Chapter 2 Review
What is an atom?
The smallest basic unit of matter.
What is mass?
The amount of matter in an object.
What is matter?
Anything that takes up space and has mass.
What are all living things based on?
Atoms and their interactions.
What is the middle part of the atom called?
Nucleus
What is contained within the nucleus?
Protons and Neutrons
What are the three subatomic particles and their charges?
Electrons (-) Protons (+) Neutrons (neutral)
What is a compound?
Made of atoms of different elements bonded together.
Provide two examples of compounds.
Water, carbon dioxide, …
What is an ion?
An atom that has gained or lost one or more electrons. (an atom with a charge)
What forms between oppositely charged ions?
Ionic bond
What is a covalent bond?
A bond formed between atoms sharing electrons.
What is a polar molecule?
A molecule with a slightly charged region.
What is a non-polar molecule?
A molecule that does not have a slightly charged region.
What do hydrogen bonds form between?
Slightly positive hydrogen atoms and slightly negative atoms.
Hydrogen bonds are responsible for what three important properties of water?
High specific, cohesion, adhesion
What is high specific heat?
The amount of energy 1 gram of a substance must absorb or release to change its temperature 1˚C
What is cohesion?
Like molecules sticking together; mutual attraction
What is adhesion?
The tendency of dissimilar particles or forces to cling to one another.
What is a solution?
Something that is formed when one substance dissolves in another.
What does homogenous mean?
The same throughout
What is a homogenous mixture?
A mixture that is uniform throughout; all areas are the same composition
What is a solvent?
Something that dissolves other substances.
What is a solute?
Something that is dissolved in a substance.
What will polar solvents dissolve?
Polar solutes.
What will non-polar solvents dissolve?
Non-polar solutes
What will happen between polar substances and non-polar substances?
Generally, they remain separate.
What will an acid release when it is dissolved in water?
Hydrogen ions
What will a base remove from a solution?
Hydrogen ions
What is neutral pH?
7
What are the three general structures of carbon-based molecules?
Straight chain, branched chain, ring
What is a monomer?
Individual subunits.
What is a polymer?
A group of monomers put together.
What are the 4 categories of organic compounds?
Carbohydrates, lipids, proteins, nucleic acids.
What is the monomer of a carbohydrate?
monosaccharide
Name three monosaccharides.
Glucose, fructose, galactose
What is the chemical formula for glucose?
C6H12O6
What is made from combining two monosaccharides?
disaccharide
What are three disaccharides?
Sucrose, lactose, maltose
What is the chemical formula for a disaccharide?
C12H22O11
What is a dehydration reaction?
A reaction that involves the removal of a water molecule.
What suffix means carbohydrate (or sugar)?
ose
What is a polysaccharide?
A group of monosaccharides put together.
What is cellulose?
A sugar that is the primary strengthening ingredient in plant cell walls.
What is the identifying characteristic of a lipid?
Non-soluble in water
What are the three categories of lipids?
Triglycerides, waxes, steroids.
Give two examples of triglycerides.
Table oil, baby oil, synovial fluid, sebum,…
Give two examples of a wax.
Vernix, smegma, cerumen, cuticle
Give two examples of a steroid.
Testosterone, progesterone, estrogen, dexamethasone, cortisone.
What are the functions of a fat?
Insulation, protection, storage of energy
What is the monomer of a protein?
Amino acid
How many amino acids are there?
22
How many amino acids are essential?
9
What does essential amino acid mean?
It must be taken in through your diet.
What are proteins used for?
Growth and repair
What are enzymes a derivative of?
Proteins
What is an enzyme?
A biological catalyst
What is a catalyst?
Something that causes a reaction to occur without actually being involved in the reaction itself.
What is amylase?
The enzyme in saliva that breaks down starch.
What does the ending “-ase” mean?
enzyme
What does the ending “-one” mean?
Steroid
What is the monomer of a nucleic acid?
Nucleotide
What are the nitrogen bases found in DNA?
Cytosine, thymine, adenine, guanine
What are the nitrogen bases found in RNA?
Uracil, cytosine, adenine, guanine
What are the pyrimidines?
Uracil, cytosine, thymine
What are the purines?
Adenine, guanine
What are the three parts of a nucleotide?
Pentose, nitrogen base, phosphate
What is the pentose in DNA?
Deoxyribose
What is the pentose in RNA?
Ribose
What is the chemical formula for a phosphate?
PO4(-3)
What forms the “backbone” of DNA and RNA?
Pentose and phosphate
What are changed during a chemical reaction?
reactants
What are created during a chemical reaction?
Products
What is bond energy?
The amount of energy required to break a bond.
What is added to break bonds?
Energy
When is a chemical reaction at equilibrium?
When reactants and products form at the same rate.
What is activation energy?
The amount of energy that needs to be absorbed to start a chemical reaction.
What is an exothermic reaction?
Reactions that release more energy than they absorb.
What is an endothermic reaction?
Reaction that absorbs more energy than it releases.
What does a catalyst lower?
Activation energy
How do catalysts speed up chemical reactions?
By increasing the activation rate.
Most enzymes are made up of what?
Proteins
Disruptions in what can prevent enzymes from functioning?
Homeostasis
What is a substrate?
A molecule on which an enzyme acts.
What is an active site?
The spot on the enzyme that accepts substrates.
Where are electrons found in an atom?
Electron shell or electron cloud.
When is an atom balanced?
When it has the same number of electrons and protons.
When is an atom “happy”?
When its outer most electron level is full.
What does “therm” mean?
Heat
What does “exo” mean?
Outside
What does “endo” mean?
Within