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BIOL1P91 Midterm Questions and Correct
Answers
____________ makes up the nucleus of the atom.
A) Protons and electrons
B) Protons and neutrons
C) DNA and RNA
D) Neutrons and electrons
E) DNA only Ans: B) Protons and neutrons
Living organisms are composed of mainly which atoms?
A) Calcium, hydrogen, nitrogen, and oxygen
B) Carbon, hydrogen, nitrogen, and oxygen
C) Hydrogen, nitrogen, oxygen, and helium
D) Carbon, helium, nitrogen, and oxygen
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E) Carbon, calcium, hydrogen, and oxygen Ans: B) Carbon,
hydrogen, nitrogen, and oxygen
The ability of an atom to attract electrons in a bond with another
atom is termed its
A) Hydrophobicity
B) Electronegativity
C) Solubility
D) Valence
E) Both a and b Ans: B) Electronegativity
Hydrogen bonds differ from covalent bonds in that
A) Covalent bonds can form between any type of atoms, and
hydrogen bonds form only between H and O
B) Covalent bonds involve sharing of electrons, and hydrogen
bonds involve the complete transfer of electrons
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C) Covalent bonds result from equal sharing of electrons, but
hydrogen bonds involve unequal sharing of electrons
D) Covalent bonds involve sharing of electrons between atoms, but
hydrogen bonds are the result of weak attractions between a
hydrogen atom of a polar molecule and an electronegative atom of
another polar molecule
E) Covalent bonds are weak bonds that break easily, but hydrogen
bonds are strong links between atoms that are not easily broken
Ans: D) Covalent bonds involve sharing of electrons between
atoms, but hydrogen bonds are the result of weak attractions
between a hydrogen atom of a polar molecule and an
electronegative atom of another polar molecule
A free radical
A) Is a positively charged ion
B) Is an atom with one unpaired electron in its outer shell
C) Is a stable atom that is not bonded to another atom
D) Can cause considerable cellular damage
E) Both b and d Ans: E) Both b and d
© 2025 All rights reserved
BIOL1P91 Midterm Questions and Correct
Answers
____________ makes up the nucleus of the atom.
A) Protons and electrons
B) Protons and neutrons
C) DNA and RNA
D) Neutrons and electrons
E) DNA only Ans: B) Protons and neutrons
Living organisms are composed of mainly which atoms?
A) Calcium, hydrogen, nitrogen, and oxygen
B) Carbon, hydrogen, nitrogen, and oxygen
C) Hydrogen, nitrogen, oxygen, and helium
D) Carbon, helium, nitrogen, and oxygen
© 2025 All rights reserved
, 2 | Page
E) Carbon, calcium, hydrogen, and oxygen Ans: B) Carbon,
hydrogen, nitrogen, and oxygen
The ability of an atom to attract electrons in a bond with another
atom is termed its
A) Hydrophobicity
B) Electronegativity
C) Solubility
D) Valence
E) Both a and b Ans: B) Electronegativity
Hydrogen bonds differ from covalent bonds in that
A) Covalent bonds can form between any type of atoms, and
hydrogen bonds form only between H and O
B) Covalent bonds involve sharing of electrons, and hydrogen
bonds involve the complete transfer of electrons
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, 3 | Page
C) Covalent bonds result from equal sharing of electrons, but
hydrogen bonds involve unequal sharing of electrons
D) Covalent bonds involve sharing of electrons between atoms, but
hydrogen bonds are the result of weak attractions between a
hydrogen atom of a polar molecule and an electronegative atom of
another polar molecule
E) Covalent bonds are weak bonds that break easily, but hydrogen
bonds are strong links between atoms that are not easily broken
Ans: D) Covalent bonds involve sharing of electrons between
atoms, but hydrogen bonds are the result of weak attractions
between a hydrogen atom of a polar molecule and an
electronegative atom of another polar molecule
A free radical
A) Is a positively charged ion
B) Is an atom with one unpaired electron in its outer shell
C) Is a stable atom that is not bonded to another atom
D) Can cause considerable cellular damage
E) Both b and d Ans: E) Both b and d
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