exchange and transport in plants

• Why is it necessary to transport substances into organisms?

  To support vital life processes
• What do plants need to take in during photosynthesis?

  Carbon dioxide and dissolved nutrients
• What is the role of the kidney in animals?

  To remove waste like urea and excess ions
• What happens if excess urea is not removed from the body?

  It builds up and becomes toxic
• What condition can excess carbon dioxide in the blood cause?

  Acidosis
• What do specialised exchange surfaces allow?

  Efficient transport of substances
• What is a key feature of exchange surfaces?

  They have a large surface area
• What do root hair cells do?

  Take up water and nutrients from soil
• How do the walls of nephrons aid in their function?

  They have thin walls and a large surface area
• What is the function of alveoli in the lungs?

  To transfer oxygen to blood and carbon dioxide to lungs
• What are villi in the small intestine responsible for?

  Absorbing digested food into the bloodstream
• How do fish gills facilitate gas exchange?

  Water flows over gills while blood flows in the opposite direction
• What role do guard cells play in plants?

  They control the size of stomata
• What are the adaptations of exchange surfaces and their purposes?

  • Large surface area: Increases diffusion rate
  • Thin membrane: Shortens diffusion pathway
  • Efficient blood supply/ventilation: Maintains steep concentration gradient
• What is the composition of blood?

  Plasma, red blood cells, white blood cells, platelets
• What is the function of plasma in blood?

  It carries blood components and nutrients
• What is the primary function of red blood cells?

  To carry oxygen from lungs to cells
• How does the shape of red blood cells aid their function?

  Their biconcave shape provides a large surface area
• What is the role of haemoglobin in red blood cells?

  It binds to oxygen to form oxyhaemoglobin
• What is the function of white blood cells?

  To defend against pathogens
• What do platelets do in the blood?

  Help form blood clots at wound sites
• What is the function of arteries?

  To carry blood away from the heart
• How do veins differ from arteries?

  Veins have valves and a wider lumen
• What is the role of capillaries?

  To allow substances to move between blood and cells
• What is the function of the heart in the circulatory system?

  To pump blood around the body
• What is the double circulatory system?

  Two circuits for blood flow: lungs and body
• What happens to deoxygenated blood in the heart?

  It flows into the right atrium and ventricle
• What is the role of valves in the heart?

  To prevent blood from flowing backwards
• What is the function of the pacemaker in the heart?

  To control the heart's natural resting rate
• What is the purpose of an artificial pacemaker?

  To regulate an irregular heartbeat
• What is respiration?

  Process of transferring energy from glucose
• What type of reaction is respiration?

  Exothermic
• What are the two types of respiration?

  Aerobic and anaerobic respiration
• What is the equation for aerobic respiration?

  $C_6H_{12}O_6 +$$O_2 \rightarrow CO_2 +$$H_2O$
• What happens during anaerobic respiration in animals?

  Glucose is converted to lactic acid
• What is fermentation in plants and yeast?

  Glucose is converted to ethanol and carbon dioxide
• What is the purpose of the respirometer?

  To measure the rate of respiration
• What is the equation for cardiac output?

  Cardiac output = stroke volume × heart rate
• What is stroke volume?

  The volume of blood expelled per contraction
• What is heart rate?

  The number of heartbeats per minute