1
UCI BIO 93 MIDTERM 1 ACTUAL
2025/2026 QUESTIONS AND 100%
CORRECT ANSWERS
smallest unit of chemical elements - (ANSWER)atoms
two or more atoms combined - (ANSWER)molecules
two or more elements combined in a fixed ration - (ANSWER)compound
... are 4 elements that make up 96% of all living matter - (ANSWER)C, O, H, N
what is the strongest bond? - (ANSWER)covalent bond
sharing of electrons by two atoms - (ANSWER)covalent
transfer of electrons between two atoms - (ANSWER)ionic
what is a weak bond? - (ANSWER)hydrogen bond
the H atom forms one covalent bond and a second weaker bond with an atom in
another molecules - (ANSWER)hydrogen bond
,2
equal sharing of electrons
(two of the same element) - (ANSWER)nonpolar
unequal sharing of electrons
has a charge
(water) - (ANSWER)polar
what is the charge of O in water? - (ANSWER)negative
what is the charge of H in water? - (ANSWER)positive
interactions between water molecules
(H2O with H2O) - (ANSWER)cohesion
interactions between water and other molecules - (ANSWER)solvent
what is the maximum amount of bonds that hydrogen can form? - (ANSWER)4
bonds
in room temperature of water what % is the maximum amount of bonds going to
be made? - (ANSWER)15%
, 3
when H+ concentration increases... - (ANSWER)more acidic
what H- concentration decreases... - (ANSWER)more basic
affinity for water
(polar and ionic bonds) - (ANSWER)hydrophilic
repel water
(nonpolar covalent bonds) - (ANSWER)hydrophobic
chemical processes are sensitive to pH changes and resist change in the pH
solution - (ANSWER)buffers
the pH of human blood is... - (ANSWER)7.4
what are the main buffers in blood? - (ANSWER)carbonic acid and bicarbonate
response to a rise in pH in blood (becomes more basic) - (ANSWER)right
response to a drop in pH in blood (becomes more acidic) - (ANSWER)left
building blocks for biological molecules - (ANSWER)carbon atoms
UCI BIO 93 MIDTERM 1 ACTUAL
2025/2026 QUESTIONS AND 100%
CORRECT ANSWERS
smallest unit of chemical elements - (ANSWER)atoms
two or more atoms combined - (ANSWER)molecules
two or more elements combined in a fixed ration - (ANSWER)compound
... are 4 elements that make up 96% of all living matter - (ANSWER)C, O, H, N
what is the strongest bond? - (ANSWER)covalent bond
sharing of electrons by two atoms - (ANSWER)covalent
transfer of electrons between two atoms - (ANSWER)ionic
what is a weak bond? - (ANSWER)hydrogen bond
the H atom forms one covalent bond and a second weaker bond with an atom in
another molecules - (ANSWER)hydrogen bond
,2
equal sharing of electrons
(two of the same element) - (ANSWER)nonpolar
unequal sharing of electrons
has a charge
(water) - (ANSWER)polar
what is the charge of O in water? - (ANSWER)negative
what is the charge of H in water? - (ANSWER)positive
interactions between water molecules
(H2O with H2O) - (ANSWER)cohesion
interactions between water and other molecules - (ANSWER)solvent
what is the maximum amount of bonds that hydrogen can form? - (ANSWER)4
bonds
in room temperature of water what % is the maximum amount of bonds going to
be made? - (ANSWER)15%
, 3
when H+ concentration increases... - (ANSWER)more acidic
what H- concentration decreases... - (ANSWER)more basic
affinity for water
(polar and ionic bonds) - (ANSWER)hydrophilic
repel water
(nonpolar covalent bonds) - (ANSWER)hydrophobic
chemical processes are sensitive to pH changes and resist change in the pH
solution - (ANSWER)buffers
the pH of human blood is... - (ANSWER)7.4
what are the main buffers in blood? - (ANSWER)carbonic acid and bicarbonate
response to a rise in pH in blood (becomes more basic) - (ANSWER)right
response to a drop in pH in blood (becomes more acidic) - (ANSWER)left
building blocks for biological molecules - (ANSWER)carbon atoms
