Cell Energy

ATP, Photosynthesis, and Respiration

The Energy Molecule- ATP Energy in the body is used to

maintain homeostasis Homeostasis- maintaining a

constant internal environment even though external conditions change

Examples of Homeostasis Body temperature regulation

                                                                                                       

     

When it is cold we shiver

When it is hot we sweat

Examples of Homeostasis Glucose

regulation in the blood

The Energy Molecule- ATP ATP is the molecule in the body

that stores energy in the bonds between phosphate groups. When a bond between the phosphate groups is broken, energy is released.

The Energy Molecule- ATP Parts of an ATP molecule

ATP stands for the molecule adenosine triphosphate.

ATP contains one base, one sugar, and 3 phosphate groups

Sugar- ribose

Base-adenine

P P P

The Energy Molecule-ATP ADP- Adenosine Diphosphate- 2

phosphate groups

AMP – Adenosine Monophosphate – 1 phosphate group

Sugar- ribose

Base-adenine

P P

Sugar- ribose

Base-adenine

P

The Energy Molecule-ATP Cycling of ATP

ATP gains a phosphate through cellular respiration-stores energy

ATP loses a phosphate-energy is released

The Energy Molecule-ATP

Photosynthesis Producers like plants, algae and

some bacteria

Plants trap energy from the sun, and build glucose molecules

Light energy is converted to chemical energy.

Photosynthesis Pigments Light is absorbed by pigments in

the chloroplasts called chlorophyll. Chlorophyll is a green pigment that absorbs most wavelengths of light.

Other pigments include the colors red, orange, and yellow.

chloroplast

Photosynthesis Overall reaction for photosynthesis 6 CO2 + 6 H2O C6H12O6 + 6O2

Energy, light,

& chlorophyll

Photo synthesis 2 phases of photosynthesis

The light-dependent reaction The light-independent reaction (dark reaction)

Photosynthesis Light-dependent reaction Light is converted to ATP, a form of

chemical energy The electron transport chain is

when electrons from light are passed from one protein to another. Small amounts of energy are released along the way that convert ADP to ATP.

PhotosynthesisLight-Dependent Reaction

ATP & H+

H2O

sunlight

Electron Transport Chain Products go to

Light-Independent Reaction

Photosynthesis Light-independent reaction (dark

reaction) ATP is converted to glucose The Calvin Cycle is a series of

reactions that use CO2 to form carbohydrates, mainly glucose.

PhotosynthesisLight-Independent Reaction

ATP & H+

Calvin Cycle

CO2

Glucose

Summary of Photosynthesis

Light & enzymes

H2

OO2

Glucose

H2

O

ATP & H+

CO2

Light Reaction

DarkReaction

Cellular Respiration Cellular Respiration Process of breaking down food

molecules to produce energy (ATP)

Cellular Respiration Types of respiration

Aerobic respiration requires oxygen

Anaerobic respiration uses no oxygen

Cellular Respiration 3 stages of aerobic respiration

Glycolysis Citric acid cycle Electron transport chain

Cellular Respiration 1. Glycolysis- Glucose, a six carbon

sugar, is broken down into 2 molecules of pyruvic acid, a 3 carbon molecule. 2 ATP used, 4 ATP made or gained,

therefore there is a net gain of 2 ATP. This reaction does not use oxygen and is

therefore an anaerobic process. This reaction occurs in the cytoplasm

Cellular Respiration Pyruvic acid now moves to the

mitochondria where aerobic respiration can take place.

2. Citric Acid Cycle (Kreb’s cycle) Pyruvic Acid is broken down to

release CO2 and 2 ATP.

Cellular Respiration Electron Transport Chain

Oxygen is used to make water and 32 ATP.

Cellular Respiration Overall Reaction for Aerobic Respiration

C6H12O6 + 6O2 6 CO2 + 6 H2O

NOTE: Photosynthesis is the opposite

reaction of respiration. The reactants of one are the products of the other.

Cellular Respiration

Cellular Respiration Anaerobic Respiration – 2 types

Lactic Acid Fermentation

Alcoholic Fermentation

Cellular Respiration Lactic Acid Fermentation- occurs

when oxygen is scarce.

Pyruvic acid is converted into 2 molecules of lactic acid and 2 molecules of ATP.

Lactic Acid causes muscle fatigue in the body.

Cellular Respiration Alcoholic fermentation- organisms like

yeast and bacteria use this process to produce energy without the use of oxygen

Pyruvic acid is converted to ethyl alcohol, carbon dioxide and 2 ATP

When yeast is used to make bread, the carbon dioxide causes bubbles to form in the dough.

Cellular Respiration Summary

Glucose

Glycolysis Pyruvic acid 2

ATP

Anaerobic Aerobic

Lactic Acid Fermentatio

n

Alcoholic Fermentatio

n

Lactic Acid 2 ATP

Ethyl Alcohol, CO2, 2 ATP

In cytoplas

m

In mitochondri

on

Electron Transport Chain 32 ATP

Kreb’s Cycle 2 ATP

36 ATP, CO2 & H2O

Summary of RespirationCharacteristic Starting

materials1st step Uses

oxygenCell location Products Number of

ATP produced

Net Gain of ATP

Aerobic

Respiration

Glucose Glycolysis Yes Mitochondria CO2, H2O, energy (ATP)

38 ATP 36 ATP

Lactic Acid Fermentation

Glucose Glycolysis No Cytoplasm Lactic acid, ATP

4 ATP 2 ATP

Alcoholic Fermentation

glucose Glycolysis No cytoplasm Ethyl alcohol, CO2, ATP

4 ATP 2 ATP

Comparison of Photosynthesis and Respiration

Characteristics Photosynthesis Aerobic Respiration

Reactants/requirements

CO2, H20, light,

chlorophyll, enzymes

Glucose, O2

Products Glucose, O2CO2, H20, 36 ATP

Location chloroplasts mitochondria

Use of energy storage release

Use of food molecules Food made Food broken down