Chapter 6-7 - Photosynthesis and Cellular Respiration Flashcards
Define photon
A packet of light
What is the equation for photosynthesis? (Word and Chemical)
W: carbon dioxide + water + energy > glucose + oxygen
C: CO2 + H2O + energy > C6H12O6 + O2
What colour is chlorophyll a?
Blue-green
What colour is chlorophyll b?
Yellow-green
Define chlorophyll
The light-absorbing green-coloured pigment that begins the process of photosynthesis.
Define chloroplast
A membrane-bound organelle in green plant and algal cells that carries out photosynthesis.
Define storma
The protein-rich semiliquid material in the interior of a chloroplast
Define thylakoid
A system of interconnected flattened membrane sacs forming a separate compartment within the stroma of a chloroplast.
Define grana
Stacks of thylakoids
Define lamellae
Groups of unstacked thylakoids between grana
Define thylakoid membrane
The photosynthetic membrane within a chloroplast that contains light-gathering pigment molecules and electron transport chains.
Define thylakoid lumen
The fluid-filled space inside a thylakoid
What is ATP and its chemical name?
(Adenosine triphosphate) is a molecule containing three high-energy phosphate bonds that acts as the primary energy-transferring molecule in living organisms.
What is ADP and its chemical name?
(Adenosine diphosphate) is a molecule containing two high-energy phosphate bonds that may be formed by breaking on of the phosphate bonds in ATP
What is NADP+ and its chemical name?
(Nicotinamide dinucleotide phosphate) is a compound that accepts one hydrogen atom and two electrons, forming NADPH; is an electron acceptor
What is NADPH?
NADPH is a compound that donates one hydrogen atom and two electrons to another molecule, to reform NADP+; is an electron donor
What are light-dependent reactions?
Light-dependent reactions are the first set of reactions in photosynthesis in which light energy excites electrons in chlorophyll molecules, powers chemiosmotic ATP synthesis, and results in the reduction of NADP+ to NADPH
What is carbon fixation?
The process of incorporating CO2 into carbohydrate molecules
What is the Calvin cycle?
A cyclic set of reactions occurring in the stroma of chloroplasts that fixes the carbon of CO2 into carbohydrate molecules and recycles coenzymes
What are light-independent reactions?
The second set of reactions in photosynthesis (the Calvin cycle); these reactions do not require solar energy
What is a photosystem?
A cluster of photosynthetic pigments embedded in a thylakoid membrane of a chloroplast that absorbs light energy
What is an electron transport chain?
A series of progressively stronger election acceptors; each time an electron is transferred, energy is released
What is photolysis?
A chemical reaction in which a compound is broken down by light; in photosynthesis, water molecules are split by photolysis.
What is oxidation?
A reaction in which an atom molecule loses electrons
What is reduction?
A reaction in which an atom or molecule gains electrons
What is an ATP synthase complex?
A specialized protein complex embedded in the thylakoid membrane that allows H+ ions to escape from the lumen and uses the resulting energy to generate ATP
Define chemiosmosis
A process for synthesizing ATP using the energy of an electrochemical gradient and the ATP synthase enzyme
What is NADH?
It is an electron carrier which donates electrons in cellular processes. It is the reduced form of NAD+.
What is NAD+?
It is an electron carrier which accepts electrons in cellular processes
What is FADH2?
An electron carrier, donates electrons in cellular processes.
What is FAD+?
An electron carrier, accepts electrons in cellular processes.
What is active transport?
The movement of substances through a membrane against a concentration gradient using membrane-bound carrier proteins and energy from ATP.
What is a sodium-potassium pump?
An active-transport mechanism that pumps sodium and potassium ions into and out of a cell
What is aerobic cellular respiration?
The set of reactions that takes place in the smell in the presence of oxygen and releases energy stored in glucose.
What are the steps of aerobic cellular respiration?
1) Glycolysis
2) Pyruvate oxidation
3) the Krebs cycle
4) the electron transport chain and chemiosmosis
What is anaerobic cellular respiration?
The set of reactions that takes place in the cell in the absence of oxygen and releases energy stored in glucose.
What are the steps anaerobic cellular respiration?
1) Glycolysis
2) Fermentation
Define Glycolysis
A process for harnessing energy in which a glucose molecule is broken into two pyruvate molecules in the cytoplasm of a cell.
What are the products of glycolysis?
2 pyruvates, 2 ATP molecules, 2 NADH molecules and 2 H+ molecules.
What is the mitochondria?
A eukaryotic cell organelle in which aerobic cellular respiration occurs.
