Gaseous Exchange in Animal PDF

GASEOUS EXCHANGE IN ANIMAL Norfarahin Norwen | [email protected] Aquila Watercolour Illustrator Finch Fight Illustrator...

GASEOUS EXCHANGE IN ANIMAL Norfarahin Norwen | [email protected] Aquila Watercolour Illustrator Finch Fight Illustrator Mother Daughter Illustrator LEARNING OBJECTIVES To explain the gaseous exchange in human To explain the gaseous exchange in invertebrate and vertebrate  Human respiratory structure  Breathing mechanism of human Exhalation Inhalation External intercostals External intercostals muscles relax, internal muscles contract, intercostals muscle internal intercostals contract. –rib cage muscle relax. –rib moved lowered and cage moved up move inwards toward the front Diaphragm muscles Diaphragm muscles relaxes and curves up contract and flatten Volume of the Volume of the thoracic cavity thoracic cavity decreases increases Higher pressure in Higher atmospheric thoracic cavity pushes pressure pushes air air out of the lungs into the lungs Human respiratory structure Main organ; lung Trachea branches into two main bronchus/bronchi. Further into smaller tubes; bronchioles. Each ends in a cluster of microscopic air sacs; alveolus/alveoli respiratory structure where the gas exchange between the blood and air occurs by simple diffusion Alveolus: Site for Gaseous Exchange Structural adaptations: Small size and high number present –for larger surface area Moist wall –allows respiratory gases to dissolve easily Thin wall –for quick and easy diffusion of gases Rich supplied with blood capillaries –to increase the rate of diffusion and the rate of the transportation of gases  Exchange of O₂ and CO₂ -alveoli and blood capillary During inhalation, partial pressure of O₂ is higher in alveoli than blood capillary. O₂ diffuses into blood capillary PCO₂ is higher in blood capillary than alveoli. So, CO₂ moves into alveoli in opposite direction and gets exhaled out  Exchange of O₂ and CO₂ -blood capillary and tissues Partial pressure of O₂ is higher in blood capillary than tissues. O₂ gets release into tissues PCO₂ is higher in tissue than in blood capillary. So, CO₂ diffused in opposite direction into blood  Transport of Oxygen in Human 98% O2 in blood transported by haemoglobin (Hb) in the form of oxyhaemoglobin (HBO₂) Another 2% dissolved in plasma, transported by it Transport of Carbon dioxide in Human 7% of the CO₂ dissolved in the plasma 23% of the CO₂ combines with haemoglobin (Hb) forming carbaminohaemoglobin (HbCO₂). It then breaks down, releasing CO₂ into the alveoli 70% of excess CO₂ diffuses into red blood cells reacting with water (H₂O) becoming carbonic acid (H₂CO₃). It then moving into the plasma while dissolved CO₂ diffuses into the alveolar air space The Respiratory Control System Respiratory controls centers: Medulla Oblongata –controls respiration to cause breathing to occur by sending signals to the muscles of respiratory structure Also controls the reflexes for nonrespiratory air movements Pons –controls the rate or speed of breathing Regulation of Breathing is a form of negative feedback. The goal is to keep pH blood within normal range. Chemoreceptor detect changes in chemical composition of blood and send information to the brain. An increase of CO2 concentration leads to a decrease in the blood pH, due to the production of H+ ions from carbonic acid. In response, the respiratory center in the medulla sends nervous impulses → external intercostal muscles and the diaphragm, to allow respiratory muscles contract and relax faster. Breathing and ventilation rate increase causing more O2 to be inhaled and the O2 concentrations returns to normal. As excess CO2 is eliminated from the body, the CO2 concentration and blood pH return to normal level. Respiratory Problems 1. Pneumonia lung(s) infection from bacteria / viruses / fungi, causes alveoli fill up with fluid or pus Symptom: mild to serious cough with/without mucus fever, shaking chills Trouble/rapid in breathing, rapid pulse Treatment: can be prevented by vaccines. Can be treat by antibiotic, viral, or fungal medicines, If get worse? Antibiotics given through intravenous line and oxygen therapy Respiratory Problems 2. COPD: Emphysema long-term exposure to airbone irritants damaging air sacs, inner walls become weaken and rupture. It then affect amount of O₂ → bloodstream Symptom: long-termed coughing shortness of breath coughing with mucus wheezing, ongoing fatigue, trouble sleeping chest tightness Treatment: stop smoking, avoid secondhand smoke and air pollutant, wear protection from chemical fumes, varnish, paint or dust Respiratory Problems 3. COPD: Chronic Bronchitis exposure to cigarette smoking, air pollution of dust or toxic gases inflamed the lung airways, destroy cilia; bronchi cause sticky mucus to build up in it Symptom: shortness of breath Coughs for at least 3 months wheezing chest pain tiredness Treatment: lifestyle changes and medication such bronchodilators to relax air passages, steroids to lessen