BIOLOGY CH9PPTOL
NAME______________________
COMPLETE ALL QUESTIONS AND BLANKS - 1 POINT DEDUCTION FOR EACH INCORRECT OR MISSED ANSWER
25POINTS
Chapter 9 Photosynthesis and Cellular Respiration
Section 1: Energy in Living Systems
CHEMICAL ENERGY
Organisms use and store energy in the chemical bonds of organic compounds.
Almost all of the energy in organic compounds comes from the SUN.
Organisms require a constant source of energy.
Energy is needed for organisms to maintain their homeostasis.
Homeostasis is the process of maintaining internal order and balance even when the _______________________ changes.
Q1. GIVE A SPECIFIC EXAMPLE OF HOMEOSTASIS IN A LIVING ORGANISM
PHOTOSYNTHESIS
CELLULAR RESPIRATION
Photosynthesis is the process by which plants, algae, and
Cellular Respiration is the process by which all living
some bacteria use sunlight, carbon dioxide, and water to
things*use ________________________ and oxygen to
produce glucose and oxygen.
produce carbon dioxide and water and the molecule ATP
Q2. GIVE AN EXAMPLE OF AN ORGANISM THAT DOES NOT USE CELLULAR RESPIRATION FOR ENERGY.
METABOLISM AND THE CARBON CYCLE
How is an organism’s metabolism related to the carbon cycle?
Metabolism involves using energy to build organic molecules or breaking down organic molecules in which energy is stored.
Organic molecules contain CARBON. Therefore, an organism’s metabolism is part of ____________________ carbon cycle.
Q3. BESIDE CELL RESPIRATION AND PHOTOSYNTHESIS WHAT OTHER CHEMICAL REACTION IS
PART OF THE CARBON CYCLE? WRITE THE GENERAL EQUATION HERE
METABOLISM AND THE CARBON CYCLE
Energy enters an ecosystem when organisms use Light during Photosynthesis to convert CO2 + H20 into C6H12O6 + O2
In Cellular Respiration, cells turn C6H12O6 + O2 into CO2 + H20 molecules and produce energy in the form of _________ .
ATP (Adenosine TriPhosphate),is the main energy source for cell processes.
Q4. GIVE A SPECIFIC EXAMPLE OF A CELLULAR PROCESS THAT USE ATP.
TRANSFERING ENERGY -How is energy released in a cell?
In cells, chemical energy is gradually released in a series of chemical reactions that are assisted by ____________________.
In chemical reactions, energy can be absorbed and released during the breaking and forming of bonds.
Enzymes are proteins that act as catalysts in biochemical reactions.
Q5. NAME AN ENZYME WE HAVE DISCUSSED IN CLASS AND GIVE ITS FUNCTION.
ATP
When cells break down food, some energy is lost as __________________. Much of the remaining energy to make ATP.
ATP is a portable form of energy “currency” inside cells. ATP is a nucleotide made up of a chain of 3 phosphate groups.
When the bond of the 3rd phosphate group is broken, energy is released, producing ADP.
Q6. IS THE LOSS OF A PHOSPHATE FROM ATP AN EXOTHERMIC OR ENDOTHERMIC REACTION?
ATP SYNTHASE
ATP synthase is an ____________________ that catalyzes
the synthesis of ATP,
It recycles ADP by bonding a 3rd phosphate group to the
molecule.
Q7. WHAT DOES ATP-SYNTHASE CARRY?
ATP synthase acts as both an enzyme and a carrier protein
for hydrogen ions.
The flow of H+ ions through ATP synthase powers the
production of ATP.
HYDROGEN ION PUMPS
In Chloroplasts and Mitochondria, a series of molecules The Electron Transport Chain pump H+ ions across the membrane.
The Electron Transport Chain uses energy released from electron carriers, such as NADH and NADPH, to pump H + ions and
create a _______________________ gradient.
Q8. HOW DO CHLOROPLAST AND MITOCHONDRIA USE THE H+ION CONCENTRATION GRADIENT?
Section 2: Photosynthesis KEY IDEAS
What is the role of pigments in photosynthesis?
