Studied by 0 peopleMatter definition
Anything that occupies space
What is chemistry?
the scientific study of matter and the interactions of matter
What is composed of matter?
the physical universe (living and nonliving)
What are elements?
substances that cannot be broken down into simpler substances by ordinary chemical means
How many out of 118 known elements are “naturally occurring”?
92
How many elements are involved in maintaining life?
24
What’s group 1’s name?
alkali metals except hydrogen
What’s group 2’s name?
alkali earth metals
What’s group blue’s name?
transitional metals
What’s group 7’s name?
halogens
What’s group 0’s name?
noble gases
What group does carbon, nitrogen, oxygen, phosphorus, sulfur, and selenium belong to?
nonmetals
What group does boron, silicon, geranium, arsenic, antimony, tellurium, and polonium belong to?
metalloid
What does aluminum, gallium, indium, tin, thallium, lead, bismuth, ununtrium, flerovium, ununpentium, livermorium belong to?
basic metals
What group does the top green period belong to?
lanthanide
What group does the bottom green period belong to?
Actinide
What are the elements important to physiology?
C, N, O, F, S, O, H, Ca, P
Approximately, 96% is composed of the human body?
oxygen, carbon, hydrogen, and nitrogen
Atom definition
the smallest unit of an element.
What is a proton?
a positively charged particle in an atomic nucleus
What is a neutron?
a noncharged particle in an atomic nucleus.
What is an electron?
a negatively charged particle that revolves around an atomic nucleus
What is a nucleus comprised of ?
protons and neutrons
What are electron shells?
where electrons orbit, or revolve around, the nucleus at high speeds that are located at various distances from the nucleus
What are valence shells?
an atom’s outermost shell of electrons
The overall electrical charge of an atom is _______.
neutral
The number of protons = the number of ________.
electrons
Most neutral atoms are ________
unstable
How do atoms gain stability?
lose, gain, or share electrons
Atomic number definition.
the number of protons (the number of electrons)
Chemical symbol definition.
a shorthand for referring to an element or atom of an element
Atomic mass definition.
the sum of the number of protons and neutrons
What are isotopes?
Atoms of the same element with different numbers of neutrons
What are radioisotopes?
certain isotopes of some elements have an unstable nucleus that emits high-energy radiation as it breaks down to form a more stable nucleus
Molecule definition.
a substance formed by two or more atoms bonded together by covalent bonds only
A molecule can have what atoms?
identical or different
Compound definition
a substance formed by the atoms from two or more elements
What bonds are in a compound?
ionic and covalent
What is a chemical formula?
expresses the chemical composition of a substance
Molecular formula definition.
expresses the composition of the molecule or compound using chemical symbols and numbers but it does not describe how the atoms are arranged
Structural formula definition
is a diagram that indicates the composition and number of atoms but also shows how the atoms are linked to each other
Chemical bond definition
a force of attraction between two atoms
Ionic bond formation.
is the formation of 2 ions with opposing charges; cation (+) and an anion (-) that creates a force bond and an ionic compound
What are covalent bonds?
atoms that form molecules by sharing electrons
What are nonpolar covalent bonds?
they are shared electrons that spend equal time revolving between the two atoms
A characteristic of a nonpolar covalent bond?
are hydrophobic
What are polar covalent bonds?
they are an unequal sharing of electrons between the two atoms
What are characteristics of a polar covalent bond?
One atom has greater electronegativity
are hydrophilic
What is a hydrogen bond?
weak attractive force between slightly positive and a slightly negative areas
How does a hydrogen bond occur?
occur within the same molecule, between different molecules, and between polar molecules and ions
What is a chemical reaction?
bonds between atoms are formed or broken
Synthesis (anabolic) reaction definition
the combining of smaller molecules to form more complex molecules
Decomposition (catabolic) reaction definition
the breakdown of complex molecules into simpler molecules.
Exchange (rearrangement) reaction
a reaction in which two reactants exchange components to form two different products.
Reversible reaction definition
the reactants and products may convert in both directions
Inorganic substances definition
contain carbon or hydrogen but not both
Organic substances definition
always contain both carbon and hydrogen, usually oxygen as well
What is a major inorganic substance?
water
What are some facts about water?
composes approximately 2/3 of body weight
occurs in the body as part of an aqueous solution
the solvent for electrically charged solutes
serves as a site for chemical reactions
used for transport of solutes
serves as a lubricant
aids in maintaining a constant body temperature
serves as a reactant in the breakdown (hydrolysis) of organic molecules
What are water compartments?
specific locations where water is found in the body
Intracellular fluid (ICF) definition
fluid within cells; about 65% of the total body water
Extracellular fluid (ECF) definition
all fluid not in cells; about 35% of the total body water
Interstitial fluid (tissue fluid) definition
fluid in spaces between cells
Plasma definition
fluid portion of blood
Lymph definition
fluid in lymphatic vessels
Transcellular fluids definition
fluid in more limited locations/ more specific locations
What are electrolytes?
Ionic compounds ionize (dissociate) in water, releasing ions
Nonelectrolytes definition
do not ionize when they dissolve in water and are usually organic compounds
Acid definition
increases H+ concentration in solution and releases H+ ions (protons)
Base definition
decreases the H+ concentration in a solution
What is pH?
a measure of the H+ concentration in a solution
What is a pH scale?
indicates the measure of acidity or alkalinity of a solution
What is a buffer?
Maintain normal pH of body fluids because slight pH changes can be harmful to body cells
Chemical or chemicals that either picks up or releases H+ to keep a solution’s pH constant
What are salts?
are ionic compounds that ionize in water but do not produce H+ and OH-
What is the dehydration synthesis?
removes water to join molecules
What is hydrolysis?
adds water to break apart molecules
What are carbohydrates?
an organic molecule composed of carbon, hydrogen, and oxygen in a 1:2:1 ratio.
Carbohydrates are what to the body?
the primary source of nutrient energy for cells of the body
What are monosaccharides?
a simple sugar; a structural unit of carbohydrates.
What is glucose?
the monosaccharide that is the primary energy source for cells
Disaccharide definition
a molecule composed of two monosaccharides chemically combined
Polysaccharide definition
an organic macromolecule formed of many monosaccharide units
What are fructose and galactose?
isomers of glucose
What is an isomer?
molecules with the same molecular formula but different structures
Where are pentose sugars found in?
DNA nad RNA
What is maltose?
aka malt sugar; glucose + glucose
What is sucrose?
aka table sugar, glucose + fructose
What is lactose?
aka dairy sugar; glucose + galactose
What is glycogen?
the polysaccharide that is the storage form for carbohydrates in the body for animals
Starch definition
plant carbohydrate storage
a common polysaccharide in foods derived from plants
What are lipids?
a class of organic macromolecules that includes steroids, triglycerides, and phospholipids
diverse group composed of carbon, hydrogen, and oxygen atoms
What are triglycerides?
a lipid molecule composed of three fatty acids attached to glycerol; a fat molecule.
What are phospholipids?
a molecule containing two fatty acids and a phosphate group attached to glycerol
What are steroids?
a group of lipids that includes sex hormones and cholesterol.
What forms triglycerides?
Formed of one glycerol molecule and three fatty acid molecules
What is glycerol?
an organic molecule that is the backbone of triglyceride and phospholipid molecules.
What is a fatty acid?
an organic molecule that forms part of a triglyceride
Triglycerides are nonpolar molecules, meaning that they are ______
hydrophobic
What are triglycerides classified as?
saturated or unsaturated fats
Where are triglycerides found in?
adipose tissue around internal organs and beneath the skin
Note
Flashcard