PHOTOSYNTHESIS NOTESObjective: We will learn that all living things get their energy from the sun. We will learn the steps of photosynthesis and what reactants are used to make energy products.

Vocabulary:

ATP

ADP

Autotroph

Heterotroph

Chlorophyll

Anthocyanin

Carotinoid

Chloroplast

Van Helmont

Joseph Priestley

Jan Ingenhousz

Melvin Calvin

Sam Ruben & Martin Kamen

Richard Willstatter

Julius Mayer

C3

C4

CAM

Glucose

Granum

Photosynthesis

Light Reactions

Dark Reactions

Stomata

Stroma

Thylakoid

ATP Synthase

Calvin Cycle

Dark Reactions

Rubisco

Electron Transport Chain

Photosystem I

Photosystem II

Living things need energy

Autotrophs: plants and some _________________________ are able to use the energy from the sun to produce food.

Heterotrophs: animals, some prokaryotes, and most _______________________________ organisms cannot use the sun’s energy directly, therefore they need to consume __________________________________ as a food source.

ATP: Adensosine Tri-phosphate

ATP is the biochemical molecule plants & animals use as ________________: A phosphate can be released to get energy!

ADP (adenosine di-phosphate) has only _____ phosphates, it results after the use of a phosphate for energy.

ATP and ADP can be thought of like a battery: ATP is like a full battery, and ADP is like a low battery.

When do cells use energy?

Active Transport: Moving ions across cell membrane through a protein pump. Ex: Sodium-Potassium Pump in your muscles.

Synthesis of Nucleic Acids: Making DNA & RNA. Ex: Mitosis and Protein Synthesis. Movement: work and exercise. ATP needed for cell movement (cilia and flagella) and division during

Mitosis.

ATP is actually only good for ______________ term use, its poor at long-term storage of large amounts of energy. Glucose is much better at _______________-term storage of energy. Glucose stores 90x more energy than ATP.

Cells keep a small supply of ATP; they generate more from ADP when needed, by breaking down carbs like glucose.

Think-Pair-Share!

What does ATP stand for? What is it?

How is energy released? What is the resulting molecule?

When would a cell need to use ATP?

Scientists of Photosynthesis & Plants!

Van Helmont

Joseph Priestley

Jan Ingenhousz

Melvin Calvin

Sam Ruben & Martin Kamen

Richard Willstatter

Julius Mayer

Photosynthesis definition: The process of converting light energy into ________________________________________ energy.

Structure of a Leaf:

Reactants and Products of Photosynthesis:

Reactants: CO2 + H2O (carbon dioxide + water) *Light energy for activation Products: C6H12O6 + O2 (glucose + oxygen)

CHO always make _______________________________________ in a 1:2:1 ratio 😊

Think-Pair-Share!

What is photosynthesis a process of?

What is the formula for photosynthesis?

What type of cell in a leaf performs Photosynthesis?

Types of Plants

Different type of plants perform photosynthesis in different parts

of their leaves, or at different times of day.

C3: Normal/Everyday plants: all of Photosynthesis occurs in the _____________________________ cells. C4: Tropical plants (hot and wet environment): Light reactions occur in the mesophyll cells, and Dark

reactions occur in the _________________________________________________ cells. CAM: Dry area plants (cactus): only open their stomata at night to let in CO2 to reduce ________________________

on hot days. They perform Light reactions at _________________, and Dark reactions during the day.

Where does Photosynthesis occur?

Chloroplast: Organelle in plant cells only = site of photosynthesis.

Chlorophyll: ________________________ that absorbs light. Appears green because it absorbs blue and red light. Chlorophyll is just one pigment in plants, there are other colors/pigments too:

o Anthocyanin makes plants red.o Carotenoids make plants look yellow or orange

It takes a lot of sunlight to make green chlorophyll, when the days get ____________________ in the fall chlorophyll production stops and we only see the anthocyanins and carotenoids!

Bell Ringer Questions:

Differentiate between ADP & ATP.

Draw a picture and label where energy is released from.

Draw the organelle that photosynthesis occurs in:

Label the structures and describe the different pigments it can contain.