What are the roles of the Electron Transport Chains?
How do plants make sugars and store extra unused energy?
What are the 3 Environmental factors that affect Photosynthesis?
HARVESTING LIGHT ENERGY
What is the Role of Pigments in Photosynthesis?
In plants, light energy is harvested by ______________________ that are located in the thylakoid membrane of Chloroplasts.
Q9. WHAT TYPE OF MACROMOLECULES ARE PIGMENTS?
PHOTOSYNTHESIS
Photosynthesis is the process that provides energy for almost all life.
Chloroplasts are the organelles that convert light energy into chemical energy.
Within the inner membrane of the chloroplast, is the Stroma that contains the _____________________________ membrane.
This membrane produces flat, disc-like sacs called thylakoids that are arranged in stacks and contain PIGMENTS
Q10. WHAT EVIDENCE IN CHLOROPLASTS SUPPORTS THE ENDOSYMBIONT HYPOTHESIS?
PHOTOSYNTHESIS
Light is a form of electromagnetic radiation, energy that can travel through empty space in the form of _________________.
Sunlight contains all of the wavelengths of visible light which we see as different colors.
Q11. WHAT IS THE SPEED OF LIGHT?
PHOTOSYNTHESIS
A pigment is a substance that absorbs certain wavelengths (colors) of light and reflects all of the others.
Chlorophyll A and B are green pigments in chloroplasts that absorb light energy to start photosynthesis.
They absorb mostly blue and red light and reflects green and yellow light, which makes plants appear __________________.
Plants also have pigments called Carotenoids which help plants absorb additional light energy.
When light hits a thylakoid, energy is absorbed by many pigment molecules and eventually transferred to electron carriers.
Q12. WHICH COLOR ARE THE CAROTENOIDS? WHEN CAN YOU SEE THEM EASILY?
ELECTRON TRANSPORT CHAINS
What are the roles of the electron transport chains?
During photosynthesis, 1 electron transport chain provides energy to make ATP, the other provides energy to make NADPH.
ELECTRON TRANSPORT CHAINS- The Light Reactions
Step 1: Electrons excited by light leave the chlorophyll. An enzyme called Hydrolase splits water to replace these electrons.
Oxygen gas is formed and released into the atmosphere.
Step 2: Excited electrons transfer some of their energy to pump H+ions into the thylakoid.
This process creates a concentration gradient across the thylakoid membrane.
Step 3: The energy from diffusion of H+ions through the channel portion of ATP synthase is used to catalyze a reaction in which a
phosphate group is added to a molecule of ADP, producing ATP.
Step 4: Light excites electrons in another chlorophyll molecule.
The electrons are passed on to the second chain and replacedby the de-energized electrons from the first chain.
Step 5: Excited electrons combine with H+ions and NADP+to form NADPH.
Q13. WHY ARE THESE REACTIONS CALLED THE LIGHT REACTIONS?
Q14. WHAT ARE THEIR INPUT AND NET OUTPUT?
PRODUCING SUGAR – The Dark Reactions – The Light Independent Reactions – The Calvin Cycle
How do plants make sugars and store extra unused energy?
In the final stage of photosynthesis, ATP and NADPH are used to produce C6H12O6 from CO2 .
The first two stages of photosynthesis depend directly on light because light energy is used to make ATP and NADPH.
The use of carbon dioxide to make organic compounds is called carbon dioxide fixation, or CARBON FIXATION.
The reactions that fix carbon dioxide are light-independent reactions, sometimes called dark reactions.
The most common method of carbon fixation is the ________________________________________.
Atmospheric CO2 is combined with other compounds to produce C6H12O6. ATP and NADPH supply the energy required.
Q15. WHY ARE THESE REACTIONS CALLED THE DARK REACTIONS?
Q16. WHAT ARE THEIR INPUT AND NET OUTPUT?
