ch. 3 sept 25: chemical groups

properties of organic compounds are based on

• size and shape of carbon skeleton

• atoms attached to the skeleton

chemical group

Atoms that are attached to the carbon skeleton

• can affect function

what chemical group is this, give an example

hydroxyl: H attached to O

• eg. alcohols

what chemical group is this, give an example of where they are found

carbonyl: C attached by a double bond to an O atom

• found in simple sugars

what chemical group is this, is it acidic or basic?

carboxyl: C double bonded to an O atom and OH

• it donates H, making it acidic

what chemical group is this

amino group: nitrogen bonded to two H

• pick up H form a solution

• aka amines

what chemical group is this?

phosphate group: phosphorous atom bonded to four O atoms

• often ionized bc O atoms are negative

what chemical group is this, what does it affect?

methyl group: C bonded to three H atoms

• affects gene expression

which chemical groups are polar?

• hydroxl

• carbonyl

• carboxyl

• amino

• phosphate

what chemical groups are non polar, are they reactive

• methyl group

• not reactive

affects shape of molecule

4 main classes of molecules

1. carbs

2. lipids

3. proteins

4. nucleic acids

macromolecules

very large molecules

polymers

Small molecules joined together in large chains of similar building blocks

• macromolecules are made of large polymers

• great diversity based on arrangement of monomers

monomers

building blocks of polymers

what reaction makes a polymer?

dehydration reaction: removing water so 2 molecules bond

• removing OH from one molecule, removing H from the other

what reaction breaks polymers, making them monomers?

hydrolysis: adding water to break polymer

• OH attaches to one monomer and H attaches to the other

enzymes

specialized macromolecules that speed up chemical reactions in cells

carbohydrates

• can be small or large

• most are hydrophilic (many hydroxyl groups)

monosaccharides

• carbohydrate

• simplest of sugars, eg. glucose and fructose found in honey

• CHO in 1:2:1 ratio

what chemical groups do sugars typically contain?

• 1 carbonyl

• multiple hydroxyls

typically, what shape do monosaccharides with 3-7 carbons take?

rings

• most are pentoses (5 carbons) and hexoses (6 carbons)

the names of enzymes that break sugars apart end in…

“ase”

why are monosaccharides the main fuel for cells?

energy is released when they are broken down

disaccharides

• 2 monosaccharides linked together

• eg. maltose, sucrose

what is the function of polysaccharides, how are the monosaccharides linked together?

storage molecules and structural compounds

• linked via dehydration synthesis

4 common types of polysaccharides

1. starch

2. glycogen

3. cellulose

4. chitin

starch

• storage polysaccharide in plants (carbohydrate bank)

• coil into helical shape that are either branched or unbranched

• most animals have enzymes to break it down (amylase)

glycogen

• glucose storage molecule in animals (mostly in liver and muscle cells)

• highly branched

• broken down by liver and muscle cells if needed

cellulose

• polymer of glucose

• most abundant organic compound on earth

• cable-like microfibrils (layers of strings)

• some microorganisms can break it down

chitin

• structural polysaccharide used by insects and crustaceans

• builds exoskeleton

• also found in cell wall of fungi

how does water dissolve ionic compounds

attractions pull ions away from each other

how does water dissolve non ionic compounds

water surrounds compound, forming hydrogen bonds with the polar regions