Chapter 3: The Chemical Building Blocks of Life | D.C. Bio

Carbon

Must contain ___ to be considered organic

Carbon can contain up to ___ covalent bonds

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Functional Groups

Specific molecular groups that bond to carbon-hydrogen skeletons.

Purpose of Functional Groups

Influence the behavior of the entire molecule in reactions.

Isomers

Compounds with the same molecular formula but different structural arrangements. Isomers can have varying physical and chemical arrangements.

Dehydration Synthesis

Used to build macromolecules by removing water molecules to form bonds between monomers.

Hydrolysis

Used to break down large molecules by adding water molecules to split bonds between monomers.

Monomers are joined to form ________.

Polymers

Polymers are broken down to _______.

Monomers

Carbohydrates

Molecules with a 1:2:1 of C, H, and O

Characteristic of carbohydrates

Good energy storage molecules.

Examples of Carbohydrates

Sugars, starch, glucose

Monosaccharides

Simplest units of carbohydrates and the simplest form of sugar. Ex. Glucose and Fructose.

Disaccharides

Two monosaccharides linked together by dehydration synthesis.

• Purpose: transport sugar or for energy storage

• Examples: Sucrose, lactose, maltose

Polysaccharides

Long chains of monosaccharaides linked through dehydration synthesis.

• Energy Storage: Plants use starch. Animals use glycogen.

• Structural Support: Plants use cellulose. Arthropods and fungi use chitin.

Nucleic Acids

Made up of monomers of nucleotides that are connected by phosphodiester bonds.

Nucleotides are composed of ______+_______+_______.

Sugar, Phosphate, Nitrogen Base

Two Families of Nitrogen Bases

Purines and Pyrimidines

Purines

Adenine and Guanine

Pyrimidines

Thymine, Cytosine, Uracil

DNA

Encodes information for amino acid sequence of proteins within a sequence of bases.

Base-Pairing Rules

A = T(or U in RNA)

C = G

RNA

Uses information in DNA to specify sequence of amino acid in proteins. Contains the sugar, ribose, and the base, uracil. Single Polynucleotide strand.

ATP

The primary energy currency of the cell.

NAD+ & FAD

Serve as electron carriers for many cellular reactions.

Protein Functions:

Enzymes catalyst, defense, transport, support, motion, regulation, storage

Amino acids are ____

Monomers & composed of one or more long, unbranched chains.

Parts of an Amino Acid

Central carbon atom, amino group, caroboxyl group, single hydrogen, variable R group.

Four Levels of Protein Structure

Primary Structure: sequence of amino acids(have come straight out of ribosome.)

Secondary Structure: interaction of groups in the peptide backbone. Helps support the shape of protein. Two main shapes: helix or sheet.

Tertiary Structure: globular structure; hydrophobic inside, hydrophilic outside.

Quaternary Structure: Subunits(polypeptide chains) come together give this structure.

Chaperones

Help proteins fold correctly

Denaturation

Protein loses its structure by unfolding, promptly losing its function. Due to environmental conditions: pH, temperature, ionic concentration of solution.

Dissociation

Subunits of protein with a quaternary structure separate but do not lose their function.

Lipids

• Insoluble in water

• High proportion of nonpolar C—H bonds cause the molecule to be hydrophobic.

• Ex. Fats, oils, waxes, terpenes, steroids, and some vitamins

Fat Molecules

Triglycerides : composed of one(1) glycerol and three(3) fatty acids.

Fatty Acids: need not to be identical; the chain length varies.

Saturated Fat

No double bonds between carbon atoms.

• Higher melting point

• Animal origin.

Unsaturated Fat

One or more double bonds.

• Low melting point

• Plant origin

Trans Fat

Produced industrially

Phospholipids

Composed of glycerol, two(2) fatty acids — nonpolar “tails” and a phosphate “head”. Form all biological membranes.

Micelles

Lipid molecules orient with polar(hydrophilic) head toward water and nonpolar tails away from water.

• phospholipid bilayer