Biology Practice Exam comprehensive
Questions and Answers with Verified
Solutions
Question 1:
One type of molecule that contributes to coronary artery disease is
apolipoprotein A, a type of protein bound to a cholesterol molecule which
is collectively referred to as lp(a). Part 1) Apolipoprotein A binds to
cholesterol to form lp(a). Which type of molecule is cholesterol? Part 2)
Apolipoprotein A is the protein portion of lp(a). Which type of reaction
occurs with which type of monomer to make apolipoprotein A? Part 3)
Apolipoprotein a has an isoelectric point (pI) of 5.71. The isoelectric point
of a protein is the pH at which the protein carries no net charges (i.e. it is
not positively charged nor negatively charged). Which statement about
the pI of apolipoprotein A is true?
Answer:
Part 1) Lipid Part 2) Dehydration synthesis reactions with amino acids
Part 3) Apolipoprotein A carries no net charge when hydrogen ion
concentration is high and pH is acidic (Higher hydrogen ion concentration
results in acidic pH ( < 7).)
Question 2:
The structure diagrammed here is formaldehyde—a major ingredient in
the embalming fluid used to preserve human cadavers. Which of the
,following statements are true? Choose all that apply: To show water
interacting with formaldehyde, you should draw an O on water forming a
covalent bond with the O on formaldehyde. Formaldehyde is an organic
compound (meaning, carbon-containing), and organic compounds only
dissolve in other organics—not water. Formaldehyde is soluble in water
because the C = O bond is polar, giving O a partial negative charge. To
show water interacting with formaldehyde, you should draw Os on water
forming a hydrogen bond
Answer:
Formaldehyde is soluble in water because the C = O bond is polar, giving
O a partial negative charge.
Question 3:
Bacteria live in every conceivable habitat: from snowfields to boiling hot
springs, as well as your skin and digestive tract. The percentage of GC
pairs in bacterial genes also varies widely from species to species. Which
of the following statements is the most logical prediction, based on your
understanding of nucleic acid structure?
Answer:
Genes with many GC pairs are more common in bacteria that live in hot
habitats, because they are more stable.
, Question 4:
Genes in some viruses—including HIV and COVID—consist of RNA.
During an infection, special machines make a DNA copy of the virus's
genes. Suppose that one of these viruses had the following RNA
sequence: UUAAGCGCGUC. What would the DNA copy of this
sequence--meaning, the DNA produced as a complementary
sequence--look like? (As usual, all sequences are written 5' to 3' here.)
Answer:
GACGCGCTTAA
Question 5:
The structure of an amino acid is shown below. Which of the following
processes would be affected by removal of the amino group? Select all
that apply. formation of phosphate bonds between nearby amino acids
formation of hydrogen bonds between amino acids formation of peptide
bonds between amino acids formation of sulfhydryl bonds between amino
acids
Answer:
formation of hydrogen bonds between amino acids; formation of peptide
bonds between amino acids
Question 6:
areas that include a complete peptide bond.
Answer:
In between NCC
Questions and Answers with Verified
Solutions
Question 1:
One type of molecule that contributes to coronary artery disease is
apolipoprotein A, a type of protein bound to a cholesterol molecule which
is collectively referred to as lp(a). Part 1) Apolipoprotein A binds to
cholesterol to form lp(a). Which type of molecule is cholesterol? Part 2)
Apolipoprotein A is the protein portion of lp(a). Which type of reaction
occurs with which type of monomer to make apolipoprotein A? Part 3)
Apolipoprotein a has an isoelectric point (pI) of 5.71. The isoelectric point
of a protein is the pH at which the protein carries no net charges (i.e. it is
not positively charged nor negatively charged). Which statement about
the pI of apolipoprotein A is true?
Answer:
Part 1) Lipid Part 2) Dehydration synthesis reactions with amino acids
Part 3) Apolipoprotein A carries no net charge when hydrogen ion
concentration is high and pH is acidic (Higher hydrogen ion concentration
results in acidic pH ( < 7).)
Question 2:
The structure diagrammed here is formaldehyde—a major ingredient in
the embalming fluid used to preserve human cadavers. Which of the
,following statements are true? Choose all that apply: To show water
interacting with formaldehyde, you should draw an O on water forming a
covalent bond with the O on formaldehyde. Formaldehyde is an organic
compound (meaning, carbon-containing), and organic compounds only
dissolve in other organics—not water. Formaldehyde is soluble in water
because the C = O bond is polar, giving O a partial negative charge. To
show water interacting with formaldehyde, you should draw Os on water
forming a hydrogen bond
Answer:
Formaldehyde is soluble in water because the C = O bond is polar, giving
O a partial negative charge.
Question 3:
Bacteria live in every conceivable habitat: from snowfields to boiling hot
springs, as well as your skin and digestive tract. The percentage of GC
pairs in bacterial genes also varies widely from species to species. Which
of the following statements is the most logical prediction, based on your
understanding of nucleic acid structure?
Answer:
Genes with many GC pairs are more common in bacteria that live in hot
habitats, because they are more stable.
, Question 4:
Genes in some viruses—including HIV and COVID—consist of RNA.
During an infection, special machines make a DNA copy of the virus's
genes. Suppose that one of these viruses had the following RNA
sequence: UUAAGCGCGUC. What would the DNA copy of this
sequence--meaning, the DNA produced as a complementary
sequence--look like? (As usual, all sequences are written 5' to 3' here.)
Answer:
GACGCGCTTAA
Question 5:
The structure of an amino acid is shown below. Which of the following
processes would be affected by removal of the amino group? Select all
that apply. formation of phosphate bonds between nearby amino acids
formation of hydrogen bonds between amino acids formation of peptide
bonds between amino acids formation of sulfhydryl bonds between amino
acids
Answer:
formation of hydrogen bonds between amino acids; formation of peptide
bonds between amino acids
Question 6:
areas that include a complete peptide bond.
Answer:
In between NCC
