Respiration- CP
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 Resp- occurs in 2 stages; 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 combines the pyruvic acid and the hydrogen (NADH)- this gets rid of the hydrogen
There are two types of fermentation
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- coronary arteries clogged- heart muscle lacks oxygen
B) Alcoholic fermentation- pyruvic acid and hydrogen are combined to make ethyl alcohol and carbon dioide
This done by yeast and other micro-organisms
This is used to make beer, wine etc.
The carbon dioxide released is what 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 ---------> Pyruvic Acid + hydrogen (stored on NAD) + energy (2 ATP)
B) The pyruvic acid enters the Krebs Cycle and is broken apart
Pyruvic acid ---------> CO2 + hydrogen (stored on NAD and FAD) + energy (2 ATP)
(niacin / riboflavin)
The CO2 is released into the environment
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 stored in 34 ATP. The hydrogens are then combined with oxygen to form water
Krebs Cycle and ETC occur in the mitochondria of cells
VII) General equation for Cellular Resp
C6H12O6 + 6 O2 ------------> 6 CO2 + 6 H2O + Energy (38 ATP)
IV) 38 ATP
2 from glycolysis
2 from Krebs Cycle
34 from ETC
Total - 38 ATP (this can vary with different cells)
Removing hydrogen and combining it with oxygen is where most of the energy is released. Since molecules of fats have more hydrogen that glucose, more energy can be released. We say fats have more calories.
Saturated fats have more calories than unsaturated fats because they have the maximum amount of hydrogen.
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.