Living Environment, Mr. Graham

Periodic Table of Elements

What are living things made of? Living things are

composed mainly of carbon, hydrogen, oxygen, and nitrogen.

MacromoleculesMacromolecules are large molecules which

are built by joining smaller molecules together. The smaller molecules are called monomers, which join together to form polymers.

Organic vs. Inorganic MoleculesOrganic – Contains both C

and HInorganic – Doesn’t contain

both C and HExamples:

Carbohydrates (Sugars)Lipids (Fats)ProteinsNucleic Acid (RNA,

DNA)

Examples:Water (H2O)Carbon Dioxide (CO2)Oxygen (O2)Salts (i.e. NaCl)Minerals

Four Organic CompoundsCarbohydratesLipids (Fats)ProteinsNucleic Acid

Building large molecules of lifeChain together smaller molecules

building block molecules = monomers

Big molecules built from little moleculespolymers

Building large organic moleculesSmall molecules = building blocks

Bond them together = polymers

Making and Breaking of POLYMERS

Cells link monomers to form polymers by dehydration synthesis (building up)

Short polymer Unlinked monomerRemoval ofwater molecule

Longer polymer

Building important polymerssugar – sugar – sugar – sugar – sugar – sugar

nucleotide – nucleotide – nucleotide – nucleotide

Carbohydrates = built from sugars

Proteins = built from amino acids

Nucleic acids (DNA) = built from nucleotides

aminoacid

aminoacid–

aminoacid–

aminoacid–

aminoacid–

aminoacid–

Example of synthesis

amino acids protein

amino acids = building blockprotein = polymer

Proteins are synthesized by bonding amino acids

How to take large molecules apart Hydrolysis (Digestion)

taking big molecules apartgetting raw materials

for synthesis & growthmaking energy (ATP)

for synthesis, growth & everyday functions

+

ATP

Making and Breaking of POLYMERS

Polymers are broken down to monomers by the reverse process, hydrolysis (hydro ~ add water; lysis ~ to split)

Addition ofwater molecule

Example of digestion

starch glucose

ATP

ATP

ATP

ATP

ATP

ATPATP

Starch is digested to glucose

Carbohydrates – breads, pastas, and potatoes.

Living things use carbohydrates as their main source of energy.

There are three main types of carbohydrates.Monosaccharide -

glucoseDisaccharides - sucrosePolysaccharides –

starch, cellulose, and glycogen.

CarbohydratesBuilding block molecules =

sugarsugarsugarsugarsugarsugarsugarsugar

sugar - sugar - sugar - sugar - sugar

sugars

Building carbohydratesSynthesis

|glucose

|glucose

1 sugar = monosaccharide

2 sugars = disaccharide

|maltose

mono = onesaccharide = sugar

di = two

BIG carbohydratesPolysaccharides

large carbohydrates starch

energy storage in plants potatoes

glycogen energy storage in animals

in liver & muscles cellulose

structure in plants cell walls

chitin structure in arthropods & fungi

exoskeleton

poly = many

Cellulose Cell walls in plants

herbivores can digest cellulose wellmost carnivores cannot digest cellulose

that’s why they eat meat to get their energy & nutrients

cellulose = roughage stays undigested keeps material

moving in your intestines

Cellulose Cell walls in plants

herbivores can digest cellulose wellmost carnivores cannot digest cellulose

that’s why they eat meat to get their energy & nutrients

cellulose = roughage stays undigested keeps material

moving in your intestines

Proteins – meats such as steak, and chicken. Proteins have many

different functions. The monomer that builds proteins is called an amino acid. Enzymes – catalyze

chemical reactions. Antibodies (immune

system) – protect the body from pathogens.

Hormones – chemical messengers.

Receptor Molecules – cellular communication

pepsin

For proteins: SHAPE matters!

collagen

Proteins fold & twist into 3-D shapethat’s what happens in the cell!

Different shapes = different jobs

hemoglobingrowthhormone

Amino acids can be linked by peptide bonds

Cells link amino acids together by dehydration synthesis

The bonds between amino acid monomers are called peptide bonds

Dehydrationsynthesis

Amino acid Amino acid

PEPTIDEBOND

Dipeptide

Lipids – bacon, burgers, and pizza. Lipids can be used to store energy. Some are

important parts of biological membranes (cell membranes)

Saturated vs. Unsaturated

LipidsFunction:

energy storage very concentrated twice the energy as carbohydrates!

cell membranecushions organsinsulates body

think whale blubber!

2003-2004

Other lipids in biologyCell membranes are made out of lipidsphospholipidsheads are on the outside touching water

“like” watertails are on inside away from water

“scared” of waterforms a barrier

between the cell & the outside

Nucleic AcidsDNA and RNA are

nucleic acids. Deoxyribonucleic acid and ribonucleic acid. Nucleic acids store and transmit hereditary information.

Nucleotides are the monomer of nucleic acids.

Nucleotide chainsNucleic acids nucleotides chained into

a polymer DNA

double-sideddouble helixA, C, G, T

RNA

single-sidedA, C, G, U

phosphate

sugar N base

phosphate

sugar N base

phosphate

sugar N base

phosphate

sugar N base

strong bonds

RNA

Indicators – a substance that changes color in the

presence of a specific chemical. Lugol’s Solution (Iodine)

Tests for starchBenedict’s Solution

Test for monosacchrides (i.e. glucose)Litmus Paper

Tests for Acids and BasesBromothymol Blue

Test for Carbon Dioxide

Lugol’s SolutionYellow = no starchBrown/Black =

starch

Benedict’s SolutionBlue = no glucoseBrown = glucoseThe solution with

Benedict’s solution MUST be heated for 3-5 minutes in order to properly conduct this test.

Negative Test

Positive Test

Bromothymol BlueBlue = basic (> 7.6)Green = neutral

(~7.0)Yellow = acidic (<

6.0)