Happy Thursday!

• Please take out a pencil and place all of your belongings on the end counter except for your book.

• Please don’t mess with any of the lab supplies yet

Photosynthesis

Chapter 8

Announcements

• Exams– Review tomorrow

• Collect Extra Credit• Say Hi to Mr. Jahn

Agenda

• Mini-Lecture/ Discussion• Leaf Activity• Class Discussion – Debrief Activity

Standards & Objective

• CSBS – 1F• Students know usable energy is captured from sunlight by

chloroplasts and is stored through the synthesis of sugar from carbon dioxide.

• Today’s Goal• Recognize differences in leaf structures and interpret how

these differences allow plants to diversify and perform photosynthesis at the optimum level in many different ecosystems.

The Leaf - Pg. 208 in your Text

Where does Photosynthesis take place?

• Where does photosynthesis take place?– In the Chloroplasts (in plant cells)

• Where are the Chloroplasts located?– In the green part (Leaves) of the plant

• Are all leaves exactly the same on different plants?

Leaf MorphologyLeaf Morphology

Where does Photosynthesis take place?

• Where does photosynthesis take place?– In the Chloroplasts

• Where are the Chloroplasts located?– In the green part (Leaves) of the plant

• Are all leaves exactly the same on different plants?• NO!

• But, Why?

Leaf Lab/Activity• Answer the pre-activity questions• Look at 4 types of leaves.

– Answer all the questions about the leaves– Hypothesis where leaf might be native, how does the

structure assist in the function?– Draw the Leaf so the whole specimen fits in the box– Using the DISSECTING MICROSCOPE, look at the leaf.

• Include magnification• Switch Stations every 7 minutes• Stop after 2 stations for discussion

Where does Photosynthesis take place?

• Where does photosynthesis take place?– In the Chloroplasts

• Where are the Chloroplasts located?– In the green part (Leaves) of the plant

• Are all leaves exactly the same on different plants?• NO!

• But, Why?

Activity Conclusion• What did you notice about leaf texture?• What did you notice about lead thickness?• How did the direction of veins differ?• Did any of these leaves seem like they were not

from the same ecosystem as the others?• How does the structure of the leaf affect water flow

around the plant?• How do all of these components combine to allow

plants to perform photosynthesis at an optimal level?

Homework

• Finish lab– All questions are answered– All pictures are drawn and detailed– Make sure everything is quality

IQ # 1 – 8.2• Yes, its 8.2, we’re going out of order 1. Write a one sentence summary for each of the following

scientists experiments: (p. 204-206)– Van Helmont– Preistly– Ingenhousz

2. Write out the photosynthesis reaction. Count and list the total number of carbon, hydrogen, and oxygen molecules on both sides of the reaction. Do they equal? (p. 206)

3. What four items does photosynthesis require? Define pigment and chlorophyll. Why are plants green?

Welcome Back!

• Today – – Grades will be updated at the end of the period

• Wednesday – – Extra Credit – 8.1-8.2 (or 8.3)

• Friday – – Quiz!

California State Standards

• Cell Biology1f: usable energy is captured from sunlight by chloroplasts and is stored through the synthesis of sugar from carbon dioxide

Today

• 8.2– IQ # 1– Lecture and Discussion– Tomorrow - Lab

A. Investigating Photosynthesis Investigations into photosynthesis began with the following question:

“When a tiny seedling grows into a tall tree with a mass of several tons, where does the tree’s increase in mass come from?”

1. ______________ Experiment (1643)

Put soil in pot and took mass

Took a seedling and took mass

Put seed in soil...watered...waited five years... the seedling became a tree.

He concluded that He determined the

                                      

    

Van Helmont’s

the mass came from water

the “hydrate” in the carbohydrate portion of photosynthesis

2. ___________ Experiment (1771)

Put a lit candle in a bell jar- Placed a mint plant in the jar with the candle-

Concluded

He determined

                                        

                    

Priestly’s

The flame died out.

