AP Biology Review

Flashcards of AP Biology Review, for test preparation

Element

Substances that cannot be broken down into smaller substances by chemical means.

Four elements that make up 96% mass of living things

Oxygen (O), Carbon (C), Hydrogen (H), and Nitrogen (N).

Atom

Smallest unit of an element and building block of the physical world.

Protons

Positively charged subatomic particles packed with neutrons in the nucleus.

Neutrons

Subatomic particles packed with protons in the nucleus with no charge.

Isotopes

Same element with a different number of neutrons in the nucleus, varying in mass.

Electrons

Negatively charged subatomic particles that spin around the nucleus and differ in their amounts of potential energy.

Valence Electrons

Electrons in the outermost shell, or valence shell, which determine the chemical behavior of an atom.

Atomic Number

Number of protons in the nucleus of an atom.

Mass Number

The sum of protons and neutrons in the nucleus of an atom.

Compound

Substance that occurs as a result of 2 or more individual elements combining in a fixed ratio, formed by a chemical reaction.

Ionic Bond

A bond between a nonmetal and a metal where one or more electrons are transferred from one atom to another, resulting from the attraction of two oppositely charged ions.

Cation

An ion with a positive charge.

Anion

An ion with a negative charge.

Covalent Bond

A bond between a nonmetal and a nonmetal, formed when electrons are shared between atoms.

Nonpolar Covalent Bond

A covalent bond where electrons are shared equally.

Polar Covalent Bond

A covalent bond where electrons are shared unequally.

Electronegativity

An atom's attraction for the electrons in a covalent bond.

Hydrogen Bond

A weak attraction between a hydrogen atom covalently bonded to one electronegative atom and another electronegative atom.

Van der Waals Interactions

Weak attractions that occur when electrons are distributed asymmetrically in molecules or atoms, resulting in "hot spots" of positive or negative charge.

Cohesion

The tendency for water to stick to water.

Adhesion

The tendency of water to stick to other substances.

Surface Tension

Results from the cohesion of water molecules.

High Heat Capacity

The ability of a substance to resist temperature changes.

High Heat of Vaporization

The heat a liquid must absorb for 1g to be converted to gas.

Evaporative Cooling

As a liquid evaporates, its remaining surface cools.

Solution

A liquid that is a homogenous mix of substances.

Solvent

The dissolving agent of a solution.

Solute

The substance that is dissolved.

Aqueous Solution

One where water is the solvent.

Hydrophobic

Substances that do not dissolve in water.

Hydrophilic

Substances that dissolve in water.

Acidic

A solution that contains a lot of H+.

Alkaline

A solution that contains a lot of OH-.

Organic Compound

A compound that contains carbon.

Inorganic Compound

A compound that does not contain carbon.

Hydrocarbons

Consist of only carbon and hydrogen.

Isomers

Compounds with the same molecular formula but different structures/properties.

Functional Groups

The components of organic molecules that are most commonly involved in chemical reactions.

Polymers

Most macromolecules are chains of building blocks.

Monomers

The individual building blocks of a polymer.

Carbohydrates

Contain carbon, hydrogen, and oxygen in a 1:2:1 ratio.

Monosaccharides

Most common are glucose and fructose.

Disaccharides

Formed by dehydration synthesis.

Polysaccharides

Repeated units of monosaccharides.

Proteins

Amino acids are the monomer.

Amino Acids

Monomer of proteins.

Polypeptides

Amino acid + amino acid= dipeptide.

Lipids

Like carbs, consist of carbon, hydrogen and oxygen, but not in a fixed ratio.

Saturated Fatty Acid

No double bond.

Unsaturated Fatty Acid

Double bond along carbon chain, causing a bend.

Phospholipids

2 fatty acid “tails” + 1 negatively charged phosphate “head.”

Steroids

Cholesterol.

Nucleic Acids

Contain carbon, hydrogen, oxygen, nitrogen, and phosphorous.

Origins of the Earth

Alexander Oparin and J. B. S. Haldane proposed that the primitive atmosphere contained the following gases: Methane (CH4), Ammonia (NH3), Hydrogen (H2), Water (H2O).

Autotrophs

Organisms that make their own food.

Living things

All living things are composed of cells.

Prokaryotic cells

Only in domains Bacteria and Archaea.

Eukaryotic cells

More complex.

Organelles

Each organelle has its own special task.

Plasma Membrane

Outer envelope.

Fluid-mosaic model

Peripheral proteins are loosely associated with the lipid bilayer.

Adhesion proteins

Membrane proteins form junctions between adjacent cells.

Receptor proteins

Serve as docking sites for arrivals at the cell.

Transport proteins

Form pumps that use ATP to actively transport solutes across the membrane.

Cell surface marker

Exposed on cellular surface.

Cholesterol

Maintain fluidity.

Nucleus

Largest organelle of the cell.

Ribosomes

Sites of protein synthesis.

Endoplasmic Reticulum (ER)

Continuous channel that extends into many regions of the cytoplasm.

Rough ER

Attached to nucleus.

Smooth ER

Lacks ribosomes.

Golgi Bodies

Process proteins.

Mitochondria

“PoWeRhOUsE oF ThE cElL”.

Cristae

Separates innermost area (called the matrix) from the intermembrane space.

Lysosomes

Tiny sacs that carry digestive enzymes.

Centrioles

Small. Paired, cylindrical structured often found within microtubule organizing centers (MTOCs).

Vacuoles

Latin for “empty cavity.”

Peroxisomes

Breakdown of long fatty acids through beta-oxidation.

Cytoskeleton

Network of fibers that maintain cell shape.

Microtubules

Made up of protein tubulin.

Microfilaments

Important for movement.

Cilia and Flagella

Allow motion in single-celled organisms.

Extracellular matrix

Molecules secreted by cell.

Plant have plasmodesmata

Connections between plant cells that allow communication amongst them.

Plant cells have cell wall

Rigid layer of cellulose.

Plant cells have chloroplast

Contain chlorophyll, making them green.

(Ψ) Water potential

The measure of potential energy in water and describes the eagerness of water to flow from an area of high water potential to an area of low water potential.