photosynthesis Flashcards
what is the importance of photosynthesis?
almost all living organisms owe their continued existence to photosynthesis. the energy we use has been captured by photosynthesis from sunlight. it also produces the oxygen we breathe by releasing it from water molecules.
what is photosynthesis?
photosynthesis is the process in which light energy is used in the synthesis of organic molecules, such as glucose. like respiration, photosynthesis is a series of enzyme catalysed reactions and therefore any factor that effects enzyme activity will affect the rate of photosynthesis.
where does photosynthesis take place?
in the chloroplasts of cells in the leaves and other green parts of the plant
the reactions of photosynthesis involve the __________ of _____ by the pigment ___________
absorption, light, chlorophyll
what other organisms can photosynthesise?
algae and cyanobacteria are also able to photosynthesise to make food
what do photosynthesising organisms do in addition to photosynthesis?
these organisms then respire some of the food they make to provide them with energy for metabolic processes. excess food can be stored or used to make other substances such as cellulose, proteins, lipids etc. which are used for growth.
what is the equation for photosynthesis?
carbon dioxide + water → glucose + oxygen
6CO2 + 6H2O → C6H12O6 + 6O2
(light above the arrow, chlorophyll below the arrow)
what are the two distinct stages of the reactions of photosynthesis?
the light dependent reactions and the light independent reactions
draw and label the structure of a chloroplast
see diagram
what occurs in the thylakoid?
light dependent reaction occurs in thylakoids. chlorophyll molecules in thylakoid membrane absorb light energy. ETC is also embedded in thylakoid membrane.
what are 4 parts of the chlorophyll and their functions/adaptations?
grana (thylakoid sacks) increase efficiency of LDR by capturing most of the light energy that enters the chloroplast.
stroma contains enzymes required for LIR.
outer membrane controls movement of substances into and out of the chloroplast.
starch grains store excess carbohydrate made in photosynthesis (LIR).
