Carbohydrate Metabolism

cellular respiration

is a cellular process that breaks down organic molecules to obtain the energy needed to produce ATP molecules for metabolic reactions

aerobic process

Cellular respiration is an aerobic/anaerobic process

NAD+ (nicotinamide adenine dinucleotide)

As a coenzyme used in oxidation–reduction, it is: • Oxidized when it gives up electrons. • Reduced when it accepts electrons.

FAD (flavin adenine dinucleotide)

Also a coenzyme of oxidation–reduction. • Sometimes used instead of NAD + • Accepts two electrons and two hydrogen ions to become FADH2.

carbohydrates

your body’s main source of fuel. They give you the energy you need to function

1. glycolysis 2. preparatory (prep) reaction 3. citric acid cycle 4. electron transport chain

Phases of Cellular Respiration

Glycolysis

is the breakdown of glucose into two molecules of pyruvate.

• It occurs in the cytoplasm

. • ATP is formed.

• It does not utilize oxygen (anaerobic)

Preparatory (prep) reaction

Both molecules of pyruvate are oxidized and enter the matrix of the mitochondria.

• Electron energy is stored in NADH.

• Two carbons are released as CO2 (one from each pyruvate)

. • It does utilize oxygen (aerobic).

Citric acid cycle

Occurs in the matrix of the mitochondrion and produces NADH and FADH2 .

• A series of reactions, releases 4 carbons as CO2 .

• Turns twice per glucose molecule (once for each pyruvate).

• Produces two immediate ATP molecules per glucose molecule

. • It does utilize oxygen (aerobic).

Electron transport chain (ETC)

• A series of carriers on the cristae of the mitochondria. • Extracts energy from NADH and FADH2 . • Passes electrons from higher to lower energy states. • Produces 32 or 34 molecules of ATP by chemiosmosis. • It does utilize oxygen (aerobic).

in cytoplasm and outside the mitochondria

where does glycolysis occur

10

glycolysis consists of ____ reactions

aerobic respiration.

If O2 is available to the cell, pyruvate enters the mitochondria for ______

anaerobic respiration

if O2 is not available to the cell, pyruvate stays in the cytoplasm and undergoes fermentation _________

Lactic Acid

________ fermentation occurs in anaerobic bacteria & animal cells.

Alcohol

_________fermentation occurs in microorganisms, such as yeast and plant cells.

Fermentation

is an anaerobic process that reduces pyruvate to either lactate or alcohol and CO

Alcoholic fermentation

carried out by yeasts, produces carbon dioxide and ethyl alcohol. • Used in the production of alcoholic spirits and breads.

Lactic acid fermentation

, carried out by certain bacteria and fungi, produces lactic acid (lactate). • Used commercially in the production of cheese, yogurt, and sauerkraut

preparatory (prep) reaction

________________ connects glycolysis to the citric acid cycle.

Citric Acid Cycle

Also called the Krebs cycle or TCA (tricarboxylic acid) cycle.

mitochondria 

where does the Citric Acid Cycle

Electron Transport Chain

Occurs in the Cristae—mitochondria. On plasma membrane in Aerobic prokaryotes.

Chemiosmosis

The electron transport chain complexes pump H+ from the matrix into the intermembrane space of the mitochondrion. • H+ therefore becomes more concentrated in the intermembrane space, creating an electrochemical gradient

catabolism

Degradative reactions ______ break down molecules.

anabolism

Synthetic reactions ______ build molecules.

Tend to be endergonic (consume energy).

Catabolism

Glucose is broken down in cellular respiration. Fat breaks down into glycerol and three fatty acids.

Anabolism

All metabolic compounds are part of the metabolic pool. Intermediates from respiratory pathways can be used for anabolism.