Excretion

• What gases can be both reactants and waste products in plants?

  Oxygen and carbon dioxide
• How does light intensity affect plants?

  It affects the waste products within plants
• What happens to the rate of photosynthesis during the day?


  It is higher than the rate of respiration
• What is released more during the day, oxygen or carbon dioxide?

  More oxygen is released
• What is the net effect of photosynthesis during the day?

  Oxygen is in excess and a waste product
• What occurs during the night in plants?

  Only respiration occurs, no photosynthesis
• What gas is used in respiration at night?

  Oxygen
• What is produced during respiration at night?

  Carbon dioxide is produced
• What is the net effect of gas exchange at night?

  Carbon dioxide is in excess and a waste product
• Through which structures do gases exit the plant?

  Through the stomata
• Why is the excretion of gases in plants not considered an active process?

  It occurs via diffusion
• The kidneys remove urea from the blood, adjust ion levels and water content in the blood. The body reabsorbs useful things, and the waste is urine
• The lungs excrete carbon dioxide
• The skin excretes excess salt from the body via sweat