1. Cells need energy to LIVE!!!
WHAT DO CELLS NEED ENERGY FOR?
Active transport
Cellular Reproduction
Synthesis of macromolecules (Proteins, Lipids, Carbohydrates, Nucleic Acids)
Repair
Specialized cells:
Muscle Cells: contraction
Nerve Cells: electrical impulse
Cells need energy to LIVE!!!
And Much More!

2. THE SUN! SO, WHERE DOES THIS ENERGY COME FROM?
Energy for living things comes from food.
Most of the energy for food comes from
THE SUN!

3. Organisms that use light energy from the sun to produce food are called autotrophs (auto = self)
Ex: plants and some microorganisms (some bacteria and protists)

4. Organisms that CANNOT use the sun’s energy to make food and need to consume food are called heterotrophs.
Ex: animals and most microorganisms

5. Heterotrophs consume autotrophs to take in this energy.
TRAPPING THE SUN’S ENERGY
Photosynthesis:
the energy of sunlight helps to make glucose
This process is done by Autotrophs.
Heterotrophs consume autotrophs to take in this energy.
Reactants (in)
Products (out)

6. Chlorophyll is the pigment inside the chloroplast that absorbs the sun’s light for photosynthesis
As the chlorophyll in leaves decays in the autumn, the green color fades. Other pigments (carotenoids) are then visible.

7. We now know that autotrophs can make glucose from sunlight, water, and carbon dioxide.
Glucose is packed full of energy.
However, this energy is not in a form that our cells can use.
The energy from glucose must be transferred to a molecule called ATP before the cell can use it.

8. ATP Cell’s usable source of energy.
ATP stands for adenosine triphosphate
When ATP is “loaded” with energy, it contains 1 Ribose, Adenine, and Phosphate Groups.
Adenine
Ribose
3 Phosphate groups

9. An adult human converts about
ATP stores a large amount of energy in the bond between the 2nd and 3rd phosphate groups.
Breaking this bond:
Releases ENERGY
Releases a phosphate group
Results in a molecule called Adenosine Diphosphate – ADP.
ATP can be made again by adding a phosphate group to ADP
An adult human converts about
2 billion ATP molecules to ADP + P each minute just to get enough energy to stay alive!

10. AEROBIC CELLULAR RESPIRATION
One way plant and animal cells make ATP
“Aerobic”: with oxygen
2 stages:
Glycolysis: takes place in the cytosol
Oxidative Respiration: takes place in mitochondria
Notice this is the opposite of photosynthesis!
Overall Chemical Equation:
Oxygen + Glucose  Carbon Dioxide + Water + Energy

11. 1. Glycolysis Occurs in the cytosol. Many steps controlled by enzymes.
A glucose (6-Carbon) molecule splits into two 3-Carbon molecules called Pyruvate.
OVERALL GLYCOLYSIS EQUATION
Words
Glucose  2 Pyruvate
Formulas
C6H12O6  2C3H6O3
Energy
2ADP + 2P  2ATP
2 ATP MADE FOR EVERY GLUCOSE IN GLYCOLYSIS
2 Pyruvate enter Mitochondrion

12. 2. Oxidative Respiration
Enzymes on the inner membrane and in the matrix of the mitochondria carry out reactions.
Each pyruvate molecule undergoes a series of complex reactions in the presence of oxygen.
28 ATP MADE FOR EVERY GLUCOSE IN OXIDATIVE PHOSPHORYLATION
OVERALL GLYCOLYSIS EQUATION
Words
2 Pyruvate + 6 Oxygen  6 Carbon Dioxide + 6 Water
Formulas
2C3H6O3 + 6O2  6CO2 + 6H20
Energy
28 ADP + 28 P  28 ATP

13. AEROBIC CELLULAR RESPIRATION SUMMARY (HUMANS)
Exhaled/
Excreted
From Food
Inhaled
Exhaled
CO2
Carbon Dioxide
C6H12O6
Glucose
6O2
Oxygen
6H2O
Water + +
30 ATP
30 ADP +
30 P

14. If glucose is all used up…
FOOD & AEROBIC CELLULAR RESPIRATION
1. Carbohydrates
Enzymes in saliva, stomach, and digestive tract break carbs down into monosaccharides (Glucose, Fructose, Galactose)
If blood glucose is in adequate supply (during a meal), the pancreas releases the hormone insulin which causes glycogen to be formed in the liver for glucose storage.
Between meals, the pancreas releases the hormone glucagon which causes glycogen in the liver to be converted back to glucose.
Glucose enters cellular respiration in glycolysis as normal
Fructose and Galactose undergo modified versions of glycolysis to make pyruvate and enter oxidative respiration
If glucose is all used up…
Molecule
How it results in ATP production
Carbohydrate
Enzymes in saliva, stomach, and digestive tract break carbs down into monosaccharides
If glucose is in adequate supply (during a meal), insulin causes glycogen to be formed in the liver for glucose storage.
Between meals, glycogen is converted back to glucose.
Glucose undergoes glycolysis as normal
Other monosaccharides undergo modified versions of glycolysis to make pyruvate
If all glucose supplies are depleted, other substances in the body are converted to glucose or intermediate products of respiration.
Fats
Used if glucose sources are depleted
Stored in adipose tissue
When needed, fats broken down into glycerol and fatty acids
Glycerol is modified to one of the intermediate products of glycolysis and respiration can happen
Proteins
Only used if glucose and fat sources are depleted

15. If glucose & fat storage is all used up…
FOOD & AEROBIC CELLULAR RESPIRATION
2. Fats
Used if glucose sources are depleted
Stored in adipose tissue
When needed, fats are broken down into glycerol and fatty acids
Glycerol is modified to one of the intermediate products of glycolysis and respiration can happen
If glucose & fat storage is all used up…
Molecule
How it results in ATP production
Carbohydrate
Enzymes in saliva, stomach, and digestive tract break carbs down into monosaccharides
If glucose is in adequate supply (during a meal), insulin causes glycogen to be formed in the liver for glucose storage.
Between meals, glycogen is converted back to glucose.
Glucose undergoes glycolysis as normal
Other monosaccharides undergo modified versions of glycolysis to make pyruvate
If all glucose supplies are depleted, other substances in the body are converted to glucose or intermediate products of respiration.
Fats
Used if glucose sources are depleted
Stored in adipose tissue
When needed, fats broken down into glycerol and fatty acids
Glycerol is modified to one of the intermediate products of glycolysis and respiration can happen
Proteins
Only used if glucose and fat sources are depleted

16. FOOD & AEROBIC CELLULAR RESPIRATION
3. Proteins
Used if glucose and fat storage are depleted
Proteins broken down into amino acids
Most AAs are used to build new proteins (healthy)
AAs can be converted into pyruvate or other intermediate cellular respiration molecules – a process which creates the harmful byproduct, urea (excreted in urine).

17. Your body needs food! Pay attention:
Before watching this video, please note:
This is purely for educational purposes
Do not focus on the religious aspects
Do NOT attempt what she did – many of her organs (liver, kidneys, stomach, brain, etc…) are probably damaged beyond repair.
Pay attention:
she is NOT CONSUMING ANYTHING except for water.
Her carbohydrate storage is being used up
Her fat storage is being used up
Her proteins (last resource) are being used for energy
Her physical and mental health are suffering
Remember – brain tissue NEEDS ENERGY to function properly.