungs to other parts of the body.
When blood passes through organ or tissue, where O2 concentration is low, oxyhaemoglobin will release its oxygen into respiring cells.
Breathing
Effects of Tobacco smoke on human health TBC
Effects of Tobacco Smoke on Human Health
Disease caused by tobacco smoke
Disease caused by Tobacco Smoke
Sample
Suggest why number of deaths from lung cancer in smokers is much greater than it is in non smokers
- cigarette smoke contains carcinogenic substances like tar which increases cancer in lungs as well as death. (add to all diseases page)
Sample
suggest why mothers who smoke during pregnancies are likely to have babies with lower body mass
- carbon monoxide in cigarette smoke binds to haemoglobin in mother’s red blood cells to form carboxyhaemoglobin which prevents RBC from transporting oxygen.
- less oxygen is passed to the foetal blood at the placenta.
- low oxygen levels in foetus reduce ability of cells to release energy thru cellular respiration for cellular growth and development. (add to all diseases page)
Sample
oxygen required after exercise is equal to amt of oxygen debt
- bc same volume is required to repay oxygen debt / break down lactic acid
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