AP Biology Review

Vocabulary flashcards for AP Biology review, covering topics from chemistry of life to animal structure and function.

Element

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

Atom

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

Isotopes

Same element with different amount of neutrons in nucleus; vary in mass.

Compound

Occurs as a result of 2 or more individual elements combining in a fixed ratio; different properties of individual elements; formed by chemical reaction.

Ionic Bond

One or more electrons is transferred from one atom to another, resulting from the attraction of two oppositely charged ions. Typically involves a nonmetal and a metal.

Covalent Bond

Formed when electrons are shared between atoms. Typically involves two nonmetals.

Nonpolar Covalent Bond

Electrons are shared equally.

Polar Covalent Bond

Electrons are shared unequally.

Electronegativity

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

Hydrogen Bond

Hydrogen atom covalently bonds to one electronegative atom is also attracted to another electronegative atom.

Van der Waals Interactions

Attractions between molecules that are close together as a result of “hot spots” of positive or negative charge

Cohesion

Tendency for water to stick to water.

Adhesion

Tendency of water to stick to other substances.

Surface Tension

Results from cohesion of water molecules.

Heat Capacity

Ability of a substance to resist temperature changes.

Heat of Vaporization

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

Solution

A liquid that is a homogenous mix of substances.

Solvent

The dissolving agent of a solution.

Solute

The substance that is dissolved.

Hydrophobic

Substances that do not dissolve in water.

Hydrophilic

Substances that dissolve in water.

Acid

Solution contains a lot of H+.

Base

Solution that contains a lot of OH-.

Organic Compound

Compound that contains carbon.

Inorganic Compound

Compound that does not contain carbon.

Hydrocarbons

Consist of only carbon and hydrogen.

Isomers

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

Polymer

Most macromolecules are chains of building blocks.

Monomer

The individual building blocks of a polymer.

Monosaccharides

Most common are glucose and fructose.

Disaccharides

1 monosaccharide+1 monosaccharide.

Glycosidic Linkage

Bond formed by dehydration synthesis that links monosaccharides to form disaccharides.

Polysaccharides

Repeated units of monosaccharides.

Amino Acid

Monomer of proteins.

Polypeptide

Multiple amino acids bonded by peptide bonds.

Lipids

Consist of carbon, hydrogen and oxygen, but not in a fixed ratio; do not form polymers; little-no affinity for water.

Saturated Fatty Acid

No double bond; carbon chain completely filled (“saturated”) with hydrogen; usually solid at room temp.

Unsaturated Fatty Acid

Double bond along carbon chain, causing a bend; LESS dense, making it liquid at room temperature.

Phospholipids

2 fatty acid “tails” + 1 negatively charged phosphate “head”; amphipathic molecule (molecule that is both polar and nonpolar).

Steroids

Cholesterol; 4-ringed molecule dispersed throughout membrane; maintains membrane stability.

Nucleic Acids

Contain carbon, hydrogen, oxygen, nitrogen, and phosphorous; monomer is nucleotides.

Deoxyribonucleic Acid (DNA)

Sugar=deoxyribose; contains genetic/hereditary information; provides directions for its own replication; directs synthesis of messenger RNA (mRNA), and through mRNA, controls protein synthesis.

Ribonucleic Acid (RNA)

Sugar=ribose; essential for protein synthesis.

Gene

Amino acid sequence of a polypeptide is programmed by a unit of inheritance.

Heterotrophs

living organisms that rely on organic molecules for food; aka consumers.

Autotrophs

Organisms that make their own food; most commonly via photosynthesis; aka producers.

Cell Theory

The cell is life’s basic unit of structure and function.

Prokaryotic Cells

Smaller and simpler than eukaryotic cells, with circular DNA in a nucleoid region and no membrane-bound organelles.

Eukaryotic Cells

More complex cells organized into smaller structures called organelles; DNA in nucleus bounded by a membranous nuclear envelope.

Plasma Membrane

Outer envelope, phospholipid bilayer, regulates movement in/out of cell, semipermeable, fluid-mosaic model.

Fluid-Mosaic Model

Describes the plasma membrane as a mosaic of protein molecules drifting laterally in a fluid bilayer of phospholipids.

