Unit V: Energy in a Cell

Energy the ability to do work; how it is made and how it is used.

A. Energy

1. Energy is the ______________________.

Forms of energy: _______, _________, ______

______________

________________(movement)

1st Rule of Thermodynamics:Energy can not be _______ nor ________Energy just changes ________

Chemical Mechanical Heat

2. Energy in the Body - Use energy for _______________, __________, _________, __________, _______________, etc. - ex: nerves, muscles, kidneys, enzymes, ribosomes

-Comes from the food we eat -body breaks down nutrients so they can becarried and enter our cellsto be turned into useable energy

3. ATP = ______________________________

- __________________ Molecule

- ATP is the cell’s ____________ form of energy

- Cells need ______________________ supply

Easier Version

________________(nitrogenous base)

________ (sugar)

__________________

High Energy Bond

4. ADP + P

- __________________ + Phosphate

- Made of the same parts as ATP but not completely assembled

- Missing the ____________________

- ADP is a low energy molecule

Missing high energy bond

5. ATP ADP Cycle

- instead of constantly making new molecules the cells save energy by ______________ ATP & ADP

When the high energy bond in ATP is broken ________________ for cellular activities

Energy from glucose in the process of ______________ turns low energy ADP into high energy ATP by creating the high energy bond

- ATP briefly stores energy

Storing energy = potential energy

Energy is stored in the _______________.

- Energy to make ATP comes from _________.

- Glucose molecules store energy in the ________.

- What do cells use and store energy for?

high energy bond

glucose

bonds

Active Transport Phagocytosis

Cyclosis Muscle Contractions

Nerve Impulses Synthesis

B. PhotosynthesisAs a plant grows, from tiny seedlings into massive

trees, from what do they gain their mass?

1. Early Experiments with Photosynthesisa. Van Helmont’s Experiment

- 1600s Belgian Physician- Planted the seedling, watered it regularly, and observed its growth- Measured mass of dry potting soil and small

seedling- At the end of 5 years the plant gained 75kg- When he measured the soil – it was the same mass at the beginning of the experiment

What is his conclusion? ? ???

??

???

?? ?

b. Joseph Priestly - 1772Candle burns out when placed under a jarContinues to burn when sprig of mint is placed with it

Conclusion?

c. Jan Ingenhousz - 1779 Repeated the Priestly experiment but blocked out the light. Candle only burned when the plant was exposed to light.

Conclusion?

2. Light- The light from the sun = white lightWhite light = all the colors combined- Light is Energy

- Colors of LightR O Y G B I V

- Plants absorb energy from light by using ________________

____________________________________

- Transfers energy to _______________ high energy electrons makephotosynthesis work

- Store energy of light in ______________

3. The Photosynthesis Equation

6 molecules of carbon dioxide react with 6 molecules of water to form 1 molecule of glucose and 6 molecules of oxygen.

+ +

Photosynthesis uses the energy of sun light to convert carbon dioxide and water into high energy sugars and oxygen gas.

• 4. The Chloroplast

- __________ = sac-like membranes, contain chlorophyll, other pigments, and photosystems- _______ = fluid inside the chloroplast

5. Light Dependant Reactions = Photolysis- requires light and produces ATP, NADPH, O2

1) ____________ by photosystem2) ______ electrons (more energy)3) Excited electrons picked up by ______________________4) Electrons give off energy and produce _____; to replace excited electrons – enzymes split ______ and produce ________ gas5) Low energy electrons and light reaches next photosystem6) Light re-excites electrons – gives more _____________ 7) Electrons move along _______ 8) High energy electrons produce __________

Simplified Chlorophyll catches light and gives the energy to electrons.

Electrons use the energy to make ATP and NADPH

ATP and NADPH are energy carrying molecules

Plants use H2O and light to make useable forms of energy and oxygen

6. Light Independent Reactionsalso known as the Dark Reactions or Calvin Cycle

- Uses _____ and ________ to produce high energy ________. 1) ______________ molecules enter the stroma 2) Enzyme _________ carbon atoms together – use the energy from ATP and NADPH 3) Carbons combine and form 6 carbon high energy sugar molecules (Glucose)

ATP and NADPH generated in light reactions used to fuel the reactions which take CO2 and break it apart, then reassemble the carbons into glucose.Called __________: taking carbon from an inorganic molecule (atmospheric CO2) and making an organic molecule out of it (glucose)Simplified version of how carbon and energy enter the food chain

