Food and energy

Food and energy

Food and energyPhotosynthesis&

Resipiration Probably two most complex biological processes we do.

Deprived a living org of matter or energy or both and we eventually die

w/o photosynth everything dies. Single most important process in the world.

What is phtotsynthGreen stuff converts inorganic to organic. Its pretty much that simple.

Then that matter gets passed through the food chains to other orgsCellular respOccurs in both plants and animal cells. Breaking down organic compounds into smaller units with energy trapped in chemical bonds being released for use by cells or body tissuesEnergy storage and use - ATPIf ALL the energy in a sugar molecule was released it would generally be too much for most cell actions.

therefore, cells require smaller packets of energy to use effectively.

Cells use adenosine triphosphate (ATP) to store and then use for energyDecomp reaction breaks ATP down into ADP + P+ ENERGY(what does that D stand for?)

ATP ADP + P + Energy

photosynthAll processes involving sythesis or breakdown of matter fall under the heading metabolism

Anabolism write that down is the creation of organic matterCanabolism same thing is the breaking down of organic matter to release stored energyDont eat for 10+ hours? Your body begins to canabolize muscle tissue. Think starving yourself is a good way to get toned think again, your body will store foods as FAT and canabolize muscle tissue because it thinks youre going to starve it again. And fat contains more calories, so it would be better to have stored fat in a starved situation than lots of muscle.The innitial organic items then become the building blocks/ sources of energy for other living tissue. Not just plants, but EVERYTHING

Green plants, make their own energy- autotrophsOther orgs heterotrophs dont

Light & PhotosynthesisLittle to no starch produces in plants that had zero, or low, light conditions.

You care, because starch indicates sugarsAnd sugars are the energy plants make

exampleWhat happens when you cover up the grass with a doghouse?

That green fuzzy stuff dies quickly!Light also promotes chlorophyl development, although we are not exactly sure how.

Stems leaves etc loose colour when they are stripped of light exposure. And, it does not come back. Why do you care? These plants will stop producing energy from sunlightOnly ~ 1-3% of light hitting plants is converted into chem energy.

The rest bounces off or travels right through the surfaces doing nothing.

Artificial light DOES work (plants absorb mainly visible spectrum)5 kinds of chlorophyllA-eA is most commonB is in algae and higher ordersCde in other algaes

chlorophyllsAct in same way as a catalyst in a reactionDo you know what a catalyst does?

They initiate and control rates of reactionsC02 & water are generally considered the raw materials for photosynth

See light dependent rx handoutConditions affecting phtosynthExternal temps. Extreme heat or cold can stop it.Lengths of light and dark periods. If these are synched photosynth happens effectively. If not, it may slow downFYISpeculation says that early earth plant conditions were prob oxygen deprived. Much of the 20% of atmosphere that is O2 now was created through photosynthchemosynthesisDisect that word. What does it mean?Thats right Tyson chemo (chemical) and synthesis (build)These things can make energy from chemicals (such as sulfides/oxides)Mainly bacteria near soil surfacesThese things are called chemotrophsChemosynth is terribly inefficient and difficult and bacteria are just small dudes so this produces very little org matter

Respiration:Process involving the release of energy for cell activities

Catabolic part of metabolism

In all living cellsSome in cytoplasm, most in mitochondriaMost common fuel is glucose, some starches or amino acids, or lipids

Three parts:Part 1:Glycolosis: in cytoplasmGlucose first broken down.Part 2:Krebs citric acid cycle: Few steps, glucose is completely dismantledPart 3:Electron transportH atoms & electrons moved along a series of carrier molecules. Energy releasedAt this stage, Oxygen available has significant impact

Stages:Glycolosis is anerobic. no Oxy ~5% of overall energyProcess stops @ final stage if no Oxy present.

Krebs: needs some Oxy. About 10 stepsLots of energy forms heat during this phase

Electron transportOxygen most important here

Anaerobic respirationNo/low oxygenLimited number of orgs can do thisBacteria mainlyExample: that food you left sealed in a container that stanks like crazy when you open it prob anearobicResults:Lactic acid in animalsAlcohol in plants

fermentationDoes not produce or release more energyLactic acid fermentation more common to aniumals (especially muscle cells)Leads to muscle soreness and fatigueInability of body to supply oxygen fast enough. Resting allows oxygen to break down lactic acidEver gone running and legs hurt like nuts the next day? Probably contributed to both being out of shape/lazy and lactic acid pooling in your muscles. Ex: sportcenter Ottawa Cenators riding bike after game alwaysBoth alcohol and lactic acid can be deadly in high CnRemember that on Friday night

Release of energy also releases heat on most orgs. Ex: youre a warm blooded thingIn cold blooded animals & plants this is quickly lost to enviroLots of it goes to synthesis of cell parts/substancesAlso motion

summary

PS:Green cells of plantsBegins w lightRequires water and carbon dioxideReleases oxyRadiant E converted to chem EOrganic matter producedRespriation:All living cellsTakes place all the timeRequired org matter and oxygenReleases water and carbon dioxideChem E changed to heat or smaller units of E (ATP)Org matter broken down