Making Energy

TEKS 4.B Students will…

investigate and explain cellular processes, including homeostasis, energy conversions, transport of molecules, and synthesis of new molecules

9.B Students will…

compare the reactants and products of photosynthesis and cellular respiration in terms of energy and matter

Aerobic Cellular Respiration All eukaryotic organisms have mitochondria,

which means they all perform cellular respirationto gain energy (ATP)

A catabolic process – destroying molecules

Cells obtain energy (ATP) from glucose

C6H12O6 + 6O2 6H2O + 6CO2 + 36/38 ATP

Aerobic Cellular Respiration

Breakdown of Aerobic Respiration There are FOUR main parts of respiration

1. Glycolysis – always occurs

1. Splitting of glucose

2. Occurs in the cytoplasm (just outside the mitochondria)

3. Does not require oxygen (anaerobic)

4. Makes 2 ATP

2. Grooming Phase

3. Krebs Cycle

4. Electron Transport Chain (ETC)

Breakdown of Aerobic Respiration There are FOUR main parts of respiration

1. Glycolysis

2. Grooming Phase – a transition

1. Migration from cytoplasm to the mitochondria

2. Occurs when oxygen is PRESENT (aerobic)

3. Results in 2 CO2 (NO energy made)

3. Krebs Cycle

4. Electron Transport Chain (ETC)

Breakdown of Aerobic Respiration There are FOUR main parts of respiration

1. Glycolysis

2. Grooming Phase

3. Krebs Cycle

1. Occurs in the mitochondria

2. Occurs when oxygen is PRESENT (aerobic)

3. Makes 2 ATP and 4 CO2

4. Electron Transport Chain (ETC)

Breakdown of Aerobic Respiration There are FOUR main parts of respiration

1. Glycolysis

2. Grooming Phase

3. Krebs Cycle

4. Electron Transport Chain (ETC)

1. Occurs in the mitochondria

2. Occurs when oxygen is PRESENT (aerobic)

3. Makes approximately 34 ATP!!!

Breakdown of Aerobic Respiration

Process CO2 ATP

Gycolysis 0 2

Grooming 2 0

Kreb’s Cycle 4 2

ETC 0 34

TOTAL 6 38

Aerobic Cellular Respiration

What if there is no oxygen?

Glycolysis does not need oxygen, so it ALWAYS happens (in the cytoplasm)

If oxygen is PRESENT, glycolysis is followed by the grooming phase, Kreb’s Cycle, and ETC as already discussed (in the mitochondria) This is called aerobic respiration

If oxygen is NOT PRESENT, then glycolysis is followed by fermentation (in the cytoplasm) This is called anaerobic respiration

What if there is no oxygen? Fermentation produces MUCH LESS energy

than aerobic respiration!!!

There are two kinds of fermentation – alcoholic fermentation and lactic acid fermentation

Alcoholic Fermentation Occurs in plants and fungi

Produces bread, beer, and wine

Glucose is broken down to produce

2 ATP

2 CO2

2 Ethanol

Lactic Acid Fermentation Occurs in animals

Causes pain in muscles after a workout

Glucose is broken down to produce

2 ATP

2 Lactic Acid Molecules

Using ATP ATP releases its energy when the bond between the

second and third phosphate group is broken

This breaking converts ATP into ADP, which can then have a third phosphate group added to it, turning it back into ATP

It should be noted Only about 30% the energy

released from glucose by cellular respiration is captured in ATP

Some of the energy is converted to heat (thermal energy), which we give off

The MINIMUM yield of ATP for each molecule of glucose is 29

Cellular Respiration Wrap-UP

Comparing Photosynthesis & Respiration

Comparing Photosynthesis & Aerobic Cellular Respiration

Matter versus Energy Matter

Carbon Dioxide

Oxygen

Glucose (sugar)

Water

Energy Sunlight (radiant)

ATP (chemical)