How Valid Are The Results?Science cannot always yield “absolute truth” to the Science cannot always yield “absolute truth” to the

theories or laws provided. But they can:theories or laws provided. But they can:

1)1) Disprove ideas, theories, or lawsDisprove ideas, theories, or laws

2)2) Establish that ideas, theories, or laws have a Establish that ideas, theories, or laws have a high validity or probability of being truehigh validity or probability of being true

Consensus Science

Frontier Science

Consist of theories and laws that are widely

accepted in the scientific community

“Breakthroughs” – a tentative hypothesis

and controversial data & models

A system is a set of components that function and interact A system is a set of components that function and interact in some regular and theoretically understandable manner.in some regular and theoretically understandable manner.

SYSTEMS:

Key componentsKey components

flows flows (throughputs)(throughputs)

inputs &inputs &

outputsoutputs

Feedback loops are when outputs of energy fed back into a system cause the system to do more of what it was doing (positive) or less (negative)

HomeostasiHomeostasis!s!

AccelerateAccelerates Changes Change

As the baby (stimulus) moves toward the birth canal, pressure receptors within the cervix send

messages to the brain to produce oxytocin. Oxytocin stimulates the muscles in the uterine wall to

contract stronger.The contractions intensify and increase until the stimulus to the pressure receptors

ends.

EXAMPLE = POSITIVE FEEDBACK LOOP

1 + 1 = 5???1 + 1 = 5???

Synergy = when processes & Synergy = when processes & feedbacks in a system interact to feedbacks in a system interact to amplify the resultsamplify the results

Time DelaysTime Delays:: very complex systems can show very complex systems can show dramatic time delays between the input of a stimulus dramatic time delays between the input of a stimulus and the response. and the response.

Time delays can cause a problem to build up Time delays can cause a problem to build up slowly until the system reaches a slowly until the system reaches a threshold levelthreshold level and there is a and there is a fundamental breakdown in the system.fundamental breakdown in the system.

Outer electrons are known as valence electrons.

Valence electrons are available in bonding with other atoms.

ATOMS REVIEW - You are responsible for knowing all structure &

function of atoms!!

Many of the things you are familiar with are carbon Many of the things you are familiar with are carbon compound (sugar, plastics, vitamins, most compounds in your compound (sugar, plastics, vitamins, most compounds in your body)body)

Almost all of them (except CHAlmost all of them (except CH44) have between 2 - ) have between 2 -

1,000’s of carbons attached by covalent bonded to 1,000’s of carbons attached by covalent bonded to each other and one or more of the following atoms: each other and one or more of the following atoms: hydrogen, oxygen, nitrogen, sulfur, phosphorus, hydrogen, oxygen, nitrogen, sulfur, phosphorus, chlorine, and fluorine.chlorine, and fluorine.

Synthetic or Natural

Hydrocarbons:Hydrocarbons: methane methane (CH4),, propane propane(C3H8), butane, butane(C3H10)

Chlorinated HydrocarbonsChlorinated Hydrocarbons: DDT, many insecticides, : DDT, many insecticides, PCB’s, solvents such as chloroformPCB’s, solvents such as chloroform

Carbohydrates:Carbohydrates: Carbon, Hydrogen, Oxygen covalently Carbon, Hydrogen, Oxygen covalently bonded (sugars) Cellulose, Glucose, Starchesbonded (sugars) Cellulose, Glucose, Starches

Chlorofluorocarbons Chlorofluorocarbons – CFC’s ; Freon – CFC’s ; Freon (CCl2F)

MONOMERS

POLYMERPOLYMERSS

make

AMINO ACIDS

NUCLEOTIDES

PROTEINSPROTEINS

NUCLEIC ACIDSNUCLEIC ACIDS

SO…What inorganic compounds are important in the SO…What inorganic compounds are important in the ecosystem?ecosystem?

WATER!! WATER!! Carbon Monoxide (CO) Carbon Monoxide (CO)

NaCl, Nitrous Oxide (NNaCl, Nitrous Oxide (N22O)O) Carbon Dioxide (COCarbon Dioxide (CO22) )

Nitric Oxide (NO) Nitric Oxide (NO) Sulfur Dioxide (SOSulfur Dioxide (SO22) )

Nitrogen Dioxide (NONitrogen Dioxide (NO22) ) Ammonia (NHAmmonia (NH33))