Cellular Respiration and Photosynthesis: The Energy Cycles of Life
Why ATP is Useful to Cells
ATP can easily release and store energy by breaking and re-forming the bonds between its phosphate groups.
Energy
The ability to do work
ATP Stands for…
Adenosine triphosphate
ATP Consists of…
Adenine, a 5-carbon sugar called ribose, and three
phosphate groups
ADP Stands for
Adenosine diphosphate
Difference Between ATP and ADP
ADP has two phosphate groups, while ATP has three phosphate groups.
(ATP, ADP) Can Contain More Energy
ATP
Cells Release Energy by…
Breaking the bonds between the second and third phosphate groups.
Cells Use ATP by…
Carrying out active transport.
ATP Powers…
Movement (An example is the powering of cilia and flagella)
ATP (Is, Is Not) Very Good as Storing Energy
Is not
Chemical Formula for Glucose
C₆H₁₂O₆
What Happens During the Process of Photosynthesis
Plants convert the energy of sunlight into chemical energy stored in the bonds of carbohydrates.
Heterotrophs
Organisms that obtain food by consuming other living things
Autotrophs
Organisms that make their own food
Photosynthesis
The process by which autotrophs use the energy of sunlight to produce high-energy carbohydrates that can be used for food
The Role Pigments Play in the Process of Photosynthesis
Photosynthetic organisms capture energy from sunlight with pigments.
Energy From the Sun Travels to Earth in the Form of —–
Light
Our Eyes See the Different Wavelengths of the ——- Spectrum
Visible
Pigments
How plants gather the sun’s energy with (light-absorbing molecules)
Chlorophyll
The plant’s principal pigment
Thylakoids
Saclike photosynthetic membranes in chloroplasts
Granum
Thylakoids are interconnected and arranged in these types of stacks (plural version is grana)
Where Pigments Are Located
The thylakoid membranes.
Stroma
The fluid portion outside of the thylakoids
Electron Carrier Molecules
A compound that can accept a pair of high-energy electrons and transfer them, along with most of their energy, to another molecule.
Chemical Equation of Photosynthesis
Light + 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
Photosynthesis Involves — Sets of Reactions.
Two
The First Set of Reactions Is Known as the —– ——— ———
Light-dependent reactions
Light-Dependent Reactions
Require the direct involvement of light and light-absorbing pigments.
Light-Independent Reactions
ATP and NADPH molecules produced in the light-dependent reactions are used to produce high-energy sugars from carbon dioxide.
Light (Is, Is Not) Required to Power the Light-Independent Reactions.
Is not
NADP+
A carrier molecule. (nicotinamide adenine dinucleotide phosphate)
Photosystem
Clusters of chlorophyll and proteins in thylakoids
Photosystem II Comes (First, Second)
First
Electron Transport Chain
A series of electron carriers that shuttle high-energy electrons during ATP-generating reactions
What Plants Get Out of Photosystem II
Hydrogen (We get oxygen from this too. Plants don’t care about the oxygen and get rid of it)
ATP Synthase
An enzyme that catalyzes the linking together of two molecules, without the direct involvement of ATP (This protein forms ATP)
Chemiosmosis
A process that enables light-dependent electron transport to produce not only NADPH (at the end of the electron transport chain), but ATP as well.
If You Put 12 CO₂ Molecules in Carbon Fixation, How Much Glucose Do You Get Out (Part of the Calvin Cycle)
Four (Divide however many molecules you have by three)
How Organisms Get Energy
Food
Calorie
The amount of energy needed to raise the temperature of 1 gram of water by 1 degree Celsius.
Kilocalorie
1 Calorie (Spelling counts. Also 1000 calories)
Cellular Respiration
The process that releases energy from food in the presence of oxygen.
Cellular Respiration Equation
6 O₂ + C₆H₁₂O₆ → 6 CO₂ + 6 H₂O
Main Stages of Cellular Respiration
Glycolysis, Krebs cycle, electron transport chain
Where Glycolysis Takes Place
Cytoplasm
Where the Krebs Cycle and Electron Transport Chain Takes Place
Mitochondria
What Organelle Is Involved in Cellular Respiration?
Mitochondria
What Is Released in the Krebs Cycle
CO₂ and energy
What Cycle Does Most of the Energy Come From?
Electron transport chain
Output of the Electron Transport Chain
Water, oxygen, and energy
Aerobic
Pathways of cellular respiration that require oxygen
Does Glycolysis Need Oxygen?
No
Anaerobic
Does not directly require oxygen nor does it rely on an oxygen-requiring process to run
What Is the Relationship Between Photosynthesis and Cellular Respiration (This Will Probably Be a Short Answer on the Test)
Photosynthesis removes carbon dioxide from the atmosphere, and cellular respiration puts it back.
Glycolysis
A metabolic process that breaks down carbohydrates and sugars through a series of reactions to either pyruvic acid or lactic acid and release energy for the body in the form of ATP
Our Goal Is to Get _____ ATP per Glucose
38
PGAL
A three-carbon molecule formed in the second step of glycolysis
Difference Between PGAL and Pyruvate
One phosphate
First Step of Glycolysis
Breaking of bonds
Second Step of Glycolysis (Investment Phase)
2 PGAL formed
Third Step of Glycolysis (Pay-off Phase)
NAD+ and 2ADP added on each side to form NADH and four ATP. There is only a net gain of 2ATP though because it takes some energy to make it. (At the beginning)
Fourth Step of Glycolysis
2 Pyruvate formed
Net Gain of Glycolysis
2 ATP, 2 NADPH, and 2 Pyruvate
What Is Sent Into the Kreb Cycle
Acetyl CoA (2C molecule. You get rid of 1C from the pyruvate and it becomes CO₂)
What Happens During the Krebs Cycle?
Pyruvic acid is broken down into CO₂ in a series of energy-extracting reactions
The Krebs Cycle Is Also Known as…
Citric Acid Cycle
Net Gains in the Krebs Cycle
2 FADH₂, 6 NADH, and 2 ATP
What Is Yielded From the Electron Transport Chain in Cellular Respiration
H₂O and ATP