Chapter 4 Cell Energy:

Photosynthesis & RespirationPlants go through

photosynthesis our body does the _________- continuous cycle

Experiments Jan Van ______- planted tree- 5 yrs later- no soil mass change- tree grew source was WATER not soil

Joseph ______- candle and plant in glass bell- candle alone did not burnplant w/______- plant produced O2 needed for candle to burn

Requirements for

Photosynthesis

air- CO2

________H2O

Products of Photosynthesis- glucose (simple sugars)

- ________

Photosynthesis & NRG – some terms

________use a source of direct nrg (sunlight) to produce food from _______ molecules

heterotrophCannot produce own source of food

obtain nrg from foods eaten- other ________ and autotrophs

Structure of Chloroplast

thylakoid membrane

________

_______

light reactions- ________ membranes

________ reactions- stroma

electron micrograph of plant chloroplast

Light Reactions pigments capture sunlight to

“make” nrgchlorophyll absorbs red-orange-blue-violet-but __________ green

happens in the disk structures called thylakoid membranes

can be summarized in 4 actions…

Light Reactions 1- light is absorbed by

pigments- light is passed from pigment to pigment

2- electron transport- high nrg e- passed along by carriers- converts _______ to NADPH (E storing compound)

3- ________ production4- ATP formation- ADP+P by

enzyme in thylakoid membranes

Calvin Cycle (_____ __________ )“dark” because light does not

play a specific role in these reactions- could happen in light OR dark

uses: ATP and high E __________ (e- raised to a higher nrg level by absorption of sunlight)

happens in the ________ of chloroplast

Calvin Cycle (Dark Reactions )5-C sugar combines w/CO2 to

make 2 3-C sugars (enzyme rubisco helps)

the 3-C sugars are converted to PGAL w/nrg in NADPH & ATP (light rxns)(phosphoglyceraldehyde) makes glucose

Calvin cycle must go around ______ to produce 1 molecule of glucose- why??hint- glucose is a 6-C sugar

brief pictorial representation of photosynthesis

The two reactions together

(light and dark)- make the

GLUCOSE for plants

The opposite reaction (process)…Respiration

Where does nrg come from for animals?Respiration- 2 types

aerobic respiration- oxygen required

anaerobic respiration- no oxygen required

Anaerobic = fermentation

Glucose 2 ethanol + 2 carbon dioxide + 2

ATPsonly 2 ATPs (compare that later

to # produced by Aerobic)C6H12O62 CH3CH2OH + 2 CO2 +

NRG (ethanol)

(2 ATP)

2 types of Fermentation

Alcoholic Fermentation

Lactic Acid Fermentation

Alcoholic Fermentation takes place in yeast cells & a few

other microorganisms- important to bakers and brewers…Why?

glucose broken down into:2-Carbon alcoholCO2

produces “bubbles” in beer, sparkling wine

allows bread to rise

Lactic Acid Fermentation

happens in muscle cellshard workouts- no O2 – NRG still needs to be produced- cell changes to anaerobic respiration

build-up of lactic acid causes a burning, painful sensation in muscles

Aerobic RespirationC6H12O6 +6O26 CO2 + 6 H2O + E (38

ATP)

glycolysis and respirationglycolysis- glucose is broken down into pyruvic acid (cytosol)

pyruvic acid moves into mitochondria for Kreb’s cycle (citric acid cycle)38 ATP produced (net)!

Aerobic Respiration

Electron Transport Chain

This takes place in the inter membrane of the Mitochondrion

This is where most of the ATP is made.

A pair of electrons moving down the chain can

Produce enough energy to make 3 ATP