Write the complete chemical formula for photosynthesis.

Objective: We will learn the details of the light and dark reactions of photosynthesis, and distinguish between the reactants and products of these processes.

Photosynthesis Reactions

Photosynthesis is performed through ____ sets of reactions: the Light Reactions, and the Dark Reactions. Both are necessary, and must occur in the correct order: Light then dark.

Light Reactions

Location: Thylakoid Membrane inside the Chloroplast of plant cells.

Also called: Photophosphorylation

Requires ______________________.

Dark Reactions

Location: Stroma fluid inside the Chloroplast of plant cells.

Also called: Calvin Cycle

Does ________ require light.

Light Reactions

Step 1: “______________________________________” Sunlight as absorbed by the green chlorophyll pigment in the thylakoid membrane. Sunlight photons (energy) is converted into ______________________ by bouncing around the thylakoids in the granum stacks to gain power. The high-powered electrons are then used to break water molecules in a process called ______________________________: water is broken into H+ ions and O2 gas. The thylakoid membrane fills up with lots of H+ ions.

Step 2: “Photosystem I” The electrons from the sun are used to ____________ H+ with a molecule called NADP+ to make NADPH (it carries energy like ATP).

Step 3: “ATP Creation” Highly concentrated H+ ions move from the thylakoid membrane through a protein channel called “____________________________________________” where the H+ provides energy for ADP to bond with a phosphorous molecule to create ATP (in the stroma fluid). The movement of H+ ions from high to low is called Chemiosmosis.

Reactants for Light Reactions:

Sunlight, water, NADP+, and ADP

Products of the Light Reactions:

O2 gas, NADPH, and ATP

Remember: photosynthesis occurs inside the chloroplasts that are found in the _________________ cells of plant leaves.

Think-Pair-Share!

Where do electrons come from?

What are they called?

What happens during and after hydrolysis?

How is ATP made?

Dark Reactions (Calvin Cycle)

Step 1: “Carbon Fixation” CO2 molecule combines with a 5-carbon molecule called _________________, which produces an unstable 6-carbon molecule that instantly ____________________ in half to make two 3-carbon molecules called _______________. This reaction is performed by an enzyme called rubisco.

Step 2: “Reduction” ATP and NADPH (from the light reactions) are used as an __________________ source to convert 3PGA into a 3-carbon sugar called _________.

Step 3: “Regeneration” G3P molecules are used to make glucose (C6H12O6) the others are ___________________ and converted, using ATP, into the 5-carbon RuBP to be used again at the start of the cycle.

Reactants for Calvin Cycle:

NADPH, ATP, CO2

Products of the Calvin Cycle:

NADP+, ADP

Think-Pair-Share!

What is another name for Dark Reactions?

Where does it take place?

What is the main product?

Photosynthesis Reactions

Light Reactions:

H20 + electron = O2 and H+

NADP+ + H+ = NADPH

ADP + P = ATP

Dark Reactions:

ATP + NADPH + CO2 = C6H12O6

Photosynthesis Formula

6CO2 + 6H2O C6H12O6 + 6O2

Reactants: 6 carbon dioxides + 6 water molecules

Products: 1 glucose + 6 oxygen molecules

Bell Ringer Questions

Outline the 3 steps of the Light Reactions

1.

2.

3.

Outline the 3 steps of the Dark Reactions

1.

2.

3.

Write out the complete chemical reaction formula for Photosynthesis

Factors that affect Photosynthesis

If a ________________________ is given to a plant in a low/high dose, it can either speed up or slow down the photosynthesis reactions.

Light Intensity: low light reduced rate

high light elevated rate

CO2 Levels: low CO2 reduced photosynthesis

high CO2 more photosynthesis

Temperature: cold temps reduced rates

hot temps increased rates

However, the rate at which photosynthesis occurs is __________ unlimited. There is a point where plants need dark, less CO2, lower temperatures to optimally function year-round.

Types of Plants

Recall that there are 3 main types of photosynthesis: C3, C4, and CAM. Each require _______________________ conditions to perform Photosynthesis __________________________.