Part 1

• Carbohydrates

Energy Release

• When bonds are broken, __________ is released for use by the cell

energy

Sucrose: A disaccharideGlucose Fructose

Monosaccharides

ATP

Energy Storage

Glucose: A Monosaccharide Fructose: A Monosaccharide

• When bonds are made, energy (E) is stored

Sucrose: A dissaccharide

Carbohydrates

1. Carbohydrates are:– an important energy (E) source– Cellular structures

2. Carbon, Hydrogen and Oxygen in a ratio of 1:2:1

3. General Formula (CH2O)nCH2O

Water = hydrateCarbon hydrate

Types of Carbohydrates

Monosaccharides (simple sugars) – Contain 3-7 Carbons each

• Examples: Glucose, Galactose, FructoseGlucose

Types of Carbohydrates, cont…

Disaccharides (two sugars)• Examples: Sucrose, Maltose, Lactose

– Maltose = Glucose + Glucose– Lactose = Glucose + Galactose

Sucrose

Glucose Fructose

Types of Carbohydrates, cont…

Polysaccharides (many sugars)• Examples: Starch, Glycogen, CelluloseStarch Cellulose

Chloroplast Starch

Glycogen

Liver Cell

Plant Cells

Plant Cells

Cellulose

Check for Understanding…I’m a carbohydrate polymer made of 4 monomers. What are my monomers called?

Monosaccharides, of course!

Part 2Bond Energy and Energy Storing

CompoundsATP, NADPH, FADH2, NADH

How is energy released?

• When bonds are made by dehydration synthesis, energy is stored within the bonds of the compound.

Sucrose: A disaccharideGlucose Fructose

Monosaccharides

ATP

OH HO

How is energy released?

• When bonds are broken by hydrolysis, __________ is released from the bondsenergy

Sucrose: A disaccharideGlucose Fructose

Monosaccharides

ATP

What are some examples of common energy storing

compounds?

1. ATP (Most important usable energy for the cell.)

2. NADPH

3. FADH2

4. NADH

How is ATP made?

• ATP is made from the precursor AMP (Adenosine Mono-phosphate)

• If a phophate and energy is added to AMP, ADP is created.

• Furthermore, if another phosphate is added to ADP, ATP is created.

How ATP is Made

• AMP

• ADP

• ATP

A

A

A

P P

P P P

P

Equation for ATP synthesis

• ADP + P + energy ATP

How are NADPH, FADH2, and NADH made?

• NADP+ + H+ + electrons NADPH• FAD+ + 2H+ + electrons FADH2

• NAD+ + H+ + electrons NADH• Notice that high energy electrons and

hydrogen ions (H+) are needed to create NADPH, FADH2 and NADH.

Part 3Introduction to Photosynthesis

1. Mesophyll

1. Mesophyll

A layer of cells that contain & are responsible for most of the plant’s photosynthesis

chloroplasts

Page 2

2. Stomata

Openings in plant leaves that allow for to occur

(CO2) passes in and (O2) passes out.

CO2

O2

gas exchange

Carbon Dioxide Oxygen

Page 2

Mesophyll Cell

3. Chloroplast

The site of Photosynthesis

Double-membrane bound organelle

5. Inner membrane

4. Outer membrane

Page 2

6. Stroma7. Thylakoid

8. Grana

8. Grana

resides in these membranes

Chlorophyll

Page 2

Pathway of Photosynthesis

On your own, balance this equation:

CO2 + H2O + (Light) C6H12O6 + O2

Reactants must equal Products

16 66

Carbon

Hydrogen

Oxygen

Carbon

Hydrogen

Oxygen

6

12

6

12

18 18

Page 4

Thylakoid

Label the image in your notes, and fill in the notes provided

Page 4

Page 4

Page 4

Photosynthesis: The Light Reaction

• are chemical factories powered by the sun.

• Their thylakoids transform light energy into the energy of

and .

Page 5

Chloroplasts

NADPH ATP

Page 5

The Nature of Light

• The particles of light are called

.

Page 5

The Nature of Light

photons

Why are leaves green?Substances that absorb light are called

Page 5

Chlorophyll a

Chlorophyll b

Carotenoids

Chlorophyll absorbs and light, reflecting

pigments

red blue green

Fluorescence of ChlorophyllE

nerg

y of

ele

ctro

n

Photon

Chlorophyll molecule

e-

Heat

Fluorescence

Ground state

High energy state

Photosystems: Harvest LightPhoton

Transfer of Energy Antenna pigment molecules

Reaction Center Chlorophyll

Primary Electron AcceptorElectron Transfer (high energy state)

Light ReactionE

nerg

y of

Ele

ctro

ns

Primary Acceptor

2 e-

H2O

1) photons

2H+ + O2

2e-

Photosystem II Photosystem I

2) Spliiting of water releases O2

gas and refills 2e- to the chlorophill pigment

Electron Transport Chain (ETC)

3) Electrons “fall” in energy, moving through a protein complex called the ETC, and ATP is created from this energy

ATP

2e-

4) photons

Primary Acceptor 2e-

ETCNADP+ + H+

NADPH making enzyme

NADPH

5)

Mechanical analogy for the light reactions

1. Photon excites an electron in Photosystem II

2. ATP is produced during this stage (ETC)

3. The electron moves on to Photosystem I

4. An electron is excited by another photon

5. NADPH is produced

ATP Synthetase

• An enzyme embedded in the

Thylakoid membrane

thylakoid membrane

• Creates ATP from the electron’s energy in the ETC

ProteinComplex

Enzyme

Summary of the Light Reaction

+ ++ +

+ +

ATP

+++

+

++

++

+

+

+

++

+

+

+

+

+

+

++

2e-4e-

NADPH

Dark Reaction:An Overview

• The General Formula for Photosynthesis is:

6CO2 + 6H2O + (Light ) C6H12O6 +6O2

• Which of these reactants has not been accounted for so far?

ATP & NADPH energy are used to convert

CO2 into glucoseNADPH

ATP

CO2

Sugar!

This is done in a three-phase cycle…

STEP 1: Carbon fixation

5-Carbon Sugar (RuBP)

+ CO2

two 3-Carbon Compounds (PGA)

RuBP PGA

ATP and NADPH energy is used

This energy rearranges atoms of PGA

PGA changes into PGAL, a different 3-carbon sugar

PGAL

Phase 2: Makes PGAL, a 3-Carbon sugar

PGAL

Phase 2: Makes PGAL, a 3-Carbon sugar

Let’s play the photosynthesis magnet board race!