Cellular Respiration and Biofuels Lecture Notes

Comprehensive vocabulary flashcards covering the processes of aerobic and anaerobic cellular respiration, mitochondrial anatomy, factors affecting respiration rates, and the production and implications of biofuels.

Cellular Respiration

The process used by organisms to produce $ATP$, the immediate form of energy that can be used by a cell.

Glucose

The primary source of energy used to drive cellular respiration in all organisms except Archaea.

Aerobic Respiration

Cellular respiration that occurs in the presence of oxygen.

Anaerobic Respiration

Cellular respiration that occurs in the absence of oxygen; also known as fermentation.

Glycolysis

The first process in cellular respiration, occurring in the cytosol, which involves 10 chemical reactions to convert glucose into two molecules of pyruvate.

Pyruvate

A three-carbon molecule that is the output of glycolysis.

NADH

A loaded coenzyme molecule produced when $NAD^+$ accepts $H^+$ ions and electrons during respiration.

Cristae

The folds of the inner membrane of the mitochondria.

Mitochondrial matrix

The fluid inside the mitochondria where the Krebs cycle occurs.

Acetyl-CoA

A loaded co-enzyme derived from pyruvate that enters the Krebs cycle.

Krebs Cycle

A series of biochemical reactions occurring in the mitochondrial matrix that produces $ATP$, $NADH$, $FADH_2$, and $CO_2$.

Electron Transport Chain

The final set of reactions occurring on the inner mitochondrial membrane where electrons are transferred to cytochromes and finally accepted by oxygen.

ATP synthase

A protein structure that protons move through to generate $ATP$ using energy from the electron transport chain.

Obligate anaerobes

Organisms that perform anaerobic respiration all the time and live in anoxic environments where no oxygen is available.

Facultative anaerobes

Organisms that can switch between anaerobic and aerobic respiration depending on oxygen availability.

Lactic Acid Fermentation

A type of anaerobic respiration occurring in muscle tissue where pyruvate is converted to lactate (and eventually lactic acid) to regenerate $NAD^+$.

Alcoholic Fermentation

A type of anaerobic respiration performed by yeast where pyruvate is converted into ethanol and carbon dioxide.

Biomass

Organic material, such as plant and animal material from agriculture or forestry, used to produce biofuels.

Bioethanol

A type of biofuel derived from the fermentation of plant sugars.

Biodiesel

A biofuel produced via the formation of fatty acids from natural oils like animal fats and vegetable oil.

Deconstruction

The first step of biofuel production where biomass is treated physically, chemically, or biologically to break down cell walls and increase surface area.

Digestion by enzymes

The second step of biofuel production where broken down biomass is exposed to enzymes like amylase to convert starch and cellulose into glucose.

Purification and dehydration

The final steps of biofuel production where water is removed and ethanol is distilled into a usable liquid fuel.

E10

A common ethanol blend fuel containing $10\%$ ethanol and $90\%$ gasoline.

Enzyme Inhibition

A factor affecting respiration where molecules like cyanide or high levels of $ATP$ (acting as a competitive inhibitor) interfere with enzyme function.