Flame lasted longer

plants release a substance neededfor candle burning.

plants release oxygen

3. ________________Experiment (1779)

Put aquatic plants in light...

Put aquatic plants in dark... He determined:

4. _______________ (1948)

He determines

Known as the

Jan Ingenhousz

produced oxygen

No oxygen

Light is needed to produce oxygen

Melvin Calvin

carbon’s path to make glucose

Calvin’s cycle

8-2 Photosynthesis: An Overview

Photosynthesis=

Plants convert ______________ → ______________ through a series of oxidation/reduction reactions.

Process where plants use energy of sunlight to convert water and carbon dioxide into high-energy Carbohydrate (glucose)and oxygen, a waste product.

Sunlight energy Chemical energy

6 CO2 + 6H2O + SUNLIGHT → C6H12O6 (SUGAR) + 6O2

Reduction = Gain Electrons

Oxidation= Lose Electrons OIL RIG

6 CO2 + 6H2O + SUNLIGHT → C6H12O6 (SUGAR) + 6O2

sunlight

O2

CO2

H2O

C6H12O6

Light Energy

Chloroplast

CO2 + H2O Sugars + O2

Photosynthesis: Reactants and Products

B. Light and Pigments Photosynthesis requires ______ (soil), ____________ (air), and ____ (sun), and ___________ (a molecule in chloroplasts).

Energy from the sun is in the form of _____.

Sunlight= perceived as white light=

The wavelengths you can see are part of the _______________.

Plants capture light with light absorbing molecules called ________.

The main pigment is chlorophyll (2 kinds)1. 2.

water Carbon dioxidelight chlorophyll

light

A mixture of different wavelengths

Visible Spectrum

pigments

Chlorophyll aChlorophyll b

Absorption of Light byChlorophyll a and Chlorophyll b

V B G Y O R

Chlorophyll b

Chlorophyll a

Figure 8-5 Chlorophyll Light Absorption

Chlorophyll absorbs light in the __________ and ___ wavelengths

Gammarays

X-rays UV Infrared Micro-waves

Radiowaves

Visible light

Wavelength (nm)

Blue-violetred

Chlorophyll reflects ______ wavelengths (that’s why plants appear green)

The energy absorbed by chlorophyll is transferred to _________ (in chloroplasts) which makes photosynthesis work.

green

electrons

IQ # 1 – 8.2• Yes, its 8.2, we’re going out of order 1. Write a one sentence summary for each of the following

scientists experiments: (p. 204-206)– Van Helmont– Preistly– Ingenhousz

2. Write out the photosynthesis reaction. Count and list the total number of carbon, hydrogen, and oxygen molecules on both sides of the reaction. Do they equal? (p. 206)

3. What four items does photosynthesis require? Define pigment and chlorophyll. Why are plants green?

Chromatography Lab• Cut Chromatography paper strip in half (longways)• Black Ink Marker

– Draw line with marker ½ inch from bottom– Allow marker to dry. Put in Water/Solvent A.

• Make sure not to allow marker line to touch water directly

– Fold over top so the chromatography paper doesn’t fall into flask.

• Leaf Pigment– Using the spinach extract and the capillary tube, draw a line of

spinach ½ inch from the bottom– Repeat 20 times, allowing the extract to dry between each

application. – Place in acetone, fold over top, replace cap

• Make sure not to allow spinach line to touch acetone directly

Homework

• Finish Lab Questions• 8.1 and 8.2 Vocabulary Flashcards

IQ # 2 (8.1)1. How does the impala get its energy, how does the leopard

get its energy? How do they differ? What it the ultimate source of energy? (Fig. 8.1)

2. What is ATP? How is ATP released from ATP? What does it stand for? What is its function? How do ATP and ADP differ? Which is the storage form? (p. 202)

3. What is a common use for ATP? Which direction are each of the ions being pumped?

Wednesday Announcements

• TODAY IS A MAKE-UP DAY!!• Wednesday Afternoon

– Tutoring (pass back forms)– 8.1 & 8.2 (8.3)

• Thursday– Observation

• Friday– Lunch – Make-Up Lab– QUIZ (8.1 and 8.2)

Agenda

• IQ # 2• Review Lab• Lecture/ Discussion

– Section 8.1 – Energy and Life

8-1 Energy of Life

Energy=

Living organisms depend on energy.

