2- excretion Flashcards
within plants there is a range of
metabolic reactions taking place producing waste products
waste products of plants
oxygen, carbon dioxide, water, unwanted chemical substances
the amount or intensity of
light affects waste products in plants
during the day when there is sufficient light-
the rate of photosynthesis is higher than the rate of respiration, more oxygen is released than used in respiration, less carbon dioxide is released than used in photosynthesis and so oxygen is in excess and a waste product
during the night when there is insufficient light
there is no photosynthesis only respiration, oxygen is used in respiration and carbon dioxide is produced. no photosynthesis means that no carbon dioxide is used so carbon dioxide is in excess and becomes a waste product
in plants gases exit through the
stomata
the majority of water lost from a plant is
not a waste product of metabolism but instead water that has been drawn up from roots in the transpiration system
plants can break down
molecules into chemical substances no longer required by the plant
chemical waste materials can be stored
in the dying tissue of a plant
the kidneys excrete
urea, water, mineral ions
the lungs excrete
carbon dioxide and water
the skin excretes
mineral ions and water
the liver excretes
breakdown of proteins into amino acids