Nucleus

Largest organelle of cell; directs what goes on in cell; responsible for cell’s ability to reproduce; home of hereditary information (DNA).

Ribosomes

Sites of protein synthesis; manufacture all proteins required/secreted by the cell; consists of RNA and other proteins.

Endoplasmic Reticulum (ER)

Continuous channel that extends into many regions of the cytoplasm; lipid proteins synthesis/transport.

Golgi Bodies

Process proteins; packaging/distribution centers for materials destined to be sent out of cell; involved in production of lysosomes.

Mitochondria

Responsible for converting the energy from organic molecules into useful energy for the cell; energy molecule in the cell is adenosine triphosphate (ATP).

Lysosomes

Tiny sacs that carry digestive enzymes; break down old/worn out organelles/debris/large ingested particles; cells clean-up crew.

Centrioles

Small. Paired, cylindrical structured often found within microtubule organizing centers (MTOCs); most active during cellular division.

Vacuoles

Fluid-filled sacs that store water/food/wastes/salts/pigments for later use/removal; larger in plant cells.

Cytoskeleton

Network of fibers that maintain cell shape.

Extracellular Matrix

Molecules secreted by cell; mostly glycoproteins or other carb/containing molecules, esp. collagen; provides structure/biochemical support.

Plasmodesmata

Connections between plant cells that allow communication amongst them.

Diffusion

A substance will move down its concentration gradient.

Osmosis

Process where water is diffused.

Isotonic Solution

Solute concentration is the same inside as outside; no net water movement.

Hypertonic Solution

More total dissolved solutes than the cell; cell loses water.

Hypotonic Solution

Less total dissolved solutes than the cell; cell gains water.

Dialysis

Diffusion of solutes across a selectively permeable membrane.

Quorum Sensing

When unicellular organisms make their numbers known to other members of their species.

Taxis

Movement of an organism in response to a stimulus.

Chemotaxis

Movement in response to a certain chemical.

Signal Transduction

The process by which an external signal is transmitted to the inside of a cell.

Apoptosis

Programmed cell suicide; mostly done by caspases (main proteases (enzymes that cut up proteins) that carry out apoptosis).

First Law of Thermodynamics

Energy cannot be created or destroyed. The sum of energy in the universe is constant.

Second Law of Thermodynamics

Energy transfer leads to less and less organization. The universe tends towards entropy.

Exergonic

Products have less energy than the reactants; energy is given off during the reaction.

Endergonic

Require an input of energy; products have more energy than reactants.

Activation Energy

Energy needed to achieve the transition state.

Enzymes

Biological catalysts that speed up reactions.

Substrates

The targeted molecules (reactant).

Active Site

Enzyme brings about transition state by helping the substrate(s) get into position at this location.

Induced Fit

Enzyme slightly changes shape to accommodate the shape of substrates.

Cofactors

Nonprotein helpers of enzymes.

Q10

Measure of sensitivity of a physiological process of enzymatic reaction rate.

Competitive Inhibition

Substance has the exact complementary shape to the active site, it can compete with the substrate and block it from getting into the active site.

Allosteric Inhibitors/Non Competitive Inhibition

Binds to an allosteric site; distorts shape of enzyme so it cannot function until the inhibitor is removed.

Stroma

Inner fluid-filled region of the chloroplast.

Grana

Structures inside stroma that look like stacks of coins.

Thylakoids

Coins of grana. Contain chlorophyll, a light-absorbing pigment that drives photosynthesis.

Photosystem I (PS I)

p700, comprised of a Light harvesting complex, where a photon of light is passed like a wave between pigments and a Reaction center complex, which contains chlorophyll-a and uses light energy to “boost” and electrons and pass onto primary electron acceptor.

Photosystem II (PS II)

P680, comprised of a Light harvesting complex, where a photon of light is passed like a wave between pigments and a Reaction center complex, which contains chlorophyll-a and uses light energy to “boost” and electrons and pass onto primary electron acceptor.

Lytic Cycle

Virus immediately starts using host cell’s machinery to replicate genetic material and create more protein capsids. Virulent phages

Lysogenic

Virus incorporates itself into host genome and remains dormant until it is triggered to switch into the lytic cycle by an environmental signal. Temperate phages

Phagocytes/Macrophages

Engulf antigens.