Chapter 1 - Chemistry of Life Flashcards
what is the level of organization of all living organisms, smallest to largest?
subatomic particles -> atoms -> elements -> molecules -> macromolecules -> cells -> tissues -> organs -> organ systems -> organisms
example of subatomic particles?
p+ (proton), e- (electron), n^0 (neutron)
example of an atom?
oxygen (0)
example of an element?
oxygen (0) ->
example of an molecule?
dioxide (o2)
example of a macromolecule?
lipid, phospholipid
what is an element?
(a pure substance containing only one type of atom)
what is a molecule?
2+ atoms covalently bonded together -> Ex.) oxygen
what is a macromolecule?
a large, carbon-based molecule within a cell (living)
example of a cell?
blood cell, clara cell
where in the level of organization does life begin?
cells
example of tissue?
epithelial tissue
example of organ?
lung
example of an organ system?
respiratory system
example of an organism?
homosapien, panthera leo (lion)
what are the six elements necessary for life? (What is the acronym for these elements?
chonps -> carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur
what is an electron?
an electron is a negatively charged high energy particle with little or no mass. they travel at very high speeds in different energy levels. energy levels are different distances from the nucleus.
(covalent bond def.)
a chemical bond (atoms joined together) between 2+ non-metal atoms (do not have properties of metals). almost all of the substances that make up organisms from lipids to nucleic acids to water, are molecules held together by covalent bonds.
what is a compound?
2 elements bonded together -> ex.) H2O for water and NaCl for sodium chloride
what happens when the ratio of atoms change in a compound?
when the ratio of elements in a compound changes, the physical and chemical properties change too. ex.) H2O vs. H2O2 = water vs. hydrogen peroxide
are molecules compounds? are compounds molecules?
a molecule is a type of compound. all molecules are compounds, but all compounds are not molecules. ex.) molecules = H2O, O2, O3 -> compounds = NaCl, H2O
How does the structure of an atom and it’s subatomic particles look?
Protons and neutrons remain in the nucleus. Rapidly moving electrons form a negatively charged “cloud” around the nucleus.
How are electrons distributed throughout the “cloud”?
Based on differing level of energy and attraction levels called electron shells. Electrons in shells near the nucleus are held more tightly than those shells that are farther than the nucleus.
Why is hydrogen so reactive?
Because 2 electrons can fit in that shell, and hydrogen has room for one more, only having 1 electron.
Do atoms have an electric charge?
Every atom has an equal number of protons and neutrons, which balances it out so an atom has no electric charge.
How do atoms undergo chemical change?
Atoms can undergo chemical change by gaining, losing, or sharing 1 or more electons with other atoms,
What tendency does an atom wil unfilled shells have?
Atoms with unfilled shells have a strong tendency to lose or gain electrons to fill their outer shells.
Do atoms of different elements differ in their number of each subatomic particle?
Atoms of different elements differ in their number of electrons, protons, and neutrons.
Do atoms of the same elements differ in their number of each subatomic particle?
Atoms of the same element have the same number of protons and electrons, but may differ in their number of neutrons.
What are isotopes?
Isotopes are atoms of the same element that differ in their number of neutrons. Ex.) Oxygen-17, an isotope with 8 protons and 9 neutrons.
What is a radioisotope?
Some isotopes have an unstable atomic nuclei that break down, releasing radiation energy. They help determine some to the chemical reactions organisms carry out.
What is used to hold together compounds?
Molecular “glue” is used to hold together compunds. Shared electrons located in the space between the two nuclei are called bonding electrons. The bonded pair is the “glue” that holds the atoms together in molecular units.
What are valence electrons?
Valence electrons are involved in bonding- they are the electrons on the outer most energy level.- Can be gained or lost during a chemical reaction.
When are atoms most stable.
Atoms are most stable when their outer most energy level is filled.
WHat are chemical bonds?
Attraction, sharing, or transferring outer shell electrons from one atom to another.
What are chemical reactions?
Involves the making and breaking of chemical bondsm substances interact and form new bonds and new substances.
What part of an atom is involved during a chemical change?
Only outer shell electrons are involved when atoms react during a chemical change.
What influences does the outer most electrons have?
They react during chemical changes, are a reliable of the reactivity if an atom, but the entire structure if the atom also influences chemical reactions.
What holds atoms together?
Atoms are held together by chemical bonds.
What is the goal of chemical bonds?
To fill the outer electron shell so atoms bond together to get a full outer shell.
What are the 3 main types of bonds?
Ionic bonds, covalent bonds, and hydrogen bonds.
What are covalent bonds?
Covalent bonds are formed when 2 atoms share one or more pairs of electrons, forming molecules. Between two non metals.