Living things get energy from _______.

The ultimate source of energy is the _____.

The ability to do work

food

sun

A. Autotrophs and Heterotrophs

Autotrophs=

o Example: plants use sunlight to make food

Heterotrophs=

o Example: ___________- eat plants ___________- eat animals that have stored energy from plants they eat

___________- eat decomposing organisms

Organisms that make their own food

Organisms that need to consume food for energy

herbivores

carnivores

detritovores

Adenine Ribose 3 Phosphate groups

B. Chemical Energy and ATP•Forms of energy: light, heat, electricity, and

•_____ (Adenosine Triphosphate)=

Chemical energy (stored in bonds)

ATP

The basic energy source (chemical energy) of all cells

1. Storing Energy• ADP (Adenosine Diphospate) contains ____ phosphates

instead of 3.

• If a cell has extra energy,

2. Releasing Energy

• To release energy stored in ATP,

2

Small amounts can be stored by adding a phosphate group to ADP molecules to produce ATP.

The cell can break the high energy bond betweenthe 2nd and 3rd phosphate group

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

C. Using Biochemical Energy

How ATP is used in the cell- - aids in - -

Cells contain a small amount of ATP. Only enough to provide a few seconds of activity.

ATP is great at ________________ but not good at

C. Glucose stores ___ times more energy than ATP.

The energy stored in Glucose can be used to

Carry out active transportmoving organelles throughout the cell

Protein synthesisProducing light (ex. fireflys)

transferring energy Storing large amounts of energy

90

regenerate ATP when the cell needs it.

Homework

• Study for 10 minutes using flashcards• Bring Coloring Items

– Colored Pencils– Markers– Crayons

• Section Assessment 8.1 – Pg. 203 #1-5

Light

Chloroplast

Reflectedlight

Absorbedlight

Transmittedlight

8-3 The Reactions of Photosynthesis A. Inside a Chloroplast

•Site of Photosynthesis=

The chloroplasts

B. Electron Carriers Sunlight energy is transferred to

The electrons

High energy electrons require ANALOGY: If you wanted to transfer hot coals from one campfire to another, it requires a special carrier like a pan or bucket.

Electron carriers pass electrons from carrier to carrier to carrier;

A Key electron carrier in photosynthesis is NADP+. NADP+ + + →→ (electron carrier) (high energy electrons) (hydrogen ions) (energy storing compound)

When energy is needed to do cellular work, the

electrons in chlorophyll.

gain a lot of energy.

a special carrier (molecule/compound).

Forming an electron transport chain.

2e- H+ NADPH

Covalent bonds of NADPH are broken to releasethe high energy electrons.

Photosynthesis is a two part process:1.

-aka: 2.

-aka: -aka: -aka:

Light

O2Sugars

CO2

Light-Dependent Reactions

CalvinCycle

NADPHATP

ADP + PNADP+Chloroplast

Section 8-3Figure 8-7 Photosynthesis: An Overview

Light-dependent reactions (located in thylakoid membranes)Light Reaction

Light-independent reactions (located in stroma)Dark reactionCalvin CycleCarbon fixation

H20

Chloroplast

• An overview of photosynthesis

Figure 7.5

Light

Chloroplast

LIGHTREACTIONS(in grana)

CALVINCYCLE

(in stroma)

Electrons

H2O

O2

CO2

NADP+

ADP+ P

Sugar

ATP

NADPH

C. Light-Dependent Reactions (Requires Light)· Located in the ___________________________

· In the light reaction, ___________ is used to produce

_____ and _______

thylakoid membrane

light energyATP NADPH

KEY PLAYERS IN LIGHT REACTION:

