Respiration- H

I) General

Respiration- any process that releases energy from food and stores it in ATP for use by the cell

Respiration- "burning food"

Respiration is controlled by respiratory enzymes so the energy is released a little at a time (unlike burning)

All cells respire

Aerobic respiration - cellular respiration- uses oxygen in the process

Anaerobic respiration- does not use oxygen

II) Anaerobic Respiration - 2 parts: glycolysis and fermentation

1) Glycolysis (break down sugar)- this releases energy

Glucose---------> 2 Pyruvic acid + Hydrogen (stored on NAD) + energy (stored in 2 ATP)

2) Fermentation- this gets rid of the hydrogen from glycolysis

There are 2 ways to do this

A) Lactic Acid Fermentation- pyruvic acid and hydrogen are combined to form lactic acid

This is done by the bacteria that cause milk to sour and used to make sour cream, yogurt

This is also done by muscle cells not getting enough oxygen.

Lactic acid builds up- burning pain This is called building an oxygen debt

Heart attack- heart muscle lacks oxygen

B) Alcoholic fermentation- pyruvic acid and hydrogen are combined to make ethyl alcohol and carbon dioxide

This is done by yeast and other micro-organisms

This is used to make beer, wine etc.

The carbon dioxide is what makes bread dough rise

carbon dioxide makes bread dough rise

Either method of anaerobic respiration only releases enough energy for 2 ATP

III) Cellular Resp- Aerobic Resp -Three parts

A)Starts with glycolysis

Glucose ---------> 2 Pyruvic Acid + 4 hydrogen (stored on NAD) + energy (2 ATP)

B) The pyruvic acid enters the Krebs Cycle and is broken apart. Krebs cycle occurs in the mitochondria

Pyruvic acid ---------> CO2 + hydrogen (stored on NAD and FAD) + energy (2 ATP)

(niacin / riboflavin)

The CO2 is released into the environment

Double everything since there are 2 PA per glucose

C) Electron Transport Chain - The hydrogens attached to NAD or FAD have excited electrons- These pass through the ETC where the energy is released and used to push the hydrogens through a membrane inside the mitochondria. The energy is then captured as they pass back through (chemiosmosis) and stored in ATP. The hydrogens and electrons are then combined with oxygen to form water.

The membranes in the mitochondria are called cristae (they are the "ribs" seen using the electron scope)

Krebs Cycle and ETC occur in the mitochondria of cells

VI) General equation for Cellular Resp

C6H12O6 + 6 O2 ------------> 6 CO2 + 6 H2O + Energy (38 ATP)

VIII) Other Stuff

A)Removing hydrogen and combining it with oxygen is where most of the energy is released. Since molecules of fats have more hydrogen than glucose, more energy can be released. We say fats have more calories.

B)Fats can be burned like glucose in respiration since they are made of the same three elements- C, H, O

Amino acids must have the nitrogen removed before they can be burned. This is called deamination.

Once the nitrogen is removed, it is used to make nitrogen waste which is removed.

In humans, nitrogen waste is urea.

C) FAD and NAD are called co-enzymes because they help an enzyme do its job-

The enzyme is a dehydrogenase- something that removes hydrogen. NAD and FAD are temporary hydrogen acceptors.

Oxygen is the final hydrogen acceptor in cellular respiration