Notesale: Turn your study into money

Document Preview

Extracts from the notes are below, to see the PDF you'll receive please use the links above

---

Cellular Respiration

The chemical process occurring in all cells that
produces energy from “food” chemicals
...

Cellular Respiration happens inside cells – all cells – and is several
chemical reactions which produce “energy” needed by the cells
...


Why cells need energy
Our entire body is made up of cells
...

The specialized roles require the cells to complete specific chemical
reactions – which requires energy
...
These processes also require energy
...

Basal metabolism is the minimum energy required for
enough of these processes to occur to stay alive
...


Catabolism and Anabolism
• The metabolic processes that involve breakdown of
compounds are called catabolic processes – respiration is a
catabolic process
...


Cellular Respiration Chemistry
There are many chemical reactions that make up the entire respiration
cycle and there are both aerobic and anaerobic versions of respiration
...
The food particles
end up broken into simpler “waste” molecules
...


Aerobic Respiration
The most common respiration process (and the most
important for humans) is aerobic respiration of simple sugars
...
The energy produced is stored
in the chemical bonds of ATP molecules
...
The carbon dioxide comes from the carbon-carbon bonds and is
a waste product
...

Glucose is only one possible fuel for respiration
...


Carbohydrates ( like starch in potatoes)

Can be used – but also have to be split up during digestion first
...


Need even more rearranging into the correct
shape for the respiration enzymes
...

Have enough carbons
bonded together to be
used as fuel with more rearranging
...

Adenosine diphosphate gains a third phosphate to become adenosine
triphosphate
...
When ATP is used, the 3rd phosphate
comes off, releasing the energy in that bond for that cell process
...


Adenosine Triphosphate - ATP

Cellular respiration begins in the cytoplasm and
finishes in the mitochondria
...

Remember mitochondria from grade 9?
Mitochondria are sometimes called the “powerhouses” of the cell
because they “make energy”
...
The presence of
cristae increase the surface area available for the chemical processes
of respiration
...


IB Biology version - SL

HL…
...
Without oxygen, cells use other chemical pathways and much fewer
ATP molecules result – but the cell can stay alive (for a while)
...
These organism are adapted to live easily in low oxygen
environments
...


Anaerobic Respiration
Anaerobic respiration is often called fermentation and there are two
types:

Alcohol Fermentation and Lactic Acid Fermentation
Most aerobic organisms can use the lactic acid process
...


Alcoholic Fermentation
C6H12O6  2 CH3CH2OH + 2 CO2 + 118 kJ
Glucose  ethanol + carbon dioxide + energy

See how much less energy is produced (it was over 3000kJ for aerobic)
...


Lactic Acid Fermentation

Again, the reason for less energy production is that the carbon-carbon
bonds in the glucose are not completely broken
...
The lactic acid is a waste product and
must be taken back to the liver for processing
...
If the muscle contraction
process occurs more quickly than oxygen can be delivered, lactic acid
fermentation begins
...
This is called muscle fatigue and the lactic acid must be removed to
the liver and processed – using another process that requires oxygen
...




---