    Photosystem I and II:

    Electron carriers:

    Water:

• ATP Synthase:

Clusters of chlorophyll pigment

ADP and NADP+

Donates electrons

Enzyme (protein) that makes ATP

Primaryelectron acceptor

Primaryelectron acceptor

Electron transport chain

Electron transport

Photons

PHOTOSYSTEM I

PHOTOSYSTEM II

Energy forsynthesis of

by chemiosmosis

• The production of ATP by chemiosmosis in photosynthesis

Figure 7.9

Thylakoidcompartment(high H+)

Thylakoidmembrane

Stroma(low H+)

Light

Antennamolecules

Light

ELECTRON TRANSPORT CHAIN

PHOTOSYSTEM II PHOTOSYSTEM I ATP SYNTHASE

A. Photosystem II (PSII) * Absorbs light to

2H2O

o e- =

o O2 =

o H+=

B. Electron Transport Chain * The light energy

* The electrons get passed

split (break up) water molecules

→ 4H+ + 4e- + O2

Donated to chlorophyll

Released into air providing oxygen for us

Released inside the thylakoid membrane

excites electrons increasing their energy level.

down an electron transport chain tophotosystem I (PSI)

C. Photosystem I· Light energy energizes electrons.· NADP+ accepts the electrons and an H+ and are

used to make _________. D. Hydrogen Ion Movement

· When water splits,

· The difference in charges

E. ATP Formation

· _____ do not cross the membrane directly. It needs the help of a membrane protein.

· H+ ions pass through the protein:

NADPH

H+ ions fill up the inner thylakoid membrane (making it positively charged). As a result, the stroma is negatively charged.

Provides the energy to make ATP.

Ions

ATP synthase is an enzyme that converts ADP to ATP

PRODUCTS OF THE LIGHT REACTION:

· ____ : Released in the air

· ______________: These contain abundant chemical energy but they are unstable. So, they are used to power the dark reaction to _________________ which can store the energy for longer periods of time.

O2

ATP & NADPH

help build glucose

ChloropIast

CO2 Enters the Cycle

Energy Input

5-CarbonMoleculesRegenerated

Sugars and other compounds

6-Carbon SugarProduced

D. The Calvin Cycle (dark reaction; light independent) * Occurs in the

Figure 8-11 Calvin Cycle

Stroma with or without light.

DARK REACTION PROCESS: A. CO2 enters the system• • product=

B. Energy input• The _________________________________ are used to

C. 6-Carbon Sugar is produced• ___ of the 12 3-C are used to make glucose and other compounds.

D. 5-Carbon Molecules Regenerated• ___ remaining 3-C are converted into 6 5-C molecules

6 CO2 combines with 6 5-C compounds12 3-C compounds

ATP & NADPH (from the light reaction)convert the 12 3-C compounds into a higher energy form.

2

10

PRODUCTS OF THE CALVIN CYCLE (DARK REACTION):*

E. Factors Affecting Photosynthesis* * Plants often have a ______ coating to protect against

* * The greater the _____________, the better photosynthesis functions (up to a point).

High Energy Sugars

Shortage of water can stop/slow down photosynthesis

waxy

Very low/high temperatures (damages enzymes) can stop/slow down photosynthesis (optimal temp.= 0°– 35° C

Light intensity

Photosynthesis

includes

of

take place intakes place in uses

to produce to produce

use

Light-dependentreactions

Calvin cycle

Thylakoidmembranes Stroma NADPHATPEnergy from

sunlight

ATP NADPH O2 Chloroplasts High-energysugars

Section 8-3

Concept Map

Section 23-4

Veins

Xylem

PhloemVein

Cuticle

Epidermis

Palisademesophyll

Epidermis

Stoma

Guardcells

Spongymesophyll

Figure 23–18 The Internal Structure of a Leaf

Stomata Opening and ClosingStomata Opening and Closing