photosynthesis Flashcards
word equation
carbon dioxide + water ——-> glucose + oxygen light
symbol equation
6CO₂ + 6H₂O ——-> C₆H₁₂O₆ +6O₂
light
where does photosynthesis take place?
in chloroplasts within palisade cells
what do chloroplasts contain which helps photosynthesis and why?
chlorophyll as it absorbs light
is photosynthesis exothermic or endothermic and why?
endothermic-energy is transferred from the environment to chloroplasts by light
describe the role of energy in photosynthesis
It uses energy to change carbon dioxide and water into glucose and oxygen. Energy is transferred to the chloroplasts from the environment by light.
list 5 ways in which plants use glucose from photosynthesis
-respiration
-used to produce cellulose
-used to produce amino acids
-make lipids to store as oils or fats
-converted to insoluble starch for storage
why is glucose needed for respiration?
it provides energy
how is glucose used in making cellulose?
glucose is converted into cellulose for making strong plant walls
how is glucose used in making amino acids?
glucose is combined with nitrate ions to make amino acids, which are then made into proteins
why is glucose stored as oils or fats?
glucose is turned into lipids for storing in seeds
why is glucose stored as starch?
so it is ready to use when photosynthesis isn’t happening
describe what happens in photosynthesis
Energy is transferred to the chloroplasts in the plant from the environment by light. The light is used as energy to change carbon dioxide and water into glucose.
what is photosynthesis?
an endothermic reaction by which plants synthesise glucose using light energy
6 leaf adaptations which maximise rate of photosynthesis
-broad leaves: maximise surface area
-thin leaves: short diffusion distance
-chlorophyll present: trap light energy
-veins: transport water to leaves via xylem, remove products of photosynthesis via phloem
-air spaces: allow carbon dioxide to enter and oxygen to exit
-guard cells: control opening of stomata
