Bio 101 NVCC Exam 1 Questions and
Verified Detailed Answers | Latest
Update
Matter - ✔✔organisms are composed of matter
Element - ✔✔- A substance that cannot be broken down to other substances by
chemical reactions
- Oxygen, carbon, and hydrogen make up 96.3% of the body
- An element's properties depend on the structure of its atoms
Compound - ✔✔A substance consisting of two or more elements in a fixed ratio
Trace elements - ✔✔required by an organism in only minute quantities
Atoms - ✔✔the smallest unit of matter that still contains properties of an
element
Protons - ✔✔- Positively charged particles
- The negative and positive protons hold the atom together
- # of protons = # of neutrons = # of electrons
Neutrons - ✔✔the particles of the nucleus that have no charge
Electrons - ✔✔Negatively charged particles
atomic number - ✔✔the number of protons in an atom
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,mass number - ✔✔the sum of the number of neutrons and protons in an atomic
nucleus
Isotopes - ✔✔- Atoms of the same element that have different numbers of
neutrons
- Used for dating fossils, tracking atoms through metabolic processes, and
diagnosing medical disorders
radioactive isotope - ✔✔An isotope whose nucleus decays spontaneously,
giving off particles and energy.
electron shells (energy levels) - ✔✔- First shell: 2 electrons
- Second shell: 8 electrons
- Third shell: 8 electrons
- energy levels of shells increase with distance from the nucleus
valence shell - ✔✔The outermost energy shell of an atom, containing the
valence electrons involved in the chemical reactions of that atom.
valence electrons - ✔✔Electrons on the outermost energy level of an atom
covalent bond - ✔✔- A chemical bond that involves sharing a pair of electrons
between atoms in a molecule
- shared electrons count as part of each atom's valence shell
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, - 2 or more atoms held together by covalent bonds constitute a molecule
Molecule - ✔✔two or more atoms held together by covalent bonds
single bond, double bond, triple bond - ✔✔a bond form when two atoms share
one/two/three pairs of electrons
Electronegativity - ✔✔an atom's attraction for the electrons in a covalent bond
nonpolar covalent bond - ✔✔a covalent bond in which the electrons are shared
equally by the two atoms
polar covalent bond - ✔✔A covalent bond in which electrons are not shared
equally
ionic bond - ✔✔Formed when one or more electrons are transferred from one
atom to another
ions - ✔✔positively and negatively charged atoms
Cation - ✔✔A positively charged ion
Anion - ✔✔A negatively charged ion
salt - ✔✔- an ionic compound made from the neutralization of an acid with a
base.
- found in nature as crystals
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©KERRYMARTIN 2025/2026. YEAR PUBLISHED 2025.
Verified Detailed Answers | Latest
Update
Matter - ✔✔organisms are composed of matter
Element - ✔✔- A substance that cannot be broken down to other substances by
chemical reactions
- Oxygen, carbon, and hydrogen make up 96.3% of the body
- An element's properties depend on the structure of its atoms
Compound - ✔✔A substance consisting of two or more elements in a fixed ratio
Trace elements - ✔✔required by an organism in only minute quantities
Atoms - ✔✔the smallest unit of matter that still contains properties of an
element
Protons - ✔✔- Positively charged particles
- The negative and positive protons hold the atom together
- # of protons = # of neutrons = # of electrons
Neutrons - ✔✔the particles of the nucleus that have no charge
Electrons - ✔✔Negatively charged particles
atomic number - ✔✔the number of protons in an atom
1|Page
©KERRYMARTIN 2025/2026. YEAR PUBLISHED 2025.
,mass number - ✔✔the sum of the number of neutrons and protons in an atomic
nucleus
Isotopes - ✔✔- Atoms of the same element that have different numbers of
neutrons
- Used for dating fossils, tracking atoms through metabolic processes, and
diagnosing medical disorders
radioactive isotope - ✔✔An isotope whose nucleus decays spontaneously,
giving off particles and energy.
electron shells (energy levels) - ✔✔- First shell: 2 electrons
- Second shell: 8 electrons
- Third shell: 8 electrons
- energy levels of shells increase with distance from the nucleus
valence shell - ✔✔The outermost energy shell of an atom, containing the
valence electrons involved in the chemical reactions of that atom.
valence electrons - ✔✔Electrons on the outermost energy level of an atom
covalent bond - ✔✔- A chemical bond that involves sharing a pair of electrons
between atoms in a molecule
- shared electrons count as part of each atom's valence shell
2|Page
©KERRYMARTIN 2025/2026. YEAR PUBLISHED 2025.
, - 2 or more atoms held together by covalent bonds constitute a molecule
Molecule - ✔✔two or more atoms held together by covalent bonds
single bond, double bond, triple bond - ✔✔a bond form when two atoms share
one/two/three pairs of electrons
Electronegativity - ✔✔an atom's attraction for the electrons in a covalent bond
nonpolar covalent bond - ✔✔a covalent bond in which the electrons are shared
equally by the two atoms
polar covalent bond - ✔✔A covalent bond in which electrons are not shared
equally
ionic bond - ✔✔Formed when one or more electrons are transferred from one
atom to another
ions - ✔✔positively and negatively charged atoms
Cation - ✔✔A positively charged ion
Anion - ✔✔A negatively charged ion
salt - ✔✔- an ionic compound made from the neutralization of an acid with a
base.
- found in nature as crystals
3|Page
©KERRYMARTIN 2025/2026. YEAR PUBLISHED 2025.
