subatomic particlechargelocation proton +nucleus neutron nonenucleus electron - surrounds nucleus...

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• Subatomic particle Charge Locationproton + nucleusneutron none nucleuselectron - surrounds nucleus

Atomic number (#)= number of protons (=number of electrons in neutral atom)

Mass number (AM)= number of protons + number of neutrons

Macroelements- need large quantities6 elements make up 98% by mass

C, H, N, O, P, SMicroelements (or trace elements)-Need very small amounts but critical!!

ex. Selenium (Se) is an antioxidant that helps prevent cell damage from free radicals, also help thyroid function and boost immune system

Radioactive Isotopes: nucleus decaysUsed in medical research

Compounds are different from the elements that make them up!!

Properties of atoms due to:electronegativityvalence electronsconfigurationsize

Ex. Ions

• Bonds (ionic and covalent)- lose, gain or share electrons in order to fill valence shell (stability)– All atoms want 8 e- in their outermost shell

Due to electronegativity!•Ionic- >1.7•Polar covalent- 0.4- 1.7•Covalent- < 0.4

• Hydrogen bonds- attraction of H to partial negative charge (due to

polar covalent bonds between oxygen and hydrogen)

Degrade with heat,Change in pH, orChemical treatments!

Hydrogen withoxygen, nitrogen,etc.

Weakbond-Strongforce

And remember: Structure determinesAnd remember: Structure determines Function!!!!!Function!!!!!

Should we control a chemical that:•Causes excessive sweating and vomiting.•Is a major component in acid rain.•Can cause severe burns in its gaseous state.

•Accidental inhalation can kill you.•Contributes to erosion.•Decreases the effectiveness of car brakes.•Has been found in tumors of terminal cancer patients.

What is the chemical?Dihydrogen monoxide

H2O H+ + OH-

Pure water ion conc. Is 10-7 MAdding solutes disrupts balanceAcid- adds H+

Base- reduces H+ (adds OH-)

•Log based•Acids pH <7•Neutral pH=7•Base pH >7•[H+] + [OH-] = 14

•Properties of both acid and base•Resist pH shifts•Very important in living organisms!

2006- The movement of water through vascular plantsis important to their survival.

a. Explain the mechanism of water movementthrough vascular plants during transpiration. Include a discussion of how the anatomy ofvascular plants and the properties of watercontribute to this process.

2003B- Water is important for all living organisms.The functions of water are directly related to its physicalpropertiesa. Describe how the properties of water contribute to TWO of the following

* transpiration* thermoregulation in endotherms* plasma membrane structure

Forms 4covalentbonds

Tetrahedralmolecular shape

Bonds easilyto itself!

Structural

Geometric

Enantiomers

Built of monomers (subunits)

•Makes covalent bonds (stores energy)•Joins two monomers

Water removed

Breaks bonds (releases energy)

Water added

2003B- Water is important for all living organisms.The functions of water are directly related to its physical properties.

b. Water serves as a reactant and a product in the carbon cycle. Discuss the role of

water in the carbon cycle.

•C, H, O in 1:2:1 ratioC, H, O in 1:2:1 ratio•Used for fuel, structure, and receptorsUsed for fuel, structure, and receptors•Simple or complexSimple or complex

•Storage and structure

•HydrophobicHydrophobic•C, H, O components- high in CC, H, O components- high in C•High in energyHigh in energy

•“Full”- no double bonds•Straight chained•Solid•Found in fats

•One or more C=C bonds (can accept more H•Bent chains•Liquid•Found in oils

•Energy storage, insulation, cushions organs

•Only 2 fatty acids•Hydrophilic head, hydrophobic tail•Membrane bilayers

•Four fused rings with functional groupsFour fused rings with functional groups•Ex. Cholesterol and hormonesEx. Cholesterol and hormones

• C, H, O, N, sometimes S• Molecular tools• Structure, enzymes, antibodiesTransport, movement, receptors, hormones• Chains of amino acids linked by peptidebonds

Peptide bond

•Gives protein its properties

•Made of nucleotides (nitrogen base, pentose sugar, phosphate)•Informational•C, H, O, N, P

•Deoxyribose•Double stranded•Thymine•Makes up genes

•Ribose•Single stranded•Uracil•Structure and protein synthesis

“Spontaneous”

Not “Spontaneous”

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