Atoms & Life Atoms & Life SubstancesSubstancesSection 6.1 & 6.3Section 6.1 & 6.3

Atomic Structure 6.1Atomic Structure 6.1 NucleusNucleus = center of = center of

an atom, contains an atom, contains protons protons ((pp+ + positively positively charged)charged) and and neutrons neutrons ((nnº º neutral)neutral)

Electrons Electrons ((eˉeˉ) are ) are negatively charged negatively charged particles that particles that surround the nucleussurround the nucleus

Atoms are neutral Atoms are neutral because they contain because they contain equal numbers of equal numbers of protonsprotons and and electronselectrons

Biomolecules (6.3)Biomolecules (6.3)

These are the These are the moleculesmolecules required by required by living thingsliving things 1. Carbohydrates1. Carbohydrates 2. Proteins2. Proteins 3. Lipids3. Lipids 4. Nucleic Acids4. Nucleic Acids

(There are other types of molecules too!!!)(There are other types of molecules too!!!)

Organic CompoundsOrganic Compounds = contain carbon, = contain carbon, all all biomoleculesbiomolecules are organic are organic

MonomerMonomer = a building block, smaller = a building block, smaller subunits subunits

PolymerPolymer = made up of lots of monomer = made up of lots of monomer subunitssubunits

1.1. CARBOHYDRATES CARBOHYDRATES pg. 158pg. 158

Source of energySource of energy Structural materialsStructural materials Monosaccharides Monosaccharides & & PolysaccharidesPolysaccharides

Monosaccharide CarbsMonosaccharide Carbs They’re They’re MonomersMonomers =1 Carbohydrate =1 Carbohydrate GlucoseGlucose = main source of energy for = main source of energy for

cells, diabetics need to monitor glucose cells, diabetics need to monitor glucose levelslevels

Polysaccharide Carbs Polysaccharide Carbs

PolysaccharidePolysaccharide = 3 = 3 or more or more monosaccharidesmonosaccharides GlycogenGlycogen = how = how

animals store glucoseanimals store glucose StarchStarch = how plants = how plants

store glucosestore glucose CelluloseCellulose = =

polysaccharide, polysaccharide, provides plants with provides plants with structurestructure

2. 2. PROTEINS PROTEINS pg. 161pg. 161 Hair, horns, nails, Hair, horns, nails,

skin, muscleskin, muscle Act as Act as biological biological

catalystscatalysts ( (enyzmesenyzmes)) which help to kick which help to kick start reactions in the start reactions in the bodybody

Amino AcidsAmino Acids Protein Protein monomermonomer 20 different amino 20 different amino

acidsacids Peptide BondPeptide Bond = =

connects amino connects amino acidsacids

http://www.biotopics.co.uk/as/aminocon.html

PolypeptidePolypeptide = long = long chain of amino chain of amino acidsacids

Enzymes Enzymes Enzymes change the rate of reactions in the bodyEnzymes change the rate of reactions in the body Help cells reproduce, digest food, get rid of waste, Help cells reproduce, digest food, get rid of waste,

make new biomoleculesmake new biomolecules Active SiteActive Site = a section of the enzyme shaped to = a section of the enzyme shaped to

fit a specific substratefit a specific substrate SubstrateSubstrate = something that’s being broken apart = something that’s being broken apart

or made (or made (catalyzedcatalyzed)) http://www.lpscience.fatcow.com/jwanamaker/animations/Enzyme%20activity.htmlhttp://www.lpscience.fatcow.com/jwanamaker/animations/Enzyme%20activity.html http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/

animation__how_enzymes_work.htmlanimation__how_enzymes_work.html

3. 3. LIPIDSLIPIDS pg. 160 pg. 160 InsolubleInsoluble = Don’t dissolve in water = Don’t dissolve in water Best for storing energyBest for storing energy Insulation, protective coveringsInsulation, protective coverings Major part of cell membranesMajor part of cell membranes

Saturated & Unsaturated Saturated & Unsaturated Fats Fats

Saturated Fat Saturated Fat = found = found in butter, red meat in butter, red meat (solid at room (solid at room temperature), temperature), saturated saturated with hydrogenwith hydrogen

Unsaturated Fat Unsaturated Fat = = vegetable fats (liquid at vegetable fats (liquid at room temperature)room temperature)

PhospholipidsPhospholipids Cell membranesCell membranes made up of two layers of made up of two layers of

phospholipids, forms a barrierphospholipids, forms a barrier Keeps things that are supposed to be out, out of the Keeps things that are supposed to be out, out of the

cellcell Keeps things that are supposed to be in, in the cellKeeps things that are supposed to be in, in the cell

2 fatty acids attached to glycerol, and a phosphate 2 fatty acids attached to glycerol, and a phosphate groupgroup

Phosphate

Lipids

PracticePractice

What percent of your body is made of What percent of your body is made of water?water?

Explain why a cell needs a structure that Explain why a cell needs a structure that helps it maintain water levels inside? helps it maintain water levels inside? What could happen to the cell if this What could happen to the cell if this structure wasn’t working properly?structure wasn’t working properly?

Other types of LIPIDS Other types of LIPIDS besides fats…besides fats…

WaxWax StructuralStructural Makes a coat on plants for water proofingMakes a coat on plants for water proofing

SteroidsSteroids Hormones that cause physical changes in Hormones that cause physical changes in

the bodythe body

4. 4. NUCLEIC ACIDS NUCLEIC ACIDS pg. 163pg. 163

Store and transfer info in Store and transfer info in the cellthe cell

NucleotideNucleotide = = monomermonomer of nucleic acidsof nucleic acids

2 kinds of nucleic acid 2 kinds of nucleic acid polymerspolymers: : DNADNA = = ddeoxyriboeoxyribonnucleic ucleic

aacidcid RNARNA = = rriboibonnucleic ucleic aacid cid