leaves and photosynthesis

photosynthesis

• trait inherited from a green algae ancestor

• converting inorganic CO2 into organic carbon form

• can occur in any tissue that has chloroplasts

photosynthesis formula

carbon dioxide + water = sugar + oxygen

carbon dioxide

• provides carbon for sugar protection

• released when we burn coal and fossil fuels

• greenhouse gas which traps infrared radiation and helps keep plants warm for human life

chlorophyll

• green pigment that absorbs light energy

• absorbs red and blue light

water

used in light reactions

light

provides energy

glucose

produced by sugar

oxygen

a by-product released from plants photosynthesizing

2 types of reactions photosynthesis requries to create sugars

1. light reactions

2. dark reactions

light reaction

• involve chlorophyll for capturing light energy

• require light energy and water for creating energy molecules and oxygen

dark reaction

• involve the enzyme Rubisco

• require carbon dioxide to create glucose

light reaction in chloroplasts

occur in thylacoids that stack up

dark reaction in chloroplasts

occurs in fluid that floats around within the chloroplast “stroma”

primary function of leaves

to conduct photosynthesis which contain vascular tissue, xylem and phloem

solar panels

• designed based on leaves bc they have water conduction and evaporation that cool the solar panels like how evaporation cools the leaf

  • need to cool bc when its too hot, don’t produce electricity as efficiently

• absorb light for energy

mesophyll cells in leaves

• photosynthesis occurs in the palisade mesophyll of leaves

• large concentration of chloroplasts

stomata

• pores in leaves that allow gases to move through, depending on conditions

• on the lower side of leaves, while photosynthesis happens on the upper side

respiration

plants produce small amounts of carbon dioxide that is released back into the atmosphere

temperature and photosynthesis

photosynthesis increases w temperature and then drops off quickly when temperatures get to a damaging point

photoinhibition

• too much light is damaging bc it can cause light and dark reactions to get out of sync

• moving plant in shade to sun right away can cause leaves to get sunburned