Energy in a Cell Energy in a Cell ATP: Energy in a Molecule ATP: Energy in a Molecule Photosynthesis: Trapping Energy Photosynthesis: Trapping Energy Cellular

Energy in a CellEnergy in a Cell

ATP: Energy in a MoleculeATP: Energy in a Molecule Photosynthesis: Trapping EnergyPhotosynthesis: Trapping Energy Cellular Respiration: Getting Cellular Respiration: Getting

Energy to Make ATPEnergy to Make ATP

ATP: Energy in a MoleculeATP: Energy in a Molecule

Cell energyCell energy Organisms and their cells need an endless supply Organisms and their cells need an endless supply

of energy in order to functionof energy in order to function Energy to walk, talk, bend, exerciseEnergy to walk, talk, bend, exercise Cells get energy from the food you eatCells get energy from the food you eat

Organisms break down food into small nutrient Organisms break down food into small nutrient molecules that can enter your bloodstreammolecules that can enter your bloodstream

Cells then break down the food moleculesCells then break down the food molecules Cells use some of the ATP from the food molecules, Cells use some of the ATP from the food molecules,

then store the restthen store the rest


ATPATP ATP is known as the cell’s “money”ATP is known as the cell’s “money” Cells must have plenty of ATP “money” to spend Cells must have plenty of ATP “money” to spend

whenever the cell needs to workwhenever the cell needs to work Without a constant supply of ATP, the cell will dieWithout a constant supply of ATP, the cell will die Cells use to ATP for many thingsCells use to ATP for many things

make ribosomesmake ribosomes help with cell divisionhelp with cell division for active transportfor active transport Maintain Maintain homeostasishomeostasis

The ATP moleculeThe ATP molecule


Forming and breaking down ATPForming and breaking down ATP Cells store energy by adding a phosphate group to Cells store energy by adding a phosphate group to

a ADPa ADP ADP + P ADP + P ATP (energy) ATP (energy) Adenosine Adenosine didiphosphate phosphate adenosine adenosine tritriphosphate phosphate

When cells use energy, the process works in When cells use energy, the process works in reversereverse

ATP ATP ADP + P (energy is released) ADP + P (energy is released) The process is then ready to start all over againThe process is then ready to start all over again

Redox ReactionsRedox Reactions

Most of the important energy changes in Most of the important energy changes in organisms involve chemical reactions known organisms involve chemical reactions known as oxidation reduction reactions. as oxidation reduction reactions.

Photosynthesis & cellular respiration are Photosynthesis & cellular respiration are oxidation reduction reactions.oxidation reduction reactions.

OxidationOxidation

Involves the :Involves the :

Releases EnergyReleases Energy Combining with OxygenCombining with Oxygen Loss of ElectronsLoss of Electrons Loss of HydrogenLoss of Hydrogen

ReductionReduction

Involves the:Involves the:

Absorption of EnergyAbsorption of Energy Separation from OxygenSeparation from Oxygen Gain of ElectronsGain of Electrons Gain of HydrogenGain of Hydrogen

LEO the Lion goes GERLEO the Lion goes GER

Loss of Electrons is OxidationLoss of Electrons is Oxidation

Gain of Electrons is ReductionGain of Electrons is Reduction

Photosynthesis: Trapping EnergyPhotosynthesis: Trapping Energy

Autotrophs/the producers of the planetAutotrophs/the producers of the planet Autotrophs are organisms that can make their own Autotrophs are organisms that can make their own

food (plants)food (plants) Autotrophs make their own food through the Autotrophs make their own food through the

process of photosynthesisprocess of photosynthesis They make simple sugars that other organisms can They make simple sugars that other organisms can

break down into ATPbreak down into ATP Autotrophs trap energy from sunlight and use the Autotrophs trap energy from sunlight and use the

energy to build carbohydrates (sugars)energy to build carbohydrates (sugars)


The green pigment chlorophyll absorbs The green pigment chlorophyll absorbs sunlightsunlight Found in the chloroplastsFound in the chloroplasts Plants also have other colored pigments that help Plants also have other colored pigments that help

trap sunlighttrap sunlight These pigments give plants their bright colorsThese pigments give plants their bright colors

ChlorophyllChlorophyll

PhotosynthesisPhotosynthesis

The process by which plants use light energy The process by which plants use light energy to make food molecules from CO2 & H2Oto make food molecules from CO2 & H2O

Larry the SunLarry the Sun

Light

H+

O2-

H2O ATP

Light Reaction

chlorophyll zapped within chloroplast

Calvin the MoonCalvin the Moon

CO2

ATP (from light reaction) (Dark Reaction)

Calvin Cycle

glucose or

C6H12O6 or

sugarH+


Photosynthesis: the basic stepsPhotosynthesis: the basic steps 11stst step – chloroplasts trap sunlight step – chloroplasts trap sunlight 22ndnd step – light energy is converted to chemical step – light energy is converted to chemical

energy (sugar) and then storedenergy (sugar) and then stored Water and carbon dioxide are also required for this stepWater and carbon dioxide are also required for this step

The general equation for photosynthesis is:The general equation for photosynthesis is: 6CO6CO22 + 6H + 6H22O + light energy O + light energy C C66HH1212OO66 + 6O + 6O22

carbon dioxide plus water plus light produces sugar and carbon dioxide plus water plus light produces sugar and oxygen (in the presence of chlorophyll)oxygen (in the presence of chlorophyll)


PhotosynthesisPhotosynthesis There are 2 main groups of reactions that take There are 2 main groups of reactions that take

place during photosynthesisplace during photosynthesis Light reactionsLight reactions Calvin cycle (formerly called the dark reaction)Calvin cycle (formerly called the dark reaction)

