GENERAL BIOLOGY PHYSIOLOGY AND
CELL BIOLOGY (Biol 105) TEST 1
STUDY GUIDE QUESTIONS AND
ACCURATE SOLUTIONS.
,1. An atom that is neutrally charged contains: the same number of protons and
electrons.
Everything is mase up of atoms, the three parts that make up an atom are A
Proton (+), Electron (-) and Neutron (no charge), to have a neutrally
charged atom you need an even number of Protons and Electrons. Different
numbers of Neutrons change the Isotopes but not the element. The number
of protons determines the identity of an atom.
2. What part of the atom determines how the atom reacts chemically? Electron
, Atoms react with each other (via electrons) to form chemical bonds. The
number of electrons in the outermost shell determines the reactivity of an
atom. Atoms with unfilled orbitals are unstable and will undergo reactions
to fill the orbitals. Elements with the same number of electrons in the
outermost (valence) shell share similar reactive properties.
3. The hydrogen bond between two water molecules arises because water is: polar.
Polar covalent bond: A covalent bond in which the electron density is
unevenly shared between the two bonded atoms, due to a difference in
electronegativity or due to inductive effects. Water is always Polar because
the oxygen end is partially negative, O- ; the hydrogen ends are partially
positive, O+. This makes one end positive and one end negative.
4. Which of the following is not a correct monomer/polymer pairing?
Cellulose/triglyceride
• Monomers are units that are building blocks of macromolecular polymers.
, combine with each other using bonds to form larger molecules known as polymers.
Here, the prefix poly- means many, and -Mer means unit. For the word “monomer,”
we have already seen that -Mer means unit; well mono- means one. We can combine
this information to learn that polymers consist of single, repeating subunits that are
called monomers. Cellulose is a building block of plant cells and fiber. Triglycerides
are a type of fat that circulates in your blood. Your body makes triglycerides or gets
them from the foods you eat. Since triglycerides, which is made up of three fatty
acids attached to a glycerol molecule by ester bonds. Since fatty acids are not made
up of repeating subunits, they are not polymers.
5. Each amino acid has a unique group. “R”
Amino acids are both an acid and a base. The carboxyl group is an acid (a proton
donor); the amino group is a base (proton acceptor). The side chain contains various
functional groups that determine the properties of amino acids. There are 20
different amino acids encoded by DNA. R groups on the surface interact with other
molecules via ionic, hydrophobic, or hydrogen bonds. R groups can determine
protein structure and thus function
6. Polysaccharides, polypeptides, and polynucleotides: may be broken down in
hydrolysis reactions.
Polysaccharides Are a large carbohydrate molecule. It contains many small sugar
molecules that are joined chemically. Also called glycan. Polypeptides Are a
substance that contains many amino acids polynucleotides are a compound
comprised of several nucleotides. All of these can be broken down by a hydrolysis
CELL BIOLOGY (Biol 105) TEST 1
STUDY GUIDE QUESTIONS AND
ACCURATE SOLUTIONS.
,1. An atom that is neutrally charged contains: the same number of protons and
electrons.
Everything is mase up of atoms, the three parts that make up an atom are A
Proton (+), Electron (-) and Neutron (no charge), to have a neutrally
charged atom you need an even number of Protons and Electrons. Different
numbers of Neutrons change the Isotopes but not the element. The number
of protons determines the identity of an atom.
2. What part of the atom determines how the atom reacts chemically? Electron
, Atoms react with each other (via electrons) to form chemical bonds. The
number of electrons in the outermost shell determines the reactivity of an
atom. Atoms with unfilled orbitals are unstable and will undergo reactions
to fill the orbitals. Elements with the same number of electrons in the
outermost (valence) shell share similar reactive properties.
3. The hydrogen bond between two water molecules arises because water is: polar.
Polar covalent bond: A covalent bond in which the electron density is
unevenly shared between the two bonded atoms, due to a difference in
electronegativity or due to inductive effects. Water is always Polar because
the oxygen end is partially negative, O- ; the hydrogen ends are partially
positive, O+. This makes one end positive and one end negative.
4. Which of the following is not a correct monomer/polymer pairing?
Cellulose/triglyceride
• Monomers are units that are building blocks of macromolecular polymers.
, combine with each other using bonds to form larger molecules known as polymers.
Here, the prefix poly- means many, and -Mer means unit. For the word “monomer,”
we have already seen that -Mer means unit; well mono- means one. We can combine
this information to learn that polymers consist of single, repeating subunits that are
called monomers. Cellulose is a building block of plant cells and fiber. Triglycerides
are a type of fat that circulates in your blood. Your body makes triglycerides or gets
them from the foods you eat. Since triglycerides, which is made up of three fatty
acids attached to a glycerol molecule by ester bonds. Since fatty acids are not made
up of repeating subunits, they are not polymers.
5. Each amino acid has a unique group. “R”
Amino acids are both an acid and a base. The carboxyl group is an acid (a proton
donor); the amino group is a base (proton acceptor). The side chain contains various
functional groups that determine the properties of amino acids. There are 20
different amino acids encoded by DNA. R groups on the surface interact with other
molecules via ionic, hydrophobic, or hydrogen bonds. R groups can determine
protein structure and thus function
6. Polysaccharides, polypeptides, and polynucleotides: may be broken down in
hydrolysis reactions.
Polysaccharides Are a large carbohydrate molecule. It contains many small sugar
molecules that are joined chemically. Also called glycan. Polypeptides Are a
substance that contains many amino acids polynucleotides are a compound
comprised of several nucleotides. All of these can be broken down by a hydrolysis