PHOTOSYNTHESIS the Short and sweet version
CO2 + H20  + SUNLIGHT C6H12O6 + O2
OCCURS IN THE CHLOROPLAST OF AUTOTROPHS
HAS BOTH LIGHT AND DARK REACTIONS
PHOTOSYNTHESIS : The LIGHT Reactions* Also known as the LIGHT DEPENDENT REACTIONS
CO2 + H20  + SUNLIGHT C6H12O6 + O2 + ATP +
LIGHT REACTIONS- Use light to split H20, make O2 , and
NADPH
a H+ gradient which makes ATP and NADPH
OCCURS IN THE THYLAKOIDS OF CHLOROPLAST
PHOTOSYNTHESIS : The DARK Reactions* Also known as the Light Independent Reactions and or CALVIN CYCLE
CO2 + H20 + ATP + NADPH  C6H12O6 + O2
THE DARK REACTIONS/CALVIN CYCLE:
OCCURS IN THE STROMA OF CHLOROPLAST
Use CO2 , (+ ATP + NADPH) to make C6H12O6 !!
FACTORS THAT AFFECT PHOTOSYNTHESIS
3 ENVIRONMENTAL FACTORS THAT AFFECT PHOTOSYNTHESIS
LIGHT: The rate of photosynthesis increases as light intensity increases until all pigments in a chloroplast are being used.
CO2: The concentration of carbon dioxide affects the rate of photosynthesis in a way similar to light.
TEMPERATURE: Photosynthesis is most efficient in a certain range of __________________________________.
Q17. WHY IS THE GRAPH OF TEMPERATURE DIFFERENT FROM THAT OF LIGHT?
Section 3: Cellular Respiration
KEY IDEAS
How does glycolysis produce ATP?
How is ATP produced in aerobic respiration?
Why is fermentation important?
GLYCOLYSIS
How does glycolysis produce ATP?
Glycolysis results in a net gain of 2ATP molecules.
Fats can be broken down to make ATP.
The cells of most organisms transfer energy found in
Proteins and nucleic acids can also be used to make ATP,
organic compounds, such as those in foods, to ATP.
but they are usually used for building important cell parts.
The primary fuel for cellular respiration is _____________.
Q18 WHERE DO YOU GET MOST OF YOUR GLUCOSE FROM?
GLYCOLYSIS
In glycolysis, enzymes break down one six-carbon molecule of glucose into two three-carbon pyruvate molecules.
Glycolysis is the only source of energy for some prokaryotes.
Other organisms use O2 to release more energy from a glucose molecule. Metabolic processes that require O2 are AEROBIC.
In Aerobic Respiration, the pyruvate from glycolysis undergoes a series of reactions to produce more ATP molecules.
Q19. WHERE WOULD YOU FIND PROKARYOTES THAT RELY ON GLYCOLYSIS ONLY?
AEROBIC RESPIRATION How is ATP produced in aerobic respiration?
The total yield of energy-storing products from one time through the Krebs cycle is one ATP, three NADH, and one FADH 2.
Electron carriers transfer energy through the electron transport chain, which ultimately powers ATP synthase.
Organisms such as humans can use oxygen to produce ATP efficiently through aerobic respiration
THE KREBS CYCLE
The first stage of aerobic respiration is the Krebs cycle, a series of reactions that produce electron carriers.
The electron carriers enter an electron transport chain, which powers ATP synthase.
Up to ____________ ATP molecules can be produced from one glucose molecule in aerobic respiration.
The Krebs Cycle
Pyruvate (from glycolysis) is broken down and combined with other carbon compounds.
Each time the carbon-carbon bonds are rearranged during the Krebs cycle, energy is released.
The Electron Transport Chain
The 2nd stage of aerobic respiration takes place in the inner membranes of mitochondria, where the ATP synthase is located.
Electron carriers, produced during the Krebs cycle, transfer energy through the electron transport chain.
Energy from the electrons is used to actively transport hydrogen ions out of the inner mitochondrial compartment.
Hydrogen ions diffuse through ATP synthase, providing energy to produce several ATP molecules from ADP.
At the end of the electron transport chain, electrons combine with an O2 and two H+ to form two water molecules.
If oxygen is not present, the electron transport chain stops.
The electron carriers are not recycled, so the Krebs cycle also stops.
Q20. WHY DO WE BREATHE?
FERMENTATION
Why is fermentation important?