What is the mitochondrial matrix?
The fluid that fills the interior space of the mitochondrion.
What is the intermembrane space?
The fluid-filled space between the inner and outer mitochondrial membranes.
What is the Krebs cycle?
A cyclic series of reactions that transfers energy from organic molecules to ATP, NADH and FADH2, and removes carbon atoms as CO2.
Where does the Krebs cycle occur?
The Krebs cycle occurs in the mitochondrial matrix.
What is the role of oxygen in aerobic cellular respiration processes? What happens to if oxygen is not present?
Oxygen acts as the final acceptor of electrons that pass through the electron transport chain. If oxygen is not present then the Krebs cycle, electron transport, and chemiosmosis comes to a halt.
What is oxidative ATP synthesis?
The production of ATP from a series of oxidation reactions.
What is the total theoretical ATP yield of all aerobic respiration processes?
36 ATP molecules.
What is alcohol fermentation?
A form of fermentation occurring in yeast in which NADH passes its hydrogen atoms to acetaldehyde, generating carbon dioxide, ethanol, and NAD+.
What are the steps of alcohol fermentation? What are the final waste products?
1) Glycolysis
2) Fermentation (Recycles some of the products in glycolysis into carbon dioxide and ethanol)
What is lactic acid fermentation?
A form of fermentation occurring in animal cells in which NADH transfers its hydrogen atoms to pyruvate, regenerating NAD+ and lactic acid.
What are the steps of lactic acid fermentation? What are the final waste products?
1) Glycolysis
2) Fermentation (Recycles some products of glycolysis into lactic acid)
What is the VO2 max?
The maximum volume of oxygen, in millilitres, that the cells of the body can remove from the bloodstream in one minute per kilogram of body mass while the body experiences maximal exertion.
What is the lactic acid threshold?
The value of exercise intensity at which lactic acid production increases
Where do light dependent reactions take place?
Light dependent reactions take place on the thylakoid membranes inside the chloroplasts
Where do light independent reactions take place?
In the stroma of the chloroplasts
What is the main function of photosynthesis?
To convert solar energy into glucose.
What is the role of cellular respiration?
To provide cells with required energy for a particular process. The energy must be supplied in the useable form of ATP, and this allows energy to be released gradually.
What does photosynthesis do to carbon dioxide and glucose? How does it happen?
Photosynthesis REDUCES carbon dioxide to glucose. Electrons and hydrogen ions are chemically added to CO2 to produce high energy molecules.
What does cellular respiration do to glucose and CO2? How does it happen?
Cellular respiration releases the energy by OXIDIZING glucose to CO2. Electrons and hydrogen ions are chemically removed from glucose, releasing energy and producing CO2 and H2O.
What happens when ATP loses a phosphate group?
When ATP loses a phosphate group, it forms ADP and releases energy. This energy is used for cellular processes.
What is the fundamental role of cellular respiration?
It is to transfer the energy content of food into the energy content of ATP.
How efficient is cellular respiration? What happens to the other percentage?
Only approx 36% of the energy content of one glucose molecule is converted into the energy of ATP. The remaining 64% is released as heat.
What do NADH and FADH2 have in common?
Both are electron carriers, and they donate electrons in cellular processes.
What happens in oxidation reactions?
Electrons are lost
What happens in reduction reactions?
Electrons are gained.
How many ATP molecules does anaerobic cellular respiration produces?
2 ATP molecules.
How many ATP molecules does aerobic cellular respiration produce?
36 ATP molecules.
What are the products at the end of the Kreb’s cycle?
CO2 as waste product and the energy of the original glucose molecule.
Where is the electron transport chain located?
It is embedded in the inner mitochondrial membrane.
Where does pyruvate oxidation occur?
In the mitochondrial matrix.
Where does glycolysis occur?
In the cytoplasm.
What is the waste product of pyruvate oxidation?
The waste product of pyruvate oxidation is carbon dioxide (CO2)
What is the waste product of the Krebs Cycle?
The waste product of the Krebs cycle is two CO2 molecules.
What is acetyl-CoA?
Acetyl-CoA is a 2 carbon compound derived from pyruvate from glycolysis.
What is oxaloacetic acid?
A 4 carbon bond.
What is created when acetyl-CoA and oxaloacetic acid combine?
Citrate or citric acid is created. (6-carbon molecule)
What do FADH2 and NADH do in the electron transport chain?
They release energy and carry electrons around
Where does chlorophyll absorb light most efficiently from?
The red and blue part of the spectrum.
Where are photosystems located?
In a thylakoid membrane.
