APHY 101: CH 2- Overview

bio-

life

di-

two

glyc-

sweet

iso-

equal

lip-

fat

-lyt

break down

mono-

one

poly-

many

sacchar-

sugar

syn-

together

matter

anything that has weight and occupies space

it can exist as solids, liquids, and gases

mass

the amount of matter present

weight

how “heavy” something is as a result of the gravitational pull on mass

chemistry

the science of the composition and interactions of matter

studies the composition, properties, and interactions of matter

atom

smallest particle of an element that has the properties of that element

electron

extremely small particle within an atom

almost no weight

carries a negative electrical charge

proton

relatively large particle within an atom

carries a positive electrical charge and is found within an atomic nucleus

neutron

relatively large particle within an atom

uncharged and electrically neutral

found within the atomic nucleus

ion

particle that is electrically charged because it has gained or lost one or more electrons

molecule

particle formed by the chemical union of two or more atoms

biochemistry

branch of science dealing with the chemistry of living organisms

elements

any of the fundamental chemical substances, each characterized by a distinct type of atom

compound

substance composed of two or more chemically bonded elements

bulk elements

basic chemicals required in abundance

these elements make up more than 95% of the human body

what are the elements that the body requires in large amount?

carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorous

trace elements

basic chemical substance needed in small quantity

are important parts of enzymes, which are compounds that regulate the rates of chemical reactions in organisms

ultratrace elements

basic chemical substances needed in very small quantity

chemical bonds

attractive forces that can hold atoms together

atomic number

number of protons in the atoms of a particular element

mass number

the number of protons plus neutrons in an atom’s nucleus

two ways that atoms may combine with other atoms

-ionic bonds → oppositely charged ions attract each other

-covalent bonds → atoms sharing electrons

molecular formula

shows the types of atoms in a particular molecule, and the number of each type of atom

structural formula

shows the arrangement of atoms within a molecule, and uses lines to represent pairs of shared electrons

polar molecule

has equal number of protons and electrons so there is no net charge

has one slightly negative end and one slightly positive end

reactanst

starting material changed by the chemical reaction

products

the atoms, ions, or molecules formed at the reaction’s conclusion

synthesis

building large molecules by bonding smaller ones

decomposition

the breakdown of molecules

ex: AB → A + B

reversible reaction

chemical reaction in which the products can react, yielding the original reactants

ex: A + B <=> AB

catalysts

molecules that influence the rates of chemical reactions but are not consumed in the process

exchange reaction (replacement reaction)

chemical reaction in which parts of two types of molecules trade positions

ex: AB + CD → AD + CB

what are the two general types of chemicals?

organic and inorganic

organic

have carbon and hydrogen

inorganic

all other chemicals that are not carbon or hydrogen

why do many organic molecules have long chains or ring structures?

because of a carbon’s ability to form four covalent bonds

electrolytes

substance that ionizes in a water solution

usually inorganic substances

nonelectrolytes

substance that does not dissociate into ions when dissolved in water

usually organic compounds

what are some common inorganic substances?

water, oxygen, carbon dioxide, and inorganic salts

a major component of blood and other body fluids, including fluids in cells

water

solvent

a substance in which other substances dissolve

ex: water

solute

a substance dissolved in a solvent, such as water

solution

the combination of a solvent and any solutes dissolved in it

most metabolic reactions occur in ___

water

water balance

when the volume of water entering and produced by the body is equal to the volume leaving it

what is carbon dioxide in the body?

a waste product

electrolyte balance

condition when the quantities of electrolytes entering the body equal those leaving it

4 macromolecules of the body

proteins, lipids, carbohydrates, nucleic acids

carbohydrates

provide much of the energy that cells require

supply materials to build certain cell structures and are stored as reserve energy supplies

2 types of simple carbohydrate

monosaccharides and disaccharides

monosaccharide

may include three to seven carbon atoms in a straight chain or ring

includes five carbon sugar ribose and deoxyribose

includes the six carbon sugars, glucose, dextrose, fructose, and galactose

2 types of disaccharides

sucrose and lactose

each consists of two simple sugar building blocks

complex carbohydrates are also called…

polysaccharides

polysaccharides

built of simple carbohydrates linked to form larger molecules of different sizes

what is a polysaccharide abundant in plant

cellulose

which polysaccharide can humans not digest?

cellulose

what polysaccharide can humans digest?

starch or plant starch

what polysaccharide can humans synthesize?

glycogen

lipids

a group of organic chemicals that are insoluble in water but soluble in organic solvents like ether and acetone

what are the compounds of lipids?

fats, phospholipids, and steroids

what is the most abundant lipid?

triglycerides

triglycerides

lipid composed of three fatty acids and a glycerol molecule; fat

what are triglyceride molecules composed of?

fatty acids and glycerol

saturated fatty acid

fatty acid where single carbon-carbon bonds link all the carbon atoms

unsaturated fatty acid

has one or more double bonds between carbon atoms

monounsaturated fatty acids

fatty acids with one double bond

polyunsaturated fatty acids

two or more double bonds

dietary triglycerides

referred to as fats

saturated triglycerides (saturated fats)

abundant in fatty foods that are solids at room temperature

ex: butter, lard, and most animal fats

unsaturated glycerides (unsaturated fats)

are in foods that are liquid at room temperature

ex: soft margarine, olive oil, and seed oils(corn, grape, sesame, soybean, peanut, etc)

which oils are unusual in that they are high in saturated fats but are liquids at room temperature?

coconut and palm kernel oils

What are the most heart-healthy fats?

olive and canola(rapeseed) oil

these oils are monosaturated

hydrogenation

produces fats that are partially unsaturated and also trans

process of adding hydrogen atoms to certain vegetable oils to make them harder and easier to use

phospholipid molecule

has only two fatty acid chains and has a portion containing a phosphate group

the phosphate part is soluble in water (hydrophilic) and forms the “head” of the molecule

the fatty acid portion is insoluble in water (hydrophobic) and forms a “tail”

the fact that phospholipids are both attracted to and repelled by water allows them to form __

biological membrances

steroid molecules

are complex structure that include connected rings of carbon atoms

has four connected rings of atoms

the three more important steroids

cholesterol, sex hormones, and hormones from the adrenal gland

cholesterol

found in all body cells and used to synthesize other steroids

sex hormones

estrogen, progesterone, and testosterone

proteins

nitrogen containing organic compounds composed of many bonded amino acid molecules

enzymes

protein that catalyzes a specific biochemical reaction

what are the building blocks of protein?

amino acids

amino acids

organic compound that includes an amino group and a carboxyl group

peptide bonds

covalent bonds that link the amino end of one amino acid with the carboxyl end of another

what are the four levels of structure in a protein?

primary, secondary, tertiary, and quaternary structures

primary structure

the amino acid sequence

the order in which particular amino acids occur in the polypeptide chain

secondary structure

the polypeptide chain either forms a springlike coil (alpha helix) or folds back and forth on itself (beta-pleated sheet)

arises from hydrogen bonding

motifs

general shapes that arise from secondary structures

tertiary structure

hydrogen bonding and covalent bonding between atoms in different and distant parts of a polypeptide imparting another larger level of folding

points of attachment is farther apart along the amino acid sequence than it is in a secondary structure

what can denature proteins

high temperatures, radiation, pH changes, and certain chemicals like urea

quaternary structure

several polypeptide chains that are connected in a fourth level to form a very large molecule

ex: hemoglobin is a quaternary protein made up of four separate polypeptide chains