BIOLOGY 101 EXAM 1 UNC QUESTIONS &
DETAILED CORRECT SOLUTIONS RATED 100%
COMPLETE
1. Molecules A molecule is a group of atoms held together by
chemical bonds that store potential energy.
A molecule is formed by 2 to several dozens of atoms
Some molecules have large amounts of potential
energy (PF) in their chemical bonds, they serve as
"Energy Molecules" that provide kinetic energy for all
cell activities when their chemical bonds are broken.
2. Adenosine Is a universal energy molecule found in almost all living
Triphosphate (ATP) organ- isms
3. Macromolecule A macromolecule is formed by hundreds or thousands of
atoms
4. Chemical bonding's: Formed by atoms being attracted to each other due to
Ionic Bonds opposite electrical charges.
• A cation (positive charge) and an anion (negative
charge) are usually involved in ionic bonds.
(e.g. Na++ Cl-’NaCl).
5. Chemical Bonding's: Formed by the sharing of electrons between 2 atoms
Cova- lent bonds (e.g. H2O).
,BIOLOGY 101 EXAM 1 UNC QUESTIONS &
DETAILED CORRECT SOLUTIONS RATED 100%
COMPLETE
• Atoms that form covalent bonds not
only gain extra potential energy, they
become more stable because of more
electrons on outer orbits.
• Strongest type of chemical bonding
in biological molecules
,BIOLOGY 101 EXAM 1 UNC QUESTIONS &
DETAILED CORRECT SOLUTIONS RATED 100%
COMPLETE
• Allowing cells to build larger molecules and
macromolecules.
*Very strong bond; very difficult to break but once broken it
releases lots of energy.
6. Electronegativity The attraction of an atom for
shared electrons.
If the atoms in a molecule have SIMILAR electronegativity, the
electrons remain equally stored between 2 nuclei and the
cova- lent bond is said to be NON-POLAR.
If one element is more electronegative, it pulls the shared elec-
trons closer to itself,
creating POLAR covalent bond.
7. Chemical Bonding's: Weakest chemical bond; but very important bc it plays a
Hydro- gen Bonds key role in forming internal shaping and folding of
larger molecules.; can break and be remade again.
• Hydrogen atoms contain only 1 proton and 1
electron, as a result when it is sharing its electron with
another atom, it has a partial
positive charge (i.e. H+).
• H+ tends to be attracted to the partial negative
charge of oxygen (O-) and nitrogen (N-), forming
, BIOLOGY 101 EXAM 1 UNC QUESTIONS &
DETAILED CORRECT SOLUTIONS RATED 100%
COMPLETE
hydrogen bonds.
DETAILED CORRECT SOLUTIONS RATED 100%
COMPLETE
1. Molecules A molecule is a group of atoms held together by
chemical bonds that store potential energy.
A molecule is formed by 2 to several dozens of atoms
Some molecules have large amounts of potential
energy (PF) in their chemical bonds, they serve as
"Energy Molecules" that provide kinetic energy for all
cell activities when their chemical bonds are broken.
2. Adenosine Is a universal energy molecule found in almost all living
Triphosphate (ATP) organ- isms
3. Macromolecule A macromolecule is formed by hundreds or thousands of
atoms
4. Chemical bonding's: Formed by atoms being attracted to each other due to
Ionic Bonds opposite electrical charges.
• A cation (positive charge) and an anion (negative
charge) are usually involved in ionic bonds.
(e.g. Na++ Cl-’NaCl).
5. Chemical Bonding's: Formed by the sharing of electrons between 2 atoms
Cova- lent bonds (e.g. H2O).
,BIOLOGY 101 EXAM 1 UNC QUESTIONS &
DETAILED CORRECT SOLUTIONS RATED 100%
COMPLETE
• Atoms that form covalent bonds not
only gain extra potential energy, they
become more stable because of more
electrons on outer orbits.
• Strongest type of chemical bonding
in biological molecules
,BIOLOGY 101 EXAM 1 UNC QUESTIONS &
DETAILED CORRECT SOLUTIONS RATED 100%
COMPLETE
• Allowing cells to build larger molecules and
macromolecules.
*Very strong bond; very difficult to break but once broken it
releases lots of energy.
6. Electronegativity The attraction of an atom for
shared electrons.
If the atoms in a molecule have SIMILAR electronegativity, the
electrons remain equally stored between 2 nuclei and the
cova- lent bond is said to be NON-POLAR.
If one element is more electronegative, it pulls the shared elec-
trons closer to itself,
creating POLAR covalent bond.
7. Chemical Bonding's: Weakest chemical bond; but very important bc it plays a
Hydro- gen Bonds key role in forming internal shaping and folding of
larger molecules.; can break and be remade again.
• Hydrogen atoms contain only 1 proton and 1
electron, as a result when it is sharing its electron with
another atom, it has a partial
positive charge (i.e. H+).
• H+ tends to be attracted to the partial negative
charge of oxygen (O-) and nitrogen (N-), forming
, BIOLOGY 101 EXAM 1 UNC QUESTIONS &
DETAILED CORRECT SOLUTIONS RATED 100%
COMPLETE
hydrogen bonds.