7. Factor Affecting Photosynthesisa. Amount of _______b. _____________c. Available ________d. Light _________

8. _______________Can life survive without _________?2 CO2 + 4 H2 2 CH4 + 2 O2

Production of MethaneBacteria can change methane intosimple sugars that other organismscan use

9. The Leaf

- Specialized ___________ designed to carry out photosynthesis

- Relatively ____________________

- Thin and flat – allow _________ to pass through

Stomata

- Cuticle – waxy coating to help prevent water loss- Epidermis – single layer of thin cells, produce cuticle- _______________ – site of the majority of photosynthesis- Spongy layer – allows for gas exchange- ________________________ •Holes that allow for the exchange of gasses and water vapor •When guard cells have water – swell and open stomata •When guard cells don’t have water – shrink and close stomata

___________ – process by which plants use evaporation from the leaves to draw water up the plant from the roots. Lose a lot of H2O

C. Cellular Respiration

- _________________________ in food (glucose) into ATP

- Done by ____________ organism

- Food molecules need to be converted

to energy, but not all at once.

- The food needs to be broken down ________ to yield usable amounts.

1. ___________________ 1st step in cellular respiration for both anaerobic and aerobic respiration

a. releases a _______ amount of energy

b. one molecule of glucose is broken in ________, producing two molecules of PGAL (3-carbon compound 3 is half of 6) PGAL is often converted into Pyruvic Acid (3 carbon compound slightly different from PGAL)

c. __________________ – 2 ATP molecules are used to start the reaction. They add energy to break apart the glucose.

d. Energy Production2 ATP 4 ATP net gain of 2 ATP 2 were required to start the reaction 4 -2 = 22 NAD+ 2 NADH - holds high energy electrons for use in the electron transport chain

sounds similar to photosynthesis

2. _____________________ also known as ____________________

- ______________ present = anaerobic- Anaerobic Respiration / Fermentation is the same as Glycolysis with a little extra step- Extra Step:

NADH passes its high energy electron back to pyruvic acidNADH NAD+ cycle that allows glycolysis and ATP production to continue

a. Alcoholic Fermentation - performed by _________and some other microorganisms when O2 not available - produces carbon dioxide and ethyl alcohol Glucose + 2 ATP alcohol + CO2 + 4 ATP

b. Lactic Acid Fermentation - performed by certain _______ and ______________ cells when O2 not available or used up too quickly - Glucose + 2 ATP lactic acid + 4 ATP - build up of lactic acid in cells cause fatigue and painful, burning sensations

3. ______________ Cellular Respiration- ____________ break down of glucose

C6H12O6 CO2

- Requires ________________- 2 Step Process (Krebs Cycle and ETC)- Glycolysis is still the first step to produce pyruvic acid- Make a net gain of molecules from 1 glucose molecule

in anaerobic respiration there was only a net gain of

- Aerobic makes much _________ usable energy- At the end Oxygen acts as electron acceptors

a. The Krebs Cycle- also known as the citric acid cycle- begins when pyruvic acid from glycolysis enters the _____________- pyruvic acid loses CO2 and is acted on by Coenzyme A to become a two carbon compound called Acetyl-CoA- Acetyl-CoA becomes Citric Acid- As citric acid is broken down CO2 is released, high energy electrons are formed, and 1 molecule of ATP is formed- High Energy Electron Carriers

NAD+ NADHFAD FADH2

- NADH and FADH2 Bring electrons to Electron Transport Chain to make more ATP

Makes a high energy electrons to use in the electron transport chain, a small amount of ATP, and Some CO2

b. Electron Transport Chain- located in the ____________ _________ of the ____________

- Use high ____________ from NADH and FADH2 to synthesize ATP

-H+ ions are carried across the membrane – makes a ________-_______________

- H+ ions escape through _________________ making ATP (same way as photosynthesis)

- H+ ions combine with O2 to form __________- Oxygen acts as the final electron acceptor

c. Overall View of Aerobic Cellular Respiration

Cellular Respiration Animation

• Energy and Exercise

Sprints = lactic acid build up (pay for it later)

Endurance = use glycogen – pace yourself

• Compare aerobic cellular respiration and photosynthesis

Aerobic Respiration Photosynthesis

Function

Location

Reactants

Products

Formula