the swelling. Oxygen therapy, specialized rehab programme, lung transplant Respiratory Problems 4. Asthma Major noncommunicable disease (NCD) that makes airways narrow, swell, and blocked due to producing of extra mucus Symptom: breathing difficulty shortness of breath coughing whistling, wheezing trouble sleeping Treatment: inhaled medication, avoid asthma triggers such airborne substances, air- conditions cold and dry Respiratory Problems 5. Tuberculosis contagious infection of Mycobacterium tuberculosis that attacks lungs, can also spread to other part of human body. Start with Primary, Latent, Active to Active outside lungs Symptom: breathing difficulty, chest pain fever, chills cough last more than 3 weeks coughing up blood Night sweats Loss appetite, weigh loss Treatment: most cured by antibiotics, medications for at least 6 to 9 months  Invertebrate Circulatory System Roundworm Phylum Porifera Phylum Cnidaria Phylum Nematoda  The blood flows This system has freely through vessels that cavities since there conduct blood are NO vessels to throughout the conduct the blood body *annelids & *mollucs & arthropods vertebrates Gaseous Exchange in INVERTEBRATE respiration Skin-breathing Movement of O2 and CO2 across moist respiratory surfaces takes place entirely by diffusion Survive for extended periods only in damp or aquatic habitat  Tracheal systems Air enters the spiracles; small holes located at the thorax and abdomen Air is distributed through the body of the organisms via trachea and tracheoles that come into close contact with the organisms' cells  Vertebrate Circulatory System All vertebrates have a closed cardiovascular system Vertebrate heart Two different circulatory pathways in vertebrates; Atrial chamber(s) of heart receive Single-loop blood from general circulation heart only pumps blood to gills Ventricle chamber(s) of heart pump Two-circuits blood out through blood vessels Pulmonary circuit - heart pumps blood to the lungs Vertebrate vessels Arteries carry blood away from heart Systemic circuit - heart pumps blood to all parts Arterioles lead to capillaries of the body except for the lungs Capillaries exchange materials with tissue fluid Venules lead to veins Veins return blood to heart Fishes single loop Amphibians, Reptiles double loop Heart with single atrium and Two atria and single ventricle pumps a single ventricle blood in the pulmonary circuit to the lungs enriched blood with oxygen when it leaves gills Also pumps blood in the systemic circuit to the rest of the body O2 -rich and O2 -poor blood enter the single ventricle, it is kept separated O2-poor blood is pumped firstly out of the ventricle into the lungs before O2- rich blood enters and is pumped into the systemic circuit Birds and Mammals Two atria and two ventricles in the heart and there’s complete separation of the pulmonary and systemic circuits Right ventricle pumps blood under pressure to the lungs, and the larger left ventricle pumps blood under pressure to the rest of the body Gaseous Exchange in VERTEBRATE respiration A fish simply open its mouth and let water flow past its gills Each gill arch has two rows of gills filaments, composed of flattened plates called lamellae Blood flowing through capillaries within the lamellae, picks up oxygen from the water Counter current exchanges mechanisms; water flow over the gills in one direction while blood flows in opposite direction through capillaries Mouth By vascular bucco-pharyngeal. Occur while the frog is not submerged in water Skin Thin, permeable to water and kept moist as it covered by mucous lining. Entirely dependent on respiration through the skin when they are underwater. Lungs Consist of a pair of thin-walled sacs connected to the mouth through an opening called glottis. The membranes of the lungs are thin, moist and covered by a network of capillaries. Use their throats, nostrils and mouths together to bring in and expel gases. Bird’s respiratory system consists of paired lungs with connected to two air sacs. Passage of air through the entire system requires two cycles of inhalation and exhalation cycle, before it is fully used and exhaled out of the body. 1st inhalation: Fresh air travels through trachea, which splits into left and right primary bronchi. Some air enters the lungs where gas exchange occurs while the remaining air fills the posterior air sacs 1st exhalation: Posterior air sacs contract, pushing air into lungs and undergoes gas exchange. *The spent air in the lungs is displaced by the incoming air and flows out the body through the trachea 2nd inhalation: *Fresh air again enters both the posterior sacs and the lungs. Spent air in the lungs is again displaced by incoming air but it cannot exit through trachea because fresh air is flowing inward. Instead, spent air passes through lungs and fills anterior air sacs 2nd exhalation: Anterior air sacs contract, air in the lungs flows out through the trachea, and fresh air in the posterior sacs enters the lungs for gas exchange