Photosynthesis and Cellular Respiration NOTES
NAME_____________________
Chemical Reactions
A chemical reaction is the process of rearranging ___________ to create new compounds by breaking and forming
chemical _________. During chemical reactions __________ is either stored or released.
A chemical equation uses symbols to show what occurs during a ________________. It can be thought of as the
“recipe” for a compound.
Example:
2H2 + O2
2H2O
Reactants – substances used in the reaction; located on the left side of the equation.
Products – substances produced in the reaction; located on the right side of the equation.
What are the reactants in this equation?
What are the products in this reaction?
If we wanted to make 4 molecules of H2O, how many O2 would we need?__________
If we used 8 molecules of O2, how many molecules of H2O would we make?_______
Fe + CuCl2
FeCl2 + Cu
What are the products in this equation?
What are the reactants in this equation?
Chemical reactions must obey the _________________________________. The Law of Conservation of Mass states
that mass cannot be created or destroyed.
What does this mean for chemical reactions?
All chemical equations must obey the law of conservation of mass. When an equation obeys the law of conservation of
mass we say the equation is BALANCED (these represent reactions that can happen). When an equation does NOT obey
the law of conservation of mass we say it is UNBALANCED (an unbalanced equation represents something that will never
happen).
Examples: 2H2 + O2
2H2O
How many atoms of hydrogen are in the reactants? Product?
How many atoms of oxygen are in the reactants? Products?
Is this equation balanced? ___________ Why or why not?
Examples: H2 + O2
H2O
Energy in Living Things
What is Energy?
1
What do living things use energy for?
Cells get most of their energy from _______. Cells must be able to _______ this energy. Why?
Law of Conservation of Energy -
Four forms of energy Important to Life
1. Macromolecules – energy is stored in the _________ ________ of macromolecules.
Carbohydrates (Sugars)
Lipids (Fats)
Proteins
Carbohydrates (Sugars)–
Lipids (Fats) –
Proteins –
Four forms of energy Important to Life
2. Light – a ________ that has energy in the form of _________; this form is energy is used by __________ during
_________________.
3. ATP – Adenosine Triphosphate – the primary source of energy used by cells.
When the last phosphate is removed, ___________ is released.
Where does the energy in ATP come from?
Energy from __________ is stored in chemical bonds in ATP.
4. Electrons – Electrons (and their energy can be moved from one _________ to another.
Electron Carriers – special compounds that easily gain and lose electrons and can transfer energy from one place to
another.
Examples:
Enzymes
Enzymes 2
Why are enzymes needed?
How do enzymes work?
Enzymes lower the activation energy of a chemical reaction. Activation Energy is the energy needed to ______ a
chemical reaction.
DRAW THE CHART
Each enzyme has a specific ________ based on how the ________ is folded.
Substrate –
Each enzyme binds only to certain substrates. In order for the substrate to bind to the enzyme it must be the right
________.
The place where the substrate binds to the enzyme is called the _______ ______
Once the enzyme and substrate bind, a reaction occurs.
Draw a picture explaining how an enzyme works in the space below.
Example: The reaction shown below helps convert CO2 into a form that is more easily carried through the bloodstream.
Without enzymes this reaction wouldn’t happen fast enough and dangerous levels of CO2 would build up in the
bloodstream. The enzyme carbonic anhydrase allows this reaction to happen 10 million times faster.
Controlling Enzymes
Enzymes don’t always need to be “ON.” There are 2 ways to turn an enzyme “OFF.”
Competitive Inhibition –
Non- Competitive Inhibition –
Overview of Photosynthesis
3
Photosynthesis – the process in which plants use energy of ________ to convert ______ and ______ _______ into highenergy ________ and _________ a waste product.
Equation:
6CO2 +12H2O
C6H12O6 + 602 + 6H2O
A side note: structure of carbohydrates – carbohydrates are molecules made of _______, _________, and ________.
Location: Photosynthesis takes place in the ___________ of plants cell
Grana –
Stroma –
Thylakoid –
Chlorophyll –
Pigment- light absorbing molecules
Details of Photosynthesis
Equation:
6CO2 +12H2O
C6H12O6 + 602 + 6H2O
Purpose:
Remember: Photosynthesis has 2 main stages
Light Dependent Reactions use _________ and ________. Energy is temporarily stored in _______ and _________.
________ is given off as a waste product.
Light Independent Reactions (Calvin Cycle) uses _______ to convert the energy from _______ and _________ into
________. ________is given off as a waste product.
Photosynthesis (light dependent)
Location:
Materials Needed:
Final Products:
Stage 1: Light Dependent Reactions: Capturing The sun’s energy
1. Energy from light strikes a _______________ molecule in the membrane of the thylakoid. This light energy
excites an _________________ and it passes through a chain of molecule called the
_______________________. As it moves it ____________ energy.
2. Water in the plant is broken into, __________ __________ and __________________.
4
3. The ____________ replace the one lost from chlorophyll The O combine to form O2 and leave as a waste
product.
