respiration Archives

Learning objectives define aerobic respiration state the word equation for aerobic respiration list uses of energy in the body list uses of energy in the body state the word equations for anaerobic respiration in plants and animals describe the production and effects of lactic acids on muscles during exercise Definition is the oxidation of food substances eg carbohydrates with the release of energy. it occurs in living cells. Uses of energy maintenance of constant body temperature active transport making protein molecules muscle contraction cell division transmitting nerve impulses Types of Respiration Aerobic respiration Anaerobic respiration Aerobic Respiration breakdown of glucose to carbon dioxide and water to release large amounts of energy in the presence of oxygen; C6H12O6 + 6O2 → 6CO2 + 6H2O Anaerobic Respiration oxygen is not required. small amounts of energy is released. lactic acid produced in mammals; ethanol and carbon dioxide produced in yeast Alcoholic Fermentation- in yeast cells Glucose → ethanol + CO2 + energy Lactate/acidic Fermentation- eg in muscle cells Glucose → lactic acid Differences between anaerobic and anaerobic respiration Aerobic Anaerobic occurs in mitochondrion in cytoplasm large amounts of energy released small amounts of energy released water + carbon dioxide lactic acid or CO2 + ethanol require oxygen oxygen not required HUMAN GAS EXCHANGE The organs for gaseous exchange are the lungs found inside the ribcage. Gases exchanged are oxygen and carbon dioxide. Lungs Air Passage Nasal Passage the anterior most part which opens through external nostrils to the outside it has hairs lining the nasal cavity- filter the air and trap large particles moisture ie keeps the hairs moist blood capillaries warm the incoming air. Trachea trachea splits into two bronchi-one goes to each lung. It contains cartilage rings which keep it open and prevent it from collapsing is lined with a mucus layer and cilia mucus trap pathogens like bacteria and dust particles cilia move in a sweeping motion to keep the air passage clean The bronchi split further into bronchioles the bronchioles finally end at alveoli, where gas exchange take place The process of diffusion there will be more oxygen inside the alveoli than there is in the surrounding blood capillaries. oxygen diffuses from the air sacs into the blood capillaries it will be absorbed by red blood cells There will be more carbon dioxide inside the blood capillaries than there is in air sacs carbon dioxide will diffuse from the blood into the air sacs Differences between inhaled and exhaled air Inhaled air % Exhaled air % Oxygen 20 16 Carbon dioxide 0,04 4 Nitrogen 79 79 Water vapor varies saturated Oxygen is used during respiration. Carbon dioxide is the product of respiration. Nitrogen is not used directly by the body water vapor is saturated because it is a product of respiration TEST FOR CARBON DIOXIDE lime water changes from clear to milky in the presence of carbon dioxide. Bicarbonate indicator changes from red to yellow in the presence of carbon dioxide. Breathing Mechanism Inspiration external intercostal muscle contract internal intercostal muscle relax ribs moves upwards and outwards diaphragm contracts and flattens volume of thorax decreases air flows into lungs Expiration external intercostal muscle relax internal intercostal muscle contract ribs moves downwards and inwards diaphragm relaxes and arches upwards volume of thorax decreases air flows out lungs The Alveoli gaseous exchange takes place between the air sacs and the blood Gas Exchange between the alveolar space and the blood the O2 from the air sac diffuse into the moist layer-increases the concentration of O2 it diffuses through the alveolar epithelium into the blood capillaries Blood continuous circulation maintaining the lower conc O2 in the blood capillaries, so it diffuses into blood capillaries O2 combines with hemoglobin in the red blood cells Oxygenated blood is transported out of the lungs Diffussion across the alvoeli is enhanced by; thin- shorter distance to diffuse moist- allow gases to dissolve large surface area have a concentration gradient across surface-maintained by movement of air and transport ability of blood to carry oxygen and carbon dioxide

Tag: respiration

Respiration

Glycolysis

The Krebs Cycle

Oxidative Phosphorylation