Light reactions occur when light energy is Light reactions occur when light energy is converted to chemical energyconverted to chemical energy

This is the This is the photophoto part of photosynthesis part of photosynthesis These reactions split water molecules and provide the These reactions split water molecules and provide the

energy for the Calvin cycleenergy for the Calvin cycle


PhotosynthesisPhotosynthesis The Calvin cycleThe Calvin cycle

The series of reactions that form simple sugars using The series of reactions that form simple sugars using carbon dioxide and hydrogen (from water)carbon dioxide and hydrogen (from water)

The Calvin cycle is the The Calvin cycle is the synthesissynthesis part of photosynthesis part of photosynthesis


The Light ReactionsThe Light Reactions1)1) Light strikes chlorophyll Light strikes chlorophyll 2)2) Electrons gain energy and jump out of Electrons gain energy and jump out of

chlorophyllchlorophyll3)3) The electrons move down the The electrons move down the electron transport electron transport

chainchain4)4) The electrons give off energy, which is used to The electrons give off energy, which is used to

make ATPmake ATP5)5) Electrons from water move to the chlorophyll, to Electrons from water move to the chlorophyll, to

replace the lost electronsreplace the lost electrons


The Light ReactionsThe Light Reactions6)6) Water breaks up into hydrogen and oxygenWater breaks up into hydrogen and oxygen

7)7) Light causes the electrons to gain energy and Light causes the electrons to gain energy and leave the chlorophyll againleave the chlorophyll again

8)8) Electrons and hydrogen are added to NADPElectrons and hydrogen are added to NADP++, , which produces NADPH + Hwhich produces NADPH + H++

9)9) The ATP made in the light reactions will be used The ATP made in the light reactions will be used in the 2in the 2ndnd stage of photosynthesis – the Calvin stage of photosynthesis – the Calvin cyclecycle

Electron transport chainElectron transport chain


The Calvin CycleThe Calvin Cycle1.1. This is a complex chemical reaction that uses This is a complex chemical reaction that uses

ATP to make simple sugarsATP to make simple sugars1.1. A 5 carbon sugar is formedA 5 carbon sugar is formed

2.2. It breaks into two 3 carbon sugarsIt breaks into two 3 carbon sugars

3.3. The two 3 carbon sugars go through some chemical The two 3 carbon sugars go through some chemical reactions and finally make a 5 carbon sugarreactions and finally make a 5 carbon sugar

4.4. The process starts again when a carbon from COThe process starts again when a carbon from CO22 is is

used to turn the 5 carbon sugar into a 6 carbon sugarused to turn the 5 carbon sugar into a 6 carbon sugar This is called carbon fixationThis is called carbon fixation

The Calvin CycleThe Calvin Cycle

Photosynthesis: Trapping Photosynthesis: Trapping Energy/LocationsEnergy/Locations

Overview :Light reaction and Calvin cycleOverview :Light reaction and Calvin cycle Light reactions take place in the thylakoidsLight reactions take place in the thylakoids The Calvin cycle takes place in the stromaThe Calvin cycle takes place in the stroma The light reactions make the ATP that is used to The light reactions make the ATP that is used to

make sugar (food) during the Calvin cyclemake sugar (food) during the Calvin cycle Animals then eat the sugars to get energy they need to Animals then eat the sugars to get energy they need to

survive & thrivesurvive & thrive

Now….Add the Now….Add the PhotosystemsPhotosystems

a)a) (PSII) Light is absorbed by ?? or other pigments in (PSII) Light is absorbed by ?? or other pigments in photosystem II. This E from ?? is then transferred to electrons photosystem II. This E from ?? is then transferred to electrons which are then passed down the ??. Separately enzymes break which are then passed down the ??. Separately enzymes break apart ?? Into electrons & of ?? Ions & ??.apart ?? Into electrons & of ?? Ions & ??.

a)a) (ETC) Electrons from ?? move though the ETC to (ETC) Electrons from ?? move though the ETC to photosystem I. E from this process are used to transport ?? photosystem I. E from this process are used to transport ?? ions from the stroma into the inner ??.ions from the stroma into the inner ??.

a)a) (PSI) As in PSI, pigments add E from light to the electrons. (PSI) As in PSI, pigments add E from light to the electrons. The high E electrons are then picked up by NADP+ to The high E electrons are then picked up by NADP+ to form ??.form ??.

And then…And then…

d) (H ion movement) The inside of the ?? fills with H + ions, d) (H ion movement) The inside of the ?? fills with H + ions, giving the membrane an overall charge. The difference in giving the membrane an overall charge. The difference in charges provides the E to make ATP.charges provides the E to make ATP.

e) (ATP formation) A protein called ??? allows the H ions to pass e) (ATP formation) A protein called ??? allows the H ions to pass through & it rotates (like a turbine with water running over it through & it rotates (like a turbine with water running over it at a hydroelectric power plant). As this happens the protein at a hydroelectric power plant). As this happens the protein binds ADP & PO4 to produce ???.binds ADP & PO4 to produce ???.


Life without lightLife without light Some organisms are able to energy without Some organisms are able to energy without

sunlightsunlight Mainly bacteriaMainly bacteria They are They are chemosyntheticchemosynthetic – they are autotrophs that can – they are autotrophs that can

use different chemicals to produce methaneuse different chemicals to produce methane These types of bacteria live near deep cracks in the These types of bacteria live near deep cracks in the

ocean floorocean floor

Chemosynthetic vent wormsChemosynthetic vent worms

Documents

Energy in a Cell Energy in a Cell ATP: Energy in a Molecule ATP: Energy in a Molecule Photosynthesis: Trapping Energy Photosynthesis: Trapping Energy Cellular