Download PHOTOSYNTHESIS

What are organelles?

PHOTOSYNTHESIS

Def: The process that uses the sun’s energy to make simple sugars (food energy). These sugars are then converted to complex carbohydrates- starches, and stored.

Photosynthesis takes place inside the cell organelle, chloroplasts, in the leaf of a plant.

The pigments (most commonly, chlorophyll) are in the membrane of the thylakoid discs.

These are what absorb the sunlight.

Chlorophyll absorbs most wavelengths of light except green. Since green is not absorbed, it is reflected.

Some plants stop producing chlorophyll in their leaves in the Fall, so other pigments become visible.

Carbon Dioxide enters the plant leaf through openings called stomata.

Water enters the plants through the roots and travels upward to the leaves.

Once the plant has all three ingredients, a series of chemical reactions take place in the chloroplasts.

So, plants make the food energy (glucose) in the chloroplasts. When they need to break down their own glucose to make ATP, they use another organelle, the Mitochondria.

Cellular Respiration Def: The process by which mitochondria break down food energy molecules (like glucose) to produce a chemical energy molecule called ATP, is known as cellular respiration.

Animals breathe in the oxygen released during Photosynthesis, and when we eat autotrophs, we take in the glucose made….and the starch that was stored.

OXYGEN

GLUCOSE

Photosynthesis

Cellular Respiration

Cellular respiration is also carried out by mitochondria in animal cells. We use food energy and oxygen and create CO2 , water, and ATP (chemical energy)

Cellular Respiration

C6H12O6 + 6O2 → 6CO2 + 6H2O + 36ATP Glucose

Oxygen Gas

Carbon Dioxide

Water

Energy

It is the reverse process of photosynthesis

COMPARING PHOTOSYNTHESIS AND CELLULAR RESPIRATION:

Comparison of Photosynthesis and Cellular Respiration Photosynthesis Food synthesized

Cellular Respiration

Energy from sun stored in glucose

Food broken down Energy in glucose released

Carbon dioxide taken in

Carbon dioxide given off

Oxygen given off

Oxygen taken in

Occurs only in presence of chlorophyll

Occurs in all living cells