Module 3 Cell Bio Vocab

Aerobic respiration

Oxygen is used as a recipient to break down sugars to produce ATP (this process is also called cellular respiration)

Anaerobic respiration

Other molecules, such as sulfur or nitrogen, are used to breakdown sugars

Fermentation

Inefficient breakdown of sugars without oxygen

Cellular (aerobic) respiration

The process by which sugar and oxygen are used to generate ATP in cells

Photophosphorylation (photosynthesis)

Light energy is used to power the phosphorylation of ADP via the electron transport chain

Substrate level phosphorylation

A molecule transfers a phosphate directly to ADP rather than coupling an inorganic phosphate (Pi); occurs during glycolysis and Krebs cycle

Mitochondria

Double membrane-enclosed structures which generate ATP (energy) in all types of eukaryotic cells by cellular respiration, have their own ribosomes and DNA

The main sets of reactions that occur during cellular respiration

Glycolysis, Krebs cycle, and oxidative phosphorylation

Glycolysis

A metabolic pathway step that converts one glucose (a 6-carbon sugar, C6H12O6) into two molecules of pyruvic acid (3-carbon simple compound, C3H4O3), includes the energy investment phase and energy payoff phase

Energy investment phase

The cell uses 2 ATP to rearrange glucose into a form that maximizes payoff in the next phase of glycolysis

Energy payoff phase

4 ATP and 2 NADH molecules are generated during this phase; the product of this step is pyruvate, which will proceed on to the next step of cellular respiration, unless oxygen is absent

Krebs cycle

A metabolic pathway step which combines acetyl CoA (a 2-carbon molecule) with oxaloacetate (a 4-carbon molecule) to generate citric acid, as well as high energy cofactors (NADH and FADH2), ATP, and CO2

Oxidative phosphorylation

The last step of cellular respiration where ATP is generated by chemiosmosis of hydrogen ions (H+) in the electron transport chain (ETC)

Electron transport chain

A series of multi-protein complexes which alternate between reduced and oxidized states as they accept and donate electrons

Lactic acid fermentation

The type of fermentation where pyruvic acid is converted into lactic acid, resulting in the generation of NAD+ molecules; done by some prokaryotes and many eukaryotes

Alcohol fermentation

The type of fermentation where pyruvic acid is converted into ethanol, resulting in the generation of NAD+; done by some bacteria and yeast

Fermentation tests

Used to identify what end products are generated through bacteria fermentation from each carbohydrate

Muscle fatigue

The physiological inability to contract despite continued stimulation

The two ways muscle fibers are classified

Speed of contraction (fast/slow) and the metabolic pathway used for ATP synthesis (oxidative or glycolytic/fermentative)

Glycogenesis

Formation of glycogen when glucose supplies exceed cellular need for ATP

Glycogenolysis

Breakdown of glycogen in response to low blood glucose

Gluconeogenesis

Process of forming sugar from non-carbohydrate molecules

Fat Catabolism

Fats are broken down in lipolysis into glycerol (used in glycolysis) and fatty acids (which are used to make acetyl CoA), which are then broken down by a process called beta-oxidation

Protein catabolism

Proteins are digested into amino acids, where the amino groups feed glycolysis or the Krebs cycle

Glycerol pathway

The fat catabolism pathway where glycerol enters the glycolysis pathway

Fatty acids pathway

The type of fat catabolism pathway where fatty acids undergo beta-oxidation to become acetic acid fragments, which are used to generated acetyl CoA

Lipogenesis

Excess glycerol and fatty acids are converted to form triglycerides; the breakdown is referred to as lipolysis; glucose is easily converted to fat (primary means of long-term storage of energy)