Module 2: Essential Biology Chapters 2 & 3

What is an element?

A substance that cannot be broken down by ordinary chemical means.

what are the three atomic components?

Protons (positive), neutrons (neutral), and electrons (negative)

what is the atomic number and atomic mass?

atomic number= # of protons or elections; Atomic mass= protons + neutrons

what is an ionic bond?

Bond formed when atoms transfer electrons and become charged ions.

What is a covalent bond?

bond formed when atoms share electrons

What is a polar molecule?

Molecule with unequal electron sharing causing partial charges

what are hydrogen bonds?

weak bonds between polar molecules like water

what makes a molecule hydrophilic vs. hydrophobic

Hydrophilic = attracted to water; Hydrophobic = repelled by water

 What are the four major classes of large biological molecules?

Carbohydrates, lipids, proteins, nucleic acids

What is dehydration synthesis?

Joining of monomers by removing water

What is hydrolysis?

 Breaking polymers into monomers by adding water

What is the function of disaccharides?

Energy storage

What are polysaccharides?

Long chains of sugar units (storage: starch/glycogen, structural: cellulose)

what are the main types of lipids

fats, phospholipids, steroids

what are proteins made of?

chains of amino acids

what determines a protein’s function?

its three-dimensional shape (conformation)

what are the nucleic acids and their functions

DNA and RNA; store and transmit hereditary information

What are nucleotides made of?

Sugar, phosphate group, nitrogenous base