AP Bio Unit 1 Test

Chapters 2-5

Acid

Substance that lowers the pH of a solution by releasing H+ ions

Anion

A negatively charged ion, forms ionic bonds with cations

Aqueous solution

Solution that can be dissolved in water

Atom

Smallest unit of an element that cannot be broken down into smaller parts

Atomic nucleus

Center of an atom, holds most of the mass, where protons and neutrons are found

Atomic number

Number of protons in nucleus of an atom

Base

A substance that raises the pH by reducing the H+ concentration of a solution

Capillary action

When a liquid “climbs” up a tube, caused by a balance of cohesive and adhesive forces in the liquid

Cation

Positive ion, forms ionic bonds with anions

Compound

Fixed ratio of two or more elements that make up a substance

Dissociation

Molecules break down into ions (water into H3O+ and OH-)

Electron

Negatively charged subatomic particle

Element

Material that cannot be broken down further by chemical reactions

Heat of vaporization

Heat at which a substance turns from a liquid to a gas

Hydration shell

Sphere of water molecules that surround molecules of a solute when dissolved in water

Hydrogen bond

Bond formed between two atoms from two different polar molecules with a partial positive or negative charge

Hydrogen ion

H+, released by acids, lowers the pH of a solution

Hydrophilic

Polar substance with an affinity for water

Hydrophobic

Nonpolar substance that HATES water

Hydrophobic interactions

When nonpolar molecules cluster together instead of dissolving in water, this is due to them disrupting hydrogen bonds and water molecules trying to push them out of the way

Hydroxide ion

OH-, released by bases, raises the pH of a solution

Inorganic

Substances that are not organic, do not contain carbon hydrogen bonds

Ion

At atom of the same element with a different number of electrons, giving it a positive (cation) or negative (anion) charge

Ionic bond

A bond between a cation and an anion where electrons are transferred from one ion to the other

Ionization

The process of an atom becoming an ion by gaining or losing electrons

Isotope

An atom of the same element with a different number of neutrons; radioactive isotopes decay and can be used in the medical field for imaging

Mass number

Number of protons and neutrons in an atom

Matter

Something that takes up space and has mass

Molecular formula

Shows the exact amount of atoms that make up a molecule

Molecule

Two or more atoms bonded with each other

Neutron

Subatomic particle with no charge, contributes to the weight of an atom

Nonpolar covalent bond

Bond where electrons are shared equally because of similar or equal electronegativity in the atoms

Octet rule

Atoms like to fill their outer shells with 8 electrons and will interact with other atoms to do this

Orbital

3D space where an electron can be found most of the time

pH

Measure of how acidic or basic a solution is, relates to the concentration of H+ ions

Polar covalent bond

Bond where electrons are shared but not equally because one atom is more electronegative

Proton

Subatomic particle with a positive charge

Radioactive tracer

When a molecule is replaced with a radioactive isotope so scientists can see the path it took previously (ex. Carbon-14)

Solute

Substance that is dissolved

Solvent

Substance that dissolves other substances

Specific heat

Amount of energy required to change the temperature of 1g of a substance by 1 degree Celsius

Structural formula

A chemical formula that shows the amount of atoms, their arrangement, and their bond structure in a molecule

Surface tension

Makes the surface of water feel like a solid, measures how difficult it is to break the surface of a liquid, due to cohesive forces of polar substances

Valence

Bond capacity of an atom

Valence electrons

Electrons in the outer shell of an atom, can be shared with or transferred to another atom

Ground state

Electrons in this state are closer to the nucleus and have less energy

Excited state

Electrons in this state are further from the nucleus and have more bonding potential. They are also less stable

Mixture

Two or more substances that are physically combined but not chemically bonded

Hydroxyl formula

-OH

Hydroxyl class name

Alcohol

Hydroxyl characteristics

Polar, forms hydrogen bonds with water

Carboxyl formula

-COOH

Carboxyl class name

Carboxylic acid

Carboxyl characteristics

Acts as an acid, polar, hydrophilic

Amino formula

-NH₂

Amino class name

Amine

Amino characteristics

Acts as a base, polar, hydrophilic

Phosphate formula

PO₄^-2

Phosphate class name

Organic phosphate

Phosphate characteristics

Polar, hydrophilic, releases energy when reacting with water

Carbonyl formula

C = O

Carbonyl class name (found at the end)

Aldehyde

Carbonyl class name (found in the middle)

Ketone

Carbonyl characteristics

Associated with sugars, polar, hydrophilic

Methyl formula

-CH₃

Methyl class name

Methylated compound

Methyl characteristics

Nonpolar, affects gene expression, affects shape and function of sex hormones

Sulfhydryl formula

-SH

Sulfhydryl class name

Thiol

Sulfhydryl characteristics

Two react to stabilize protein structures

Carbohydrate elements

CHO

Carbohydrate function

Short term energy storage, structure

Carbohydrate monomer

Monosaccharide

Carbohydrate polymer

Polysaccharide

Carbohydrate examples

Glycogen, glucose, lactose

Carbohydrate functional group

-OH hydroxyl

Lipid elements

CHO

Lipid function

Long term energy storage, insulation and protection, make up cell membranes and hormones

Lipid monomer

Fatty acids

Lipid polymer

Tricylglycerol

Lipid examples

Fats, oils, waxes, steroids, phospholipids

Lipid functional groups

-COOH carboxyl and -OH hydroxyl

Protein elements

CHON(S)

Protein function

enzyme for catalysis, provides structural support, aids in movement and cellular communication

Protein monomer

Amino acids

Protein polymer

Polypeptides

Protein examples

Amylase, pepsin, hemoglobin, keratin, insulin

Protein functional groups

-NH₂ amino, -COOH carboxyl

Nucleic acid elements

CHONP

Nucleic acid monomer

Nucleotides

Nucleic acid polymer

Polynucleotides

Nucleic acid examples

DNA, RNA

Nucleic acid functional groups

PO₄^-2 phosphates

What is this?

Hydroxyl

What is this?

Carboxyl

What is this?

Amino

What is this?

Phosphate

What is this?

Carbonyl (Aldehyde)

What is this?

Carbonyl (Ketone)

What is this?

Methyl