Unit 1 vocab words ap bio

Matter

Anything that takes up space and has mass

Elements

Pure substances that cannot be broken down further

Atoms

Smallest unit of matter that still has properties of an element

Compounds

Substances formed by two or more different elements

Proton

Positively charged particle in the nucleus

Electron

Negatively charged particle orbiting the nucleus

Atomic number

Number of protons in an atom

Covalent bonds

Bonds formed when atoms share electrons

Ionic bond

Bond formed when electrons are transferred between atoms

Hydrogen bonds

Weak bonds between polar molecules involving hydrogen

Molecules

Two or more atoms held together by bonds

Polarity

Unequal sharing of electrons causing partial charges

Cohesion

Water molecules stick to each other

Adhesion

Water molecules stick to other surfaces

Specific heat

Amount of energy needed to change temperature of a substance

Density of ice

Ice is less dense than liquid water

Reactants

Substances that start a chemical reaction

Products

Substances made in a chemical reaction

Photosynthesis

Process plants use to convert light energy into chemical energy

Cellular respiration

Process cells use to break down glucose for energy

Hydrophilic

Attracted to water

Hydrophobic

Repelled by water

Acid

Substance that increases hydrogen ion concentration

Base

Substance that decreases hydrogen ion concentration

pH scale

Scale that measures how acidic or basic a solution is

Good solvent

Water dissolves many substances well

Lower density as a solid

Ice floats because solid water is less dense than liquid water

High heat of vaporization

Water absorbs lots of energy before evaporating

Capillary action

Movement of water up narrow tubes due to cohesion and adhesion

Meniscus

Curve of liquid in a container caused by adhesion

Solvents

Substances that dissolve other substances

Solutes

Substances that get dissolved

Biological macromolecules

Large molecules essential for life (carbs, lipids, proteins, nucleic acids)

Monomers

Building blocks of macromolecules

Dehydration synthesis

Reaction that joins monomers by removing water

Hydrolysis

Reaction that breaks polymers by adding water

Carbohydrate

Molecule made of sugars used for energy and structure

Monosaccharide

Simple sugar (glucose, fructose)

Disaccharide

Two sugars joined together

Glycosidic bond

Bond that links monosaccharides

Polysaccharide

Long chain of sugars (starch, glycogen, cellulose)

Starch

Energy storage in plants

Glycogen

Energy storage in animals

Cellulose

Structural component of plant cell walls

Chitin

Structural component in fungi cell walls and exoskeletons

Non-polar

Molecules with no charge distribution

Polar

Molecules with uneven charge distribution

Hydrocarbons

Molecules made of hydrogen and carbon

Isomers

Molecules with same formula but different structures

Stereoisomers

Isomers arranged differently in 3D space

Enantiomers

Mirror-image isomers

Macromolecules

Large organic molecules built from smaller units

Polymers

Large molecules made of repeating monomers

Enzymes

Proteins that speed up chemical reactions

Carbon bonding

Carbon can form 4 covalent bonds, allowing complex molecules

Lipids

Fats and oils that store energy and make cell membranes

Triacylglycerols

Another name for triglycerides (fats)

Triglycerides

Lipids made of glycerol and 3 fatty acids

Saturated fatty acids

Fatty acids with no double bonds (solid at room temp)

Unsaturated fatty acids

Fatty acids with double bonds (liquid at room temp)

Trans fat

Unsaturated fat with trans double bonds (unhealthy)

Omega

Type of polyunsaturated fatty acid

Wax

Lipid made of long fatty acid and alcohol chain

Phospholipids

Lipids that make up cell membranes (polar head, nonpolar tails)

Steroids

Lipids with 4 carbon rings

Cholesterol

Steroid important in membranes and precursor to hormones

Dipeptide

Two amino acids linked by a peptide bond

Polypeptide

Chain of many amino acids

Hormones

Chemical messengers that regulate body processes

Protein denaturation

Loss of protein shape due to heat or pH

Peptide bond

Bond linking amino acids

Primary structure

Sequence of amino acids in a protein

Secondary structure

Folding into alpha helices or beta sheets

Tertiary structure

Overall 3D shape of a protein

Quaternary structure

Protein structure with multiple polypeptides

Chaperones (chaperonins)

Proteins that help other proteins fold correctly

DNA

Molecule storing genetic information

RNA

Molecule involved in protein synthesis

Nucleic acids

Polymers of nucleotides (DNA and RNA)

Nucleotides

Building blocks of nucleic acids

Polynucleotides

Long chains of nucleotides

Purines

Double-ring bases (adenine, guanine)

Pyrimidines

Single-ring bases (cytosine, thymine, uracil)

Phosphodiester

Bond linking nucleotides in nucleic acids

Transcription

Process of making RNA from DNA

Translation

Process of making proteins from mRNA