photosynthesis the process autotrophs use to make glucose sugars from carbon sources, water, and...

PhotosynthesisThe process autotrophs use to

make glucose sugars from carbon sources, water, and light energy

6CO2 + 6H2O C6H12O6 + 6O2

sunlight

Radiant energycarbohydrates

Respiration

How energy flows through the ecosystem

Photosynthesis

HeterotrophsHeterotrophs

Autotrophs

heat

How organisms get carbon energy

1. Autotrophs: able to produce own glucose – Ex: plants, algae, cyanobacteria– Also called: producers

2. Heterotrophs: must take in glucose from outside source

– Ex: animals, fungus, most bacteria, protozoans

– Also called: consumers

RespirationPhotosynthesis

Stored Chemical Energy(in the form of Glucose)

Light Energyfrom the sun

Energy for Cellin the form of ATP

Using oxygen; releasing w

ater & CO

2

Usi

ng w

ater

& C

O 2; re

leas

ing

oxyg

en

Why is a carbon source from sugars so important?• The carbons are needed to make ATP

molecules, which provide energy for metabolic reactions.

Adenine Ribose 3 Phosphate groups

ADP and ATP

• To get energy out of ATP, the bond between two phosphate groups is broken.

ADP ATP

Energy

EnergyAdenosine diphosphate (ADP) + Phosphate Adenosine triphosphate (ATP)

Partiallychargedbattery

Fullychargedbattery

Where and how are sugars made?Light Energy

Chloroplast

CO2 + H2O Sugars + O2

Photosynthesis video

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Pigments

• Chlorophyll is a pigment, a molecule that can absorb light energy.

• Unused light is reflected.

• What is the color of the wavelength least used by chlorophyll?

Absorption of Light byChlorophyll a and Chlorophyll b

V B G YO R

Chlorophyll b

Chlorophyll a

2. Photosynthesis pigments

• A. chlorophyll a(light green)

• B. chlorophyll b(dark green)

• C. xanthophyll(yellow)

• D. carotenoid– (orange)

Chromatography

• The process of separating colored solutions to determine the number of pigments in the solution

How does photosynthesis work?

1. Light dependent reaction

2. Calvin cycle

ChloroplastLight

Sugars

CO2

Light-Dependent Reactions

CalvinCycle

NADPH

ATP

ADP + PNADP+

Chloroplast

H20

O2

Step 1: Light dependent reaction

HydrogenIon Movement

Photosystem II

InnerThylakoidSpace

ThylakoidMembrane

Stroma

ATP synthase

Electron Transport Chain Photosystem I ATP Formation

Chloroplast

Light dependent reaction

• Pigments (chlorophyll) inside of the chloroplasts are arranged into photosystems (PSI and PSII).

• Photosystems absorb sunlight.

• Electrons become energized and help to produce NADPH.

3. Light Dependent

reactions• location:

grana of chloroplast• Photosystem II: energized chlorophyll releases

energy to split water into Oxygen (released) and Hydrogen (the H is carried by NADP to be used later in Calvin cycle)

• Photosystem I: energized chlorophyll releases energy to add phosphate to ADP to make ATP (to be used later in the Calvin cycle)

Light dependent video (1)

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Light dependent video (2)

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Step 2: Calvin cycle

ChloropIast

CO2 Enters the Cycle

Energy Input

5-CarbonMoleculesRegenerated

Sugars and other compounds

6-Carbon SugarProduced

4. Light independent reactions(Calvin cycle)

• Location: stroma (fluid) of chloroplast

• Carbons? CO2 is “fixed” by RuBP & begins the cycle becoming PGA, then PGAL after hydrogen (from NADP) and energy (from ATP) are added

• Products? RuBP is recycled for next time & Glucose (sugar/food) is made (from 6 turns of cycle)

Calvin cycle

• The NADPH supplies the energy needed to change the CO2 taken into the cell into a 6 carbon molecule.

• This 6 carbon molecule is made into sugars.

glucose

Sunlight

Light-dependentReactions

water

oxygen

Calvin Cycle

Carbon Dioxide Glucose

NADPH2

ATP

Within chloroplasts

RuBP

PGA

PGAL

Calvin cycle video

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