Honors Bio Final

Cellular Respiration

The process by which cells break down glucose using oxygen to release energy (ATP).

Photosynthesis

The process in which plants, algae, and some bacteria convert carbon dioxide and water into glucose and oxygen using light energy.

Overall Balanced Equation for Cellular Respiration

C6H12O6 → 6CO2 + 6H2O + ATP (energy)

Energy Requirement in Cells

Cells need energy to live, grow, repair themselves, and respond to their environment.

Breathing and Cellular Respiration

Breathing gets oxygen into the body and removes carbon dioxide; cellular respiration uses oxygen to make energy and creates carbon dioxide as a waste product.

Redox Reactions

A chemical reaction in which electrons are lost from one substance (oxidation) and added to another (reduction).

Oxidation

The loss of electrons from a substance.

Reduction

The gain of electrons by a substance.

Stages of Cellular Respiration

The stages include glycolysis, the Krebs cycle, and the electron transport chain.

Reactants of Photosynthesis

Carbon dioxide (CO2) and water (H2O).

Products of Photosynthesis

Glucose (C6H12O6) and oxygen (O2).

Reactants of Cellular Respiration

Glucose (C6H12O6) and oxygen (O2).

Products of Cellular Respiration

Carbon dioxide (CO2), water (H2O), and ATP (energy).

Location of Photosynthesis

Occurs in chloroplasts.

Location of Cellular Respiration

Occurs in mitochondria.

Light Energy in Photosynthesis

Requires light energy from the sun.

Energy Release in Cellular Respiration

Releases energy stored in ATP.

Equation for Photosynthesis

Sunlight + 6CO2 + 6H2O → C6H12O6 + 6O2.

Waste Product of Cellular Respiration

Carbon dioxide (CO2).

Support of Breathing for Cellular Respiration

Breathing supports cellular respiration, and cellular respiration depends on breathing.

Chemical Reaction in Redox

Involves the transfer of electrons between substances.

Glycolysis

The metabolic process that converts glucose into pyruvate, producing ATP and NADH.

What process is demonstrated in this image?

Glycolysis, in cellular respiration

Cytosol

The fluid portion of the cytoplasm in cells where glycolysis occurs.

Net production of ATP from each glucose

2 ATP (Net gain); 4 ATP produced, but to ATP are used during earlier steps

NAD+

An electron carrier that is reduced to NADH during glycolysis.

NADH

The reduced form of NAD+, produced when NAD+ gains electrons and hydrogen.

Glucose oxidation

The process by which glucose loses electrons, resulting in the production of NADH.

Pyruvate

The end product of glycolysis, formed from the splitting of a 6-carbon glucose molecule.

Enzyme-catalyzed reactions

The 9 reactions that occur during glycolysis as glucose is converted to pyruvate.

Cleavage

The step in glycolysis where glucose is split into two 3-carbon molecules (G3P).

Energy Payoff Phase

The phase of glycolysis where each 3-carbon molecule is converted into pyruvate, producing 4 ATP and 2 NADH.

Initial energy source

Glucose, which contains chemical energy and is used at the start of glycolysis.

ATP investment

2 ATP are invested early in glycolysis to activate glucose.

High-energy electrons

Electrons stored in NADH, produced during glycolysis when NAD+ is reduced.

ATP generation

4 ATP are generated during the conversion of 3-carbon sugars in glycolysis, resulting in a net gain of 2 ATP.

Mitochondria

The organelle where pyruvate can enter for further ATP production via aerobic respiration.

Oxidation of pyruvate

The process that occurs in the mitochondrial matrix after glycolysis, producing acetyl-CoA and NADH.

The process outlined in the image

Oxidation of pyruvate to Acetyl-CoA, in cellular respiration

Acetyl-CoA

The product formed from the oxidation of pyruvate, which enters the citric acid cycle.

Twice per glucose

The oxidation of pyruvate occurs twice for each glucose molecule, as glycolysis produces two pyruvate.

Decarboxylation

One carbon atom is removed from the pyruvate (a 3 carbon molecule) as CO2, leaving a 2 carbon fragment.

Coenzyme A

The oxidized 2-carbon unit is attached to Coenzyme A, forming acetyl-CoA.

Citric Acid Cycle

A cycle that starts and ends with oxaloacetate (a 4-carbon molecule), allowing it to combine with another acetyl-CoA.

Mitochondrial Matrix

The location where the Krebs cycle takes place.

Oxaloacetate

Regenerated at the end of the citric acid cycle, ready to combine with another acetyl-CoA.

Citric Acid (Citrate)

A 6-carbon molecule formed from the combination of acetyl-CoA and oxaloacetate.

Carbon Dioxide (CO2)

2 CO2 are released as waste from carbon oxidation during the citric acid cycle.

FADH2

1 FADH2 is produced from the reduction of FAD, also carrying electrons.

ATP

1 ATP is formed by substrate-level phosphorylation during the citric acid cycle.

Oxylactate

Regenerated during the cycle, enabling it to repeat.

