Chapter 6 Cell Energy: Photosynthesis & Respiration Plants 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 burn plant 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 heterotroph Cannot 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” nrg chlorophyll 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- ________ production 4- 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 ATPs only 2 ATPs (compare that later to # produced by Aerobic) C6H12O62 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 alcohol CO2 produces “bubbles” in beer, sparkling wine allows bread to rise

Lactic Acid Fermentation happens in muscle cells hard 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 Respiration glycolysis and respiration C6H12O6 +6O26 CO2 + 6 H2O + E (38 ATP) glycolysis and respiration glycolysis- 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