Cell Processes The CELL must undergo certain processes in order to ensure the survival of the organism as a whole.

PHOTOSYNTHESIS Autotrophic Process: Plants and plant-like organisms make their energy (glucose) from sunlight. Stored as carbohydrate in their bodies. 6CO2 + 6H2O + sunlight  C6H12O6 + 6O2

Photosynthesis Plants use light energy (sunlight) to combine carbon dioxide (CO2) and water (H2O) to make simple sugars (C6H12O6)

Why is Photosynthesis important? Animals cannot make their own food so they have to rely on other organisms for nutrition. Makes organic molecules (glucose) out of inorganic materials (carbon dioxide and water). It begins all food chains/webs. Thus all life is supported by this process. It also makes oxygen gas!! 4

What is all this “food” (better known as glucose) used for? It can be used by the plant to make energy in the mitochondria It can be stored by the plants in vacuoles It can be eaten by a consumer

Photo-synthesis means "putting together with light." Plants use sunlight to turn water and carbon dioxide into glucose. Glucose is a kind of sugar. Plants use glucose as food for energy and as a building block for growing. Autotrophs make glucose and heterotrophs are consumers of it. 7

What happens during photosynthesis? Chloroplasts in plant cells capture light energy and use that energy to make glucose or “food” Oxygen gas is also released as a by-product in this reaction

Chloroplasts make the sugars! 9

Stoma This opening how plants exchange gases. Check it Stoma This opening how plants exchange gases! Check it! Can you name the two important gases that go in and out of the leaves? Why are the stomata located on the underside of leaves? 10

PHOTOSYNTHESIS Absorbing Light Energy to make chemical energy: glucose! Pigments: Absorb different colors of white light (ROY G BIV) Main pigment: Chlorophyll a Accessory pigments: Chlorophyll b and Carotenoids These pigments absorb all wavelengths (light) BUT green! It is these specific wavelengths that are provide the energy needed to complete photosynthesis

Visible light is only a small part of the electromagnetic spectrum (all forms of light). 12

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Photosynthesis Glucose provides the energy and carbon needed to make other plant materials like wax and proteins. 14

Photosynthesis Glucose provides the energy and carbon needed to make other plant materials like wax and proteins. 15

Photosynthesis Glucose provides the energy and carbon needed to make other plant materials like wax and proteins. 16

Photosynthesis Glucose provides the energy and carbon needed to make other plant materials like wax and proteins. 17

Oxygen and Sugar! 18

PHOTOSYNTHESIS 2 Phases Light-dependent reaction Light-independent reaction Light-dependent: converts light energy into chemical energy; produces ATP molecules to be used to fuel light-independent reaction Light-independent: uses ATP produced to make simple sugars.

PHOTOSYNTHESIS Light-dependent reaction (LIGHT Reaction) Requires light Occurs in chloroplast (in thylakoids) Chlorophyll (thylakoid) traps energy from light Light excites electron (e-) Kicks e- out of chlorophyll to an electron transport chain Electron transport chain: series of proteins in thylakoid membrane Bucket brigade

PHOTOSYNTHESIS Light-dependent reaction (LIGHT Reaction) Energy lost along electron transport chain Lost energy used to recharge ATP from ADP NADPH produced from e- transport chain Stores energy until transfer to stroma Plays important role in light-independent reaction Total byproducts: ATP, NADP, O2

PHOTOSYNTHESIS Light-independent reaction (Dark Reaction) Does not require light Calvin Cycle Occurs in stroma of chloroplast Requires CO2 Uses ATP and NADPH as fuel to run Makes glucose sugar from CO2 and Hydrogen

PHOTOSYNTHESIS What affects photosynthesis? Light intensity: as light increases, rate of photosynthesis increases

PHOTOSYNTHESIS What affects photosynthesis? Carbon Dioxide: As CO2 increases, rate of photosynthesis increases

PHOTOSYNTHESIS What affects photosynthesis? Temperature: Temperature Low = Rate of photosynthesis low Temperature Increases = Rate of photosynthesis increases If temperature too hot, rate drops

Oxygen and Sugar! 27

Cellular Respiration ALL organisms break down simple sugars (C6H12O6) for the energy they contain

Cellular Respiration C6H12O6 + O2  CO2 + H2O + ENERGY Sugar is broken down into Carbon Dioxide (CO2) and Water (H2O) The Chemical Formula looks like this: C6H12O6 + O2  CO2 + H2O + ENERGY Sugar + Oxygen  Carbon Dioxide + water + ENERGY Or in English…….

What’s this energy for? To build new cell parts To repair cell parts To reproduce cells

Where does it happen? Cellular Respiration occurs in the mitochondria!!!