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