Life10e Ch03 Lecture-Proteins_ Carbohydrates_ and Lipids.

Proteins, Carbohydrates, Lipids, Nucleic acids

Molecules that make up living

organisms

Proteins

combinations of 20 amino

acids

Carbohydrates

sugar monomers

(monosaccharides) are linked to

form polysaccharides

Nucleic acids

four kinds of nucleotide

monomers

Lipids

noncovalent forces maintain

interactions between lipid

monomers

Macromolecules

polymers with

molecular weights >1,000

Isomers

molecules with the same

chemical formula, but atoms are

arranged differently

Structural isomers

differ in how their

atoms are joined together.

cis-trans isomers

different orientation

around a double bond.

Optical isomers

occur when a carbon

atom has four different atoms or

groups attached to it

Substances Found in Living Tissues

Polymers are formed

in condensation

reactions

Monomers are joined by

covalent

bonds; energy must be added

dehydration reactions

water is removed

hydrolysis reactions

hydro, “water”; lysis, “break” - Hydrolysis releases energy

condensation reactions

water is added

Polypeptide chain

single, unbranched

chain of amino acids.

Amino acids have

carboxyl and

amino

D-amino acids

dextro, right

L-amino acids

(levo, left)

Condensation

Reaction where water is introduced as a by-product, and energy is released.

Hydrolysis

A reaction where water is released and energy is reabsorbed

Enzymes

Catalyst to speed up biochemical reactions

Structural proteins

Provide physicals stability and movement

Defensive proteins

Recognize and responds to nonself substances

Signaling proteins

Control physiological processes (eg. hormones)

Receptors Proteins

Receive and respond to chemical signals

Membrane transporters

Regulate passage of substances across cellular membranes

Storage proteins

Stores amino acids for later use

Transport protein

Bind and carry substances within the organism

Gene regulatory proteins

Determine the rate of expression within a gene