Fermentation enables glycolysis to continue supplying a cell with ATP in anaerobic conditions.
To make ATP during glycolysis, NAD+ is converted to NADH.
Organisms must recycle NAD+ to continue making ATP through glycolysis.
The process in which carbohydrates are broken down in the absence of oxygen is called fermentation.
FERMENTATION
In Animals: During vigorous ANAEROBIC exercise, Lactic Acid Fermentation occurs in the muscles of animals, including
humans. In lactic acid fermentation, pyruvate is converted to lactic acid.
In Yeast: During _________________________ Fermentation, one enzyme removes carbon dioxide from pyruvate.
A second enzyme converts the remaining compound to ethanol, recycling NAD+ in the process.
Q21. HOW DO YOU KNOW IF YOU HAVE DONE ANAEROBIC EXERCISE??
Aerobic Cellular Respiration Summary
In the first stage of cellular respiration, glucose is broken down to pyruvate during glycolysis, an anaerobic process.
Glycolysis results in a net gain of 2ATP molecules for each glucose molecule that is broken down.
In the second stage, pyruvate either passes through the Krebs cycle or undergoes fermentation.
Cells release energy most efficiently when O2 is present because they make more ATP during AEROBIC RESPIRATION.
For each glucose molecule that is broken down 2ATP molecules are made during the Krebs Cycle.
The Krebs cycle feeds NADH and FADH2to the Electron Transport Chain, which can produce 32-34 ATP.
CELLULAR RESPIRATION
C6H12O6 + O2  CO2 + H20 + ATP
OCCURS IN THE MITOCHONDRIA OF ALL CELLS*
Has a few Reactions
Glycolysis
And 2 Major Pathways
The Krebs/TCA/Citric Acid Cycle
Aerobic Reactions – use O2
The Electron Transport Chain
Anaerobic Reactions – don’t use O2
or Fermentation (if there’s no O2 available)
Q22. WHAT EVIDENCE IN CHLOROPLASTS SUPPORTS THE ENDOSYMBIONT HYPOTHESIS?
CELLULAR RESPIRATION: Glycolysis
GLYCOLYSIS
C6H12O6 + O2  2ATP + H2O + 2 Pyruvate
OCCURS IN THE CYTOPLASM!!!
NOT MITOCHONDRIA
ANAEROBIC REACTION – DOESN’T USE O2
In Short: Step 1
Glycolysis (glucose-lysis)
C6H12O62Pyruvate + H2O +2ATP
Q23. WHERE DOES GLYCOLYSIS OCCUR?
CELLULAR RESPIRATION: The Krebs Cycle*
THE KREBS CYCLE(*aka. TCA/Citric Acid Cycle)
2 Pyruvate + O2  CO2 +2NADH + 2FADH2 + 2ATP
OCCURS IN THE MATRIX of MITOCHONDRIA
AEROBIC REACTION –USES O2
In Short: Step 2 The Krebs/TCA Cycle
2 Pyruvate CO2 + 2NADH + 2FADH2 + 2ATP
CELLULAR RESPIRATION: The ELECTRON TRANSPORT CHAIN
The Electron Transport Chain
In Short: Step 3
2NADH+ 2FADH2  H20 + 32-34 ATP
The Electron Transport Chain
OCCURS ON THE CRISTAE OF THE MITOCHONDRIA
2NADH + 2FADH2H20 + 32-34ATP
Uses a Hydrogen Ion gradient to make ATP!
Q24. WHERE ELSE ARE H+ CONCENTRATION GRADIENTS USED TO MAKE ATP?
CELLULAR RESPIRATION: if theres no O2
Organisms use Glycolysis then Fermentation!!
ANAEROBIC RESPIRATION
aka Fermentation
In Animals 2 Pyruvate
Lactic Acid
+ 2ATP
In Yeast
2 Pyruvate
Ethanol
+ 2ATP
In Short: UNDER ANEROBIC CONDITONS
Step 1: Glycolysis
Step 2: Fermentation
Q25. ON A SCALE OF 1-10 HOW DIFFICULT IS CELL RESPIRATION AND PHOTOSYNTHESIS