BIOL 100 - CH2

the branch of science concerned with the composition and properties of material substances, including their abilities to change into other substances

Anything that takes up space and has mass. All forms are made up of atoms

units of matter that cannot be broken down into simpler substances by ordinary chemical means

a "pure" form of matter containing only one kind of atom

atoms that have the same number of protons but differ in the number of neutrons

unstable, radiation-emitting isotopes

about 60 occur naturally

molecule that contains 2 or more different elements

a chemical bond formed when outer shell electrons are shared between atoms

a chemical structure composed of atoms held together by covalent bonds

an atom or group of atoms that carries an electric charge resulting from the loss or gain of electrons

a chemical bond that results from the mutual attraction of oppositely charged ions

a weak chemical bond formed between a partially positively charged hydrogen atom in a molecule and a partially negatively charged atom in another molecule or in another region of the same molecle

any substance that inreases the concentration of hydrogen ions in solution

any substance that reduces the concentration of hydrogen ions in solution

a measure of hydrogen ion concentration of a solution; values range from 1-14

a scale for measuring the concentration of hydrogen ions.

Ranges from 0-14

• pH of 7 is neutral
• pH <7 is acidic
• pH >7 is basic

a substance that prevents dramatic changes in pH by removing excess hydrogen ions from solution when concentrations increase and adding hydrogen ions when concentrations decrease.

a giant molecule of life such as a nucleic acid, protein, or polysacchride. formed by the joining together of smaller molecules

a large molecule formed by the joining together of many smaller molecules of the same general type (monomers)

a small molecule that joins with identical molecules to form a polymer

the process by which polymers are formed. Monomers are linked together through the removal of a water molecule

the process by which polymers are broken apart by the addition of water

an organic molecule that provides fuel for the human body (sugars and starches). can be classified by size into the monosaccharides, disaccharides, and polysaccharides

the smallest molecular unit of a carbohydrate.

known as simple sugars

a chain of a few monosaccharides (simple sugars) that are joined together by dehydration synthesis.

Disaccharides, formed by the joining of 2 monosaccharides, are an example

a molecule formed when 2 monosaccharides covalently bond to each other through dehydration synthesis.

Known as a double sugar

a complex carbohydrate formed when large numbers of monosaccharides (most commonly Glucose) join together to form a long chain through dehydration synthesis.

Most store energy or provide structure

the storage polysaccharide in plants

the storage polysaccharide of animals

this complex carbohydrate is stored in the liver and muscles where it serves as a short-term energy source that can be broken down to release energy-packed glucose molecules

a structural polysaccharide found in plants.

humans lack the enzymes to break this down, and thus it passes unchanged through our digestive tract.

has no nutritional value as a nutrient, however is an important form of dietary fiber

a compound (i.e. triglyceride, phospholipid, steroid) that doesn't dissolve in water.

the lipids composed of one molecule of glycerol and 3 fatty acids.

known as fats when solid and oils when liquid

chains of carbon atoms bonded to hydrogens with an acidic group (COOH) at one end.

3 bond to a molecule of glycerol to form a triglyceride (fat)

an important component of cell membranes.

it has a nonpolar "water-fearing" tail (made up of fatty acids) and a polar "water-loving" head (containing an R group, glycerol, and phosphate)

water-fearing

[i.e. the tails of phospholipids (components of the plasma membrane)]

water-loving

[i.e. the heads of phospholipids (components of the plasma membrane)]

a lipid, such as cholesterol, consisting of 4 carbon rings with functional groups attatched

the macromolecules composed of amino acids linked by peptide bonds.

functions include structural support, transport, movement, and reguation of chemical reactions

the bulding blocks of proteins consisting of a central carbon atom bound to a hydrogen atom, an amino group (NH₂), a carboxyl group (COOH), and a side chain designated by the letter R.

20 are important to human life

some can be synthesized by our bodies (nonessential), where as others cannot be synthesized & must be obtained through food we eat (essential)

a chain containing only a few amino acids

a chain containing 10 or more amino acids

the precise sequence of amino acids of a protein. this sequence, determined by the genes, dictates a protein's structure and function

the bending and folding of the chain of amino acids of a protein to produce shapes (i.e. coils, spirals, and pleated sheets). these shapes form as a result of hydrogen bonding between different parts of the polypeptide chain.

the 3-dimensional shape of proteins formed by hydrogen, ionic, and covalent bonds between different side chains

the process by which changes in the environment of a protein, such as increased heat or changes in pH, cause it to unravel and lose its 3-dimentional shape. change in the shape of a protein results in loss of function

the shape of an aggregate protein.

determined by the mutually attractive forces between the protein's subunits

a substance (usually a protein, but sometimes an RNA molecule) that speeds up chemical reactions without being consumed in the process

a specific locattion on an enzyme where the substrate binds

complex formed when a substrate binds to an enzyme at the active site

the molecular basis of genetic inheritance in all cells and some viruses.

a category of nucleic acids that usualy consists of a double helix and two strands. the sequence of nucleotides carries the instructions for assembling proteins

a single-stranded nucleic acid that contains ribose (a 5-carbon sugar), phosphate, adenine, uracil, cytosine, or guanine.

plays a variety of roles in protein synthesis

a subunit of DNA composed of one 5-carbon sugar (either ribose or deoxyribose), one phosphate group, and one of the 5 nitrogen-containing bases.

building blocks of of nucleic acids (DNA/RNA)

a nucleotide that consists of the sugar ribose, the base adenine, and 3 phosphate groups.

the energy currency of all living cells

the number of protons in an atom's nucleus

sum of the number of protons plus the number of neutrons in an atom

energy moving through space (i.e. radio waves, light, heat, and the excess energy/particles given off by unstable isotopes as they break down)