AP Bio Chapter 9 Vocab

ATP

Adenosine Triphosphate

energy currency of the cell - stores energy that can be used to do cellular work

Catabolic

breaks down cellular structures

harvests energy stored in food or fat cells

Digestion

break down of food into molecules that are small enough for your body to absorb

provide nutrients for respiration

aerobic respiration

process to convert stored energy (glucose) to ATP when oxygen is present

O2 is the final electron acceptor in the ETC

Anaerobic respiration

method of harnessing chemical energy without oxygen; typically only done in prokaryotes

final electron acceptor in ETC is another inorganic molecule less electronegative compared to oxygen

Faculative Anaerobes

Use aerobic respiration most of the time but can function without O2 through fermentation

• muscle cells

Obligate anaerobes

Cannot function in the presence of O2

Fermentation

catabolic reaction that continously oxidizes NADH to form NAD+ and transfers electron to pyruvate (or pyruvate derivative) that can fuel glycolysis

happens in the cytosol of the cell and produces 2 ATP

Ethanol / Ethyl Alcohol

product of Alcohol Fermentation that is performed by yeast and bacteria

Lactate / Lactic Acid

Product of Lactic Acid fermentation

done by bacteria, fungi, & human muscle cells

Autotrophs

organisms that create their own organic molecules from inorganic molecules

photoautotrophs

use light energy to make food

chemotrophs

use other methods to other than light to make food

Heterotrophs

organisms that gain energy by breaking down other organisms

Substrate-level phosphorylation

ATP forms through direct transfer of organic phosphate (created during reaction) to ADP using enzyme

- glycolysis and Kreb’s Cycle

Oxidative Phosphorylation

Process that combines P and ADP to make ATP using energy from the redox reactions of the ETC

Glycolysis

process to convert Glucose into Pyruvate

First step of Respiration that happens in cytosol

nets 2 ATP

Nicotimide Adenine Dinucleotide (NAD+)

electron acceptor that converts to NADH and shuttles the electrons to where it needs to go (ETC)

phosphofructokinase

3rd enzyme of glycolysis that is key for regulating the production of ATP in the cell based on the inhibition of other molecules

Pyruvate

product of glycolysis that is where most of the energy from glucose gets stored.

ionized form of pyruvic acid

Acytel-CoA

product of pyruvate oxidation

links glycolysis and citric acid cycle

Citric Acid Cycle / Kreb’s Cycle

converts Acetyl-CoA to regenerate oxaloacetate in the mitochondrial matrix

Citrate synthase

first enzyme in citric acid cycle that limits the rate of production in the cycle

provides citrate from acetyl CoA which in high amounts inhibits phosphofructokinase

electron transport chain (ETC)

transfer of electron down a chain of organic molecules (redox reactions) found in cristae until it gets to O2. Releases energy that can be used to make a proton gradient between intermembrane space and matrix

NADH Dehydrogenase

Enzyme that removes 2H from NADH to form NAD+

First complex in the electron transport chain

Cytochromes

protein containing a heme (iron) prosthetic group that accepts and transfers electron in the ETC

Chemiosmosis

Process in which energy stored in energy gradient after ETC is used to drive ATP synthesis using enzyme ATP synthase

ATP Synthase

enzyme that makes ATP using energy from a proton gradient between the mitochondrial innermembrane space (high concentration) and matrix (low concentration)

Beta-oxidation

break down of fatty acids into 2-carbon fragments that can enter the citric acid cycle as Acetyl-CoA