Can plants think? Do plants have a social life?. PHOTOSYNTHESIS: The starting point of life*

Can plants think?

Do plants have a social life?

PHOTOSYNTHESIS:

The starting point of life*

1st concept to know:Living things run on

batteries.

What is the battery?

1st concept to know:Living things run on

batteries.

What is the battery?

We recharge ATP from sugar (glucose)…where does sugar come from?

Adenosine Triphosphate (ATP) Molecule that provides life’s energy.

– Works by popping of a phosphate group, releasing stored energy

– 3 parts:

Adenine Ribose 3 Phosphate groups

ADP ATP

Energy

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

Partiallychargedbattery

Fullychargedbattery

Section 8-1

Figure 8-3 Comparison of ADP and ATP to a Battery

An organism can either make its own food, or eat it. They are called autotrophs or heterotrophs

Nutrition

Nutrition

AutotrophicNutrition

HeterotrophicNutrition

ChemosynthesisPhotosynthesis

Green Plants

Ingestion,Digestion,Egestion

PHOTOSYNTHESIS:

process which light energy is converted into

sugar energy

PBS interactive

Major Players in the Development of the Photosynthesis Equation…how did they each contribute? What where their results? Conclusions?

• Van Helmont: what ingredient makes up plants?

• Priestly: What are plant byproducts?

• Ingenhousz: Is light really that important?

Conclusion of scientists:

Leaf Cross section

Plants: Leaf Cross Section

Stomates and Guard cells

Plants review:

• Vascular Tissue:– Xylem, transports water– Phloem, transports food

• Gas intake:– Guard cells open forming STOMATES– Lenticels in bark

Absorption of Light byChlorophyll a and Chlorophyll b

V B G YO R

Chlorophyll b

Chlorophyll a

Section 8-2

Figure 8-5 Chlorophyll Light Absorption

http://seawifs.gsfc.nasa.gov/SEAWIFS.html

Chlorophyll, a green pigment, allows plants to absorb light energy. Energy absorption, however, must be consistent with allowable (basal to excited state) electron transitions within the chlorophyll molecule (click 1). Because these transitions are not continuous, a plant obtains energy only at certain frequencies of light. Energy insufficient to reach an excited state is not absorbed (click 1). Similarly, energy that drives an electron past one energy level but is insufficient to reach a second is not absorbed (click 1). To be absorbed, the energy must be sufficient to reach only allowable energy states (click 1). This simple rule of quantum physics is all you need to know to understand an absorption spectra of chlorophyll (click 1).

300 700600500400

Chlorophyll bAbsorptionIntensity Chlorophyll a

excited states

ground state

1

2

Chloroplast AnatomyChloroplast Anatomy

Chloroplast

water

O2

Sugars

CO2

Light-Dependent Reactions

CalvinCycle

NADPH

ATP

ADP + PNADP+Chloroplast

Section 8-3

Figure 8-7 Photosynthesis: An Overview

PhotosynthesisPhotosynthesis

HH22OO COCO22

OO22 CC66HH1212OO66

Light Light ReactionReaction

Dark ReactionDark Reaction

Light is AdsorbedLight is AdsorbedBy By

ChlorophyllChlorophyll

Which splitsWhich splitswaterwater

ChloroplastChloroplast

ATP andATP andNADPHNADPH22

ADPADPNADPNADP

Calvin CycleCalvin Cycle

EnergyEnergy

Used Energy and is Used Energy and is recycled.recycled.

++

++

HydrogenIon Movement

Photosystem II

InnerThylakoidSpace

ThylakoidMembrane

Stroma

ATP synthase

Electron Transport Chain Photosystem I ATP Formation

Chloroplast

Resources:

Photosynthesis animation, VCAC

Photosynthesis video, Mastering Biology

Light-Dependent Reactions

ChloropIast

CO2 Enters the Cycle

Energy Input

5-CarbonMoleculesRegenerated

Sugars and other compounds

6-Carbon SugarProduced

Section 8-3

Figure 8-11 Calvin Cycle

Comparison of Mitochondria

and Chloroplasts

Comparison of Mitochondria

and Chloroplasts

Both have a large amount of internal membrane surface area.

Both have their own ribosomes.

Both have their own genomes.

Both produce a large amount of ATP.

Both derive energy for ATP synthesis from H+ pumps.

Both have a large amount of internal membrane surface area.

Both have their own ribosomes.

Both have their own genomes.

Both produce a large amount of ATP.

Both derive energy for ATP synthesis from H+ pumps.

The mitochondrial genome (in humans) is about 16,000nucleotides long.

The chloroplast genome is about 10x the size of the mitochondrial genome.

The mitochondrial genome (in humans) is about 16,000nucleotides long.

The chloroplast genome is about 10x the size of the mitochondrial genome.

Quick Quiz

1.What is the ultimate purpose of photosynthesis?

2.Where does the Calvin Cycle occur?

3.What is the purpose of water?

4.What is the purpose of light?

5.What is the primary raw ingredient of sugar?

6.Where do the Light-Dependent Reactions occur?

7.What makes the turbine spin that makes ATP?

8.What is the waste product of the Light-Dependent Reactions?

9.Why are plants green?

includes

of

take place intakes place in uses

to produce to produce

use

Section 8-3

Test yourself

Photosynthesis

includes

of

take place intakes place in uses

to produce to produce

use

Light-dependentreactions

thylakoidsenergy fromsunlight

ATP NADPH O2 Chloroplasts

Section 8-3

Do Now

Calvin cycle

ATP NADPH

High-energysugars

stroma