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 __________________________.