PHOTOSYNTHESIS

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PHOTOSYNTHESIS

process by which light energy is used to make glucose

carried out by all organisms in the Plant kingdom as well as algae in Protista kingdom

its a reduction reaction bc carbon in the carbon dioxide is gaining electrons from the hydrogen in water

STRUCTURE OF THE CHLOROPLAST

organelle enclosed by a double membrane

consists grana (consisting of layers of membranes called thylakoids) where light dependent reactions occur and stroma where the calvin cycle where light independent reactions occurs

LIGHT AND PHOTOSYNTHETIC PIGMENTS

photosynthetic pigments absorb light energy and use it to carry out photosynthesis

substances that absorb light in the visible spectrum are called pigments

chlorophyll a is the green photosynthetic pigment that can participate directly in light reaction

antennae (accessory pigments) assist in photosynthesis by passing on or capturing photons of light to chlorophyll which expands the range of light that can be used to produce sugar

includes chlorophyll b, cartenoids (yellow, red, and orange responsible for color of carrots) and phycobilins (red found in red algae n deep ocean where there is little light)

red and blue light are absorbed and yellow and orange are reflected

ONLY LIGHT THAT IS ABSORBED CAN BE USED TO POWER THE MAKING OF SUGAR

LIGHT-DEPENDENT AND LIGHT-INDEPENDENT

2 main processes of photosynthesis: light-dependent reactions and light-independent reactions aka dark reactions

BOTH OCCUR ONLY WHEN THERE IS LIGHT

function of light-dependent reactions: produce ATP energy

function of light-independent reactions: produce sugar

Light Dependent

occur in grana of chloroplasts within specialized membranes called thylakoids

hundred of light-absorbing complexes called photosystems