Chapter 3

What are almost all molecules in a cell composed of ?

Carbon

What can carbon form?

Large and complex molecules

Organic molecules

Molecules with carbon

How do carbon skeletons vary?

Length, double bonds, branching, rings

Why are isomers with four different partners important in the pharmaceutical industry?

Using 2 different isomers of a drug can be harmful

Hydrocarbons

Molecules consisting of only carbon and hydrogen

Isomers

Compounds with the same formula but different structural formulas

How can isomers be created?

From differences in spatial arrangements

How do testosterone and estrogen differ?

In their groups of atoms

Function groups

Affect a molecule's function by participating in chemical reactionsWha

What are two properties of functional groups?

Polar and hydrophyllicW

What are the function groups?

Hydroxyl, Carbonyl, Carboxyl, Amino group, phosphate, methyl group

Hydroxyl group

Contain hydrogen bonding to oxygen, ie ethanol and other alcohols

Hydroxyl formula

-OH

Carbonyl

Carbon double bonded to oxygen

What are simple sugars made of

Hydroxyl and Carbonyl groups

Carbonyl formula

>C=O

Carboxyl

Carbon double bonded to oxygen and hydroxyl, and can act like an acidCarb

Carboxyl formula

-COOH

Amino group

Nitrogen bonded with two hydrogens and can act like a base after being ionized

What do amino acids contain?

Amino and carboxyl groups

Amino formula

-NH2

Phosphate

Phosphorous atoms bonded to four oxygen atoms and unequally ionizedW

What is phosphate involved in?

The transfer of energy

Phosphate formula

-OPO32-

Methyl group

Carbon bonded to three hydrgen

What composes DNA?

Methyl groups

Methyl formula

-CH3C

Classes of molecules

Carbohydrates, lipids, proteins, and nucleic acid

Macromolecules

Carbohydrates, proteins, nucleic acids

How do cells make macromolecules?

By joining smaller molecules into chains called polymers

Polymer

A long molecule consisting of many identical building blocks strung together

Monomers

Building blocks of polymers

How do cells link monomers together?

Using dehydration reaction

Dehydration reaction

A reaction that moves a molecule of water as two molecules bond together

Hydrolysis

Reverse dehydration process

What to dehydration and hydrolysis reactions require to make or break bonds?

Enzymes

Enzymes

Specialized macromolecules that speed up chemical reactions in cells

How many components make up cells?

40-50

How many components makeup proteins?

20 kinds of amino acids

What composes DNA?

4 kinds of monomers called nucleotides

Carbohydrates

A class of molecules ranging from small sugar molecules to large polysaccharides

Monosaccharides

Simple sugars and the monomers of carbohydrates

What are glucose and fructose

Single unit sugars that use dehydration to form polysaccharides

Formula for monosaccharides

CH2O

Two trademarks of a sugar

Hydroxyl + Carbonyl group

How long can monosaccharides carbon structures be?

3-7 carbons long

What are the most common sugars?

Pentose and hexoseM

What are the main fuel components for cellular molecules

Monosaccharides, mainly glucose

What happens when cells break down glucose

They release energy

How do cells use the carbon skeletons of monosaccharides?

They make other kinds of organic molecules like amino and fatty acids

Disaccharides

Two monosaccharides bonded by dehydration reactions

What is the most common disaccharide

Sucrose composed of a glucose monomer and fructose

Polysaccharides

Macromolecules composed of polymers made of hundreds of thousands of monosaccharides linked by dehydration reactions

Lipid

Neither huge macromolecules or polymers built from similar monomers

Fat

Large lipids made from two kinds of smaller molecules: glycerol and fatty acids

Unsaturated Fatty Acid

Contains one or more double bond and have kinks in their tails which prevent them from packing tightly together

Saturated Fatty Acid

Tails lack double bonds so they compact closely together

Polysaccharides

Starch, glycogen, cellulose, chitin

Starch

Unbranched storage molecules for plant cells

Glycogen

Highly branched molecules used for energy storage in liver and muscle cells

Cellulose

Polymer made of glucose made to structure plant cell walls

What is the most abundant organic compound?

Cellulose

Chitin

Structural polysaccharide used by insect and crustaceans for exoskeletons, and fungi for their cell walls

Fats

Lipids that are mostly energy storage molecules made from glycerol and fatty acids, and has 3 carbons and a hydroxyl and a hydrocarbon

What are polysaccharides

Hydrophillic because they contain storage groups

Types of lipids

Fats, phosophlids, steroids

What is the main function of fat

Energy storage

Composition of fat

3 fatty acids + glycerol

Unsaturated fatty acid

Hydrocarbon chain containing double bonds, which create kinks and bends, mostly fish and plant fats

Saturated fatty acids

No double bond in hydrogen, mostly animal fats

Phospholipids

Structurally similar to fats, except that they contain only two fatty acids attached to glycerol instead of three

Phospholipid structure

Phospholipid head

Polar and hydrophillic

Phospholipid tail

Nonpolar and hydrophobic

How are phospholipids in water structured?

In a double layered sheet, where the tails cluster together in the center of the sheet, excluded from water, and the heads face the watery environment on either side of the resulting membrane

Steroids

Lipids in which the carbon skeleton contains four fused rings

Steroids structure

Cholesterol

A steroid that is a common component in animal cell membranes and is also the precursor for making other steroids, including sex hormones

Composition of phospholipids

Two fatty acids and a phosphate group attached to glycerol

What do amino acids contain?

Amino and carboxyl group, hydrogen atom, and variable group covalently bonded to carbon atom

General structure of amino acid

R/Variable group

Consists of one or more carbon atoms with various functional groups attached.

Hydrophobic amino acids

Nonpolar R group

Hydrophilic amino acids

Charged R groups

Peptide bonds

Cells join amino acids together in a dehydration reaction that links the carboxyl group of one amino acid to the amino group of the next amino acid as a water molecule is removed

Dipeptide

Two amino acids

Peptide bond formation

What are the stitches that coil and fold a polypeptide chain into its unique three-dimensional shape?

Hydrophobic amino acids may cluster together in the center of a globular protein, while hydrophilic amino acids face the outside, helping proteins dissolve in the aqueous solution of a cell.

What helps determine a protein's shape?

Hydrogen bonds and ionic bonds between hydrophilic R groups and covalent bonds called disulfide bridges between sulfur atoms in some R groups.

What generally determines a protein's shape?

The unique sequence of the various types of amino acids in a polypeptide

Primary structure of protein

The precise sequence of amino acids in the polypeptide chain

Secondary structure of a protein

Segments of the chain coil or fold into local patterns

Tertiary structure

The overall three-dimensional shape of a protein

Quaternary structure

Proteins with more than one polypeptide chain

Protein shape

Gene

The discrete unit of inheritance that programs the amino acid sequence of a polypeptide

DNA

Deoxyribose nucleic acid

RNA

Ribonucleic acid

What nucleic acids are in genes?

RNA and DNA