4. The movement of electrons causes more H+ to move into the _________________
5. Light strikes a 2nd chlorophyll molecule and the ________________ is reenergized . This high-energy electron is picked
up by ______________ (an electron carrier) to form NADPH.
6. As this happens over and over again protons (H+) build up in the thylakoid. They can only get across the membrane
by going through a ______________ The energy from the H+ moving through the channel converts ADP to __________.
Stage 2: The Calvin Cycle – Making Glucose
Location:
Materials needed:
Final products:
Main Idea: Energy stored in ____ and _____ from the light reaction is used in the Calvin cycle to convert ________
________ into high-energy sugars (Glucose).
Intro to Respiration
The process by which _______________ are burned in the cell in order to produce __________.
Purpose: to store ________ from food in _____ so cells can carry out life processes Remember: for cells to function they
need energy; the main form of energy used by cells is ____.
The equation :
Glucose – Made by plants in photosynthesis; has LOTS of ______, but it is not in a usable form.
Oxygen – produced by _______ during photosynthesis
ATP – the main source of ________ used by all Living things
Water – released into the air as waste
Location:
Comparing Photosynthesis and Cellular Respiration------------------ DRAW THE CHART
As ________ is used up it must be replaced. The energy to build more ________ comes from __________. It takes
some energy to break down food molecules, BUT cells get ____________ from the food that they use to break it down.
What is the major source of energy for organisms? Where does it come from?
Details of Respiration
Respiration
5
Equation:
Purpose:
Summary of Energy Flow: Energy from __________ is transferred to electron carriers and then to _________.
Glucose – one of the most basic carbohydrates; starting material for respiration
ATP –
NAD+/NADPH+H - an electron carrier
FAD/FADH2 – another electron carrier
The first step of all forms of respiration is ___________________. After that if no oxygen is present the cell goes through
fermentation. If oxygen is present the cell proceeds to cellular respiration.
The steps of cellular respiration are: The Krebs Cycle and Electron Transport----------------sketch the picture
Step 1: Glycolysis: Getting things Started
Location:
Materials Needed:
Final Products:
Main Idea: Glucose is broken down into smaller sugars. ____ ATP are used and ____ ATP are produced for a net gain of
____ ATP. Some energy is Stored in _________.
Step 2: The Krebs Cycle: Storing energy in electron Carriers
Location:
Materials Needed:
Final Products:
Main Idea: The smaller sugars are broken down even further. The carbon atoms from the sugars combine with O2 to
form______ which is given off as a waste product. The energy from the sugars is stored in _________ and _________.
Step 3: Electron Transport: Getting Usable Energy
Location:
6
Materials Needed:
Final Products:
Main Idea: Energy that has stored in _________ and ________ is converted to _______ as electrons are passed along
the electron transport chain. At the end of the chain electrons combine with H+ and Oxygen to form ___________
Totals:
______ ATP can be produced from one molecule of glucose. Six molecules of _____ and 6 molecules of _____ are given
off as waste products.
Fermentation
2 Types of Respiration:
1. With _____________ - Aerobic Respiration. When respiration happens in the presence of oxygen a
___________________ of ATP is produced.
2. Without ____________- Anaerobic Respiration. When respiration happens with NO oxygen, a _____________
of ATP is produced.
The first step of both of these processes is the same
Step 1: Glycolysis – first used by _______ ________ to make ATP, it is now used by ALL living things. Glycolysis breaks
down ___________ into smaller molecules and produces _______ ATP molecules.
Where does glycolysis happen?
If no oxygen is present then step 2 is fermentation:
Step 2: Fermentation (Anaerobic Respiration)
– happens in the ___________
Does not make any new ___________, but recycles the materials needed for _____________ to continue. (If this didn’t
happen the cell would be stuck and couldn’t make any more _______)
Fermentation can happen 2 different ways:
1. Alcoholic Fermentation – happens in _________. The products of ____________ break down into _______
________ and ethyl alcohol.
How is this used in industry?
2. Lactic Acid Fermentation – happens in your ____________ when you exercise because they are not supplied
with enough ________________. The products from _____________ are broken down into lactic acid and
_______. This can build up in your muscles and it causes them to _________. When __________ is present they
will switch back to oxidative respiration and break it down.
If OXYGEN IS PRESENT, then the Krebs Cycle and Electron Transport will occur causing 36 ATP to be produced.
7