Electron Transport Chain (ETC)

A series of proteins in the inner membrane of mitochondria that transfer electrons and pump H+ ions.

Inner Membrane

Location of the ETC and ATP synthase.

Intermembrane Space

The space between inner and outer membranes where H+ ions accumulate.

Matrix

The innermost space of the mitochondrion where the Krebs cycle occurs.

Proton Gradient

Created by pumping H+ ions from the matrix into the intermembrane space.

ATP Synthase

An enzyme that uses the flow of H+ ions to phosphorylate ADP + P to ATP.

Oxygen's Role

Oxygen acts as the final electron acceptor in the ETC, combining with low-energy electrons and H+ to form water (H2O).

Cyanide Poisoning

Cyanide inhibits the electron transport chain, preventing ATP production and leading to cell death.

Cyanide

A poison that blocks the electron transport chain (ETC) in mitochondria, halting ATP production and causing cells to die from energy failure.

Cell death

Occurs quickly after ATP depletion, leading to organ failure and death within minutes in high doses.

Alcoholic Fermentation

A type of fermentation that occurs in yeast and some bacteria, producing 2 ethanol and 2 CO2 from glucose.

Lactic Acid Fermentation

A type of fermentation that occurs in mammalian muscle cells and some bacteria, producing 2 lactic acid from glucose.

Fermentation Overview

An anaerobic process that occurs in the cytosol, begins after glycolysis when oxygen is not available, and regenerates NAD+.

NAD+ Regeneration

Occurs via conversion of pyruvate in fermentation and via the electron transport chain (ETC) in aerobic respiration.

ATP Yield in Fermentation

2 ATP is produced per glucose during fermentation.

ATP Yield in Aerobic Respiration

About 30-32 ATP is produced per glucose during aerobic respiration.

End Products of Fermentation

Lactic acid or ethanol + CO2 are produced in fermentation.

End Products of Aerobic Respiration

CO2 and H2O are produced in aerobic respiration.

Location of Fermentation

Occurs only in the cytosol.

Location of Aerobic Respiration

Occurs in the cytosol (glycolysis) and mitochondria (ETC).

Organism Examples for Fermentation

Mammal muscle cells (lactic acid), yeast (alcoholic), lactic acid bacteria (lactic acid), certain prokaryotes (either type).

Elements of Carbohydrates

Carbohydrates are made up of carbon (C), hydrogen (H), and oxygen (O).

Structural Formula of Glucose

C6H12O6 is the structural formula of glucose, a monosaccharide.

Importance of Glucose

Glucose serves as the primary source of energy for cells and is essential for the proper functioning of every organ system.

Monosaccharides, Disaccharides, and Polysaccharides

Monosaccharides are single sugar units, disaccharides are composed of two monosaccharides, and polysaccharides are long chains of monosaccharides.

Monosaccharides

The simplified form of carbohydrates, simple sugar units.

Disaccharides

Made by joining two monosaccharides together through a dehydration reaction (which removes a water molecule).

Polysaccharides

Long chains of many monosaccharides linked together.

Dehydration synthesis

Two monosaccharides (for disaccharides) or many monosaccharides (for polysaccharides) join together.

Hydrolysis

A water molecule is added to break a glycosidic bond.

Starch

Found in: Plants.

Glycogen

Found in: Animals (especially liver and muscles).

Cellulose

Found in: Plant cell walls.

Autotroph

An organism that makes its own food using light or chemical energy.

Heterotroph

An organism that cannot make its own food and must consume organisms for energy.

Chloroplast

An organelle in plant cells where photosynthesis occurs.

Grana

Stacks of flattened sacs called thylakoids in chloroplasts.

Thylakoid

Membrane-bound compartment within chloroplasts where the light-dependent reactions of photosynthesis take place.

Thylakoid membrane

Site of the light-dependent reactions of photosynthesis; contains chlorophyll, photosystems (I and II), electron transport chains, and ATP synthase.

Thylakoid Space (Lumen)

Interior space enclosed by the thylakoid membrane where the proton gradient builds up to power ATP production.

Stroma

Located inside the chloroplast, but outside the thylakoid membranes; site of the Calvin cycle, where carbon dioxide (CO2) is fixed into glucose using ATP and NADPH.

Isotope

Atoms of the same element with different numbers of neutrons, allowing scientists to follow atoms through complex pathways.

Overall equation for photosynthesis

6CO2 + 6H2O + light energy → C6H12O6 + 6O2.

Redox reactions in photosynthesis

Involves the oxidation of water and reduction of NADP+; essential for energy transfer in light-dependent and light-independent reactions.

Water (H2O)

Oxidized in photosynthesis; source of electrons and protons; releases O2.

NADP+

Reduced in light reactions; final electron acceptor that forms NADPH.

CO2

Reduced in the Calvin Cycle; becomes part of glucose.

NADPH

Oxidized in the Calvin Cycle; donates electrons to reduce CO2.

Pigments

Molecules that absorb specific wavelengths of light; capture light energy for photosynthesis.