exchange and transport in animals Flashcards
What 6 things do animals exchange?
Oxygen, carbon dioxide, water, food molecules, mineral ions and urea
Where does the exchange take place?
Cell membrane
What are the properties of unicellular organisms?
Large surface area to volume ratio therefore don’t have specialised transport systems
What are the transport systems in animals?
Blood and circulatory system
What are the transport systems in plants?
- Xylem - water & mineral ions from roots to shoots
- Phloem - sugars & amino acids
What are the exchange surfaces in animals?
- Lungs & alveoli - gas exchange
- Small intestines & villi - absorption of digested food
What does the blood consist of?
RBC, WBC, platelets and plasma
Features of arteries?
- Carry oxygenated blood at high pressure, fast, away from heart
- Thick, muscular walls
- Narrow lumen
Key features of veins?
- Carry deoxygenated blood at low pressure, slow towards heart
- Thin walls
- Thick lumen
- Valves
Features of capillaries?
- Carry oxygenated & deoxygenated blood at low pressure, slow within tissues
- Walls are one cell thick and ‘leaky’
How is the circulatory system split?
- Pulmonary circuit - heart & lungs
- Systemic circuit - heart & body
Explain how blood flows in and out of heart.
Deoxygenated blood flows through vena cava, into right atrium. It contracts & goes through tricuspid valve into right ventricle. It contracts & pushed into pulmonary artery. It travels to the lungs.
Oxygenated blood returns via pulmonary vein to left atrium. It contracts & goes through bicuspid valve into left ventricle. It contracts & forced out through aorta. It travels around whole body.
What type of respiration is cellular?
Exothermic
What is aerobic respiration?
Requires oxygen, complete breakdown of glucose, CO2 & H2O are waste products
What is anaerobic respiration?
Insufficient oxygen, incomplete breakdown of glucose, lactic acid is a waste product
What is ‘oxygen debt?’
The amount of oxygen needed to break down the lactic acid that has built up
How do you calculate cardiac output?
Stroke volume x heart rate
What is the method for measuring the rate of respiration?
- Collect tube with soda lime, held in place with cotton wool.
- Collect small organisms in a weighing boat.
- Shake organisms out of container & into tube
- Insert bung & capillary tube. Set up control tube.
- Hold a beaker of coloured liquid to ends of the capillary tubes
- Mark position of coloured liquid in tube and time for five minutes.
- Mark position of coloured liquid again, & measure distance it has travelled.
