Ch 9: Energy in a Cell ATP, Photosynthesis and ATP, Photosynthesis and

Cellular RespirationCellular Respiration

I. EnergyA. Energy is essential for life. All

living organisms must be able to obtain energy from the environment they live in.

B. Plants are able to trap the light energy in sunlight and store it to use when necessary. (Autotrophs)

C. Animals obtain energy from plants or other animals that eat plants. (Heterotrophs)

D. Energy is stored in chemical bonds of ATP = adenosine triphosphate.

ATP made of:made of:

1. 1. adenosine moleculeadenosine molecule2. 2. ribose sugarribose sugar3. 3. three phosphatesthree phosphates

held together by chemical bondsheld together by chemical bonds

ATP Cycle When a phosphate is broken off of ATP, When a phosphate is broken off of ATP,

energy is energy is releasedreleased and ADP is formed. and ADP is formed. When a phosphate is added to ADP, When a phosphate is added to ADP,

energy is energy is storedstored and ATP is formed. and ATP is formed.

**So the way energy is stored and **So the way energy is stored and released with ATP is released with ATP is to add or remove a to add or remove a phosphatephosphate..

Formation and breakdown of ATP creates a source of energy

adenosine

adenosine PP P

P

P P

P

Adenosine triphosphate (ATP)

Adenosine diphosphate (ADP)

energy

energy

III. ATP EquationIII. ATP Equation

This formula is a true reversible This formula is a true reversible reaction and is shown with a double-reaction and is shown with a double-headed arrow. The molecules can be headed arrow. The molecules can be used over and over again. It can be used over and over again. It can be written with ATP on the left or on the written with ATP on the left or on the right.right.ADP + P + energy ATPADP + P + energy ATP

ORORATP ADP + P + energyATP ADP + P + energy

Uses of Cell Energy A. Provide energy for muscle cells

(muscle contraction)

B. Cell division and cell repair

C. Maintain homeostasis

D. Transport molecules and proteins through the cell membrane.

E. Making molecules

Photosynthesis

VocabularyA.A. PhotosynthesisPhotosynthesis – process by – process by

which autotrophs turn sunlight which autotrophs turn sunlight into chemical energy; make into chemical energy; make foodfood

B.B. PigmentsPigments – compounds that – compounds that absorb/reflect wavelengths of absorb/reflect wavelengths of light light

Vocabulary

C.C. ChlorophyllChlorophyll – green pigment – green pigment found in plant chloroplastsfound in plant chloroplasts

D.D. ChloroplastChloroplast – cell organelle – cell organelle where photosynthesis occurswhere photosynthesis occurs

What is the ultimate source of all energy?

How does the energy get from the sun into the foods we eat?

energy

energy

What process captures the light energy and uses it to make food?

OVERVIEW OF PHOTOSYNTHESIS

PLANTS TAKE INCO2 AND H2O

PLANTS MAKE GLUCOSE AND OXYGEN

SUNLIGHT PROVIDES THE ENERGY

FOR PHOTOSYNTHESIS

Photosynthesis What is photosynthesis?What is photosynthesis? Photosynthesis is the process Photosynthesis is the process

by which:by which:

water

carbon dioxide

oxygen

glucose

TAKE IN AND USING MAKE

PLANTS(producers)

light

chlorophyll

Photosynthesis Formula How would this be written as a

chemical equation? What goes in? (the reactants) What comes out? (the products)

H2O Light Reaction Dark ReactionC

O 2C6H12O6

O 2

chlorophyll

H2O CO2 C6H12O6 O2

Photosynthesis Formula What’s wrong with this equation? The number of atoms is not equal on

both sides of the equation.

Balance the equation so that the number of atoms of each element is equal on both sides.

H2O CO2 C6H12O6 O2

one carbon atom reactant

6 carbon atoms product

6 6 6(1)

Now balance it as if TWO glucose molecules were being produced.

Photosynthesis Review What goes in? (the reactants) What comes out? (the products)

H2O Light Reaction Dark Reaction

CO 2

C6H12O6

O 2

chlorophyll

6CO2 + 6H2O 6O2 + C6H12O6

light

chlorophyll

How do cells make energy?

Cellular RespirationCellular Respiration

I. Cellular Respiration Cellular Respiration – the process by which glucose molecules are broken down to release energy

• Series of chemical reactions which produce ATP.

• There are 2 forms of cellular respiration.

• Mitochondria is the cell organelle where respiration occurs.

A. 2 Forms of Cellular Respiration:

1. Aerobic Respiration – requires oxygen & produces 36 ATP molecules

2. Anaerobic Respiration – does NOT require oxygen & produces 2 ATP molecules

Cellular Respiration What is cellular respiration?What is cellular respiration? Cellular respiration is the process Cellular respiration is the process

by which:by which:

water

carbon dioxide

oxygen

glucose

TAKE IN MAKE

mitochondria

ATP

Cellular Respiration FormulaHow would this be written as a chemical

equation?What goes in? (the reactants) What comes out? (the products)

H2O CO2C6H12O6O2

Equation for Cellular Respiration

C6H12O6 + 6 O2 6 CO2 + 6 H2O + ATP

mitochondriamitochondria

animal cellsanimal cells plant cellsplant cells

PhotosynthesisPhotosynthesis Cellular RespirationCellular Respiration

food synthesizedfood synthesized food broken down food broken down

energy from sun stored in energy from sun stored in glucoseglucose

energy of glucose released energy of glucose released

carbon dioxide taken incarbon dioxide taken in carbon dioxide given off carbon dioxide given off

oxygen given offoxygen given off oxygen taken in oxygen taken in

produces sugars produces sugars produces carbon dioxide and produces carbon dioxide and water water

requires lightrequires light does not require light does not require light

occurs only in presence of occurs only in presence of chlorophyllchlorophyll

occurs in all living cells occurs in all living cells