BIOL271: Microbiology w/Lab
2026 – 2027 | Portage Learning
Module 1: Intro to Microbiology, Prokaryotes vs Eukaryotes,
Cellular Organelles and Arrangements
Exam Review | LockDown Browser
By PortageMaster
Question 1
A virus is considered a microorganism.
• True
• ✓ False
Correct Answer: False
Feedback: Viruses are not classified as living microorganisms because they lack cellular structure and
cannot reproduce independently of a host cell. They are acellular infectious agents.
Question 2
The smallest biological unit of life is the ______.
• Atom
• Molecule
• ✓ Cell
• Tissue
• Organelle
Correct Answer: Cell
Feedback: The cell is the smallest unit capable of carrying out all the processes of life (metabolism,
reproduction, response to stimuli).
Question 3
At a generalized level, all cells are comprised of what?
• ✓ Proteins, Lipids, Nucleic acids and Carbohydrates
• Proteins, Lipids, Vitamins and Minerals
• Proteins, Sugars, DNA and Water
• Carbohydrates, Fats, Salts and Enzymes
Correct Answer: Proteins, Lipids, Nucleic acids and Carbohydrates
Feedback: All cells share four fundamental macromolecule classes: proteins, lipids, nucleic acids,
and carbohydrates.
, Question 4
How many different types of amino acids are available from which to make proteins?
• 10
• 16
• ✓ 20
• 24
• 64
Correct Answer: 20
Feedback: There are 20 standard amino acids that combine in different sequences to form all cellular
proteins.
Question 5
Define an essential amino acid.
✓ Answer: An essential amino acid is one that cannot be produced by the human body
and must be taken in from the environment through alternative sources (i.e., food).
Feedback: Humans have 9 essential amino acids: histidine, isoleucine, leucine, lysine, methionine,
phenylalanine, threonine, tryptophan, and valine.
Question 6
What are the two major types of nucleic acids and their roles?
✓ Answer: DNA (deoxyribonucleic acid) — carries vast hereditary information and is
responsible for the inheritable characteristics of living organisms. RNA (ribonucleic
acid) — deciphers the hereditary information in DNA and uses it to synthesize proteins.
Feedback: Both are polymers of nucleotides. DNA uses thymine and is typically double-stranded; RNA
uses uracil and is typically single-stranded.
Question 7
Complete the following DNA strand, and indicate how many bonds are formed for each
complementary pair:
3' GGTCATCG 5'
5' CC___AGC 3'
✓ Answer: 3' GGTCATCG 5'
5' CCAGTAGC 3'
There are 2 hydrogen bonds between A and T, and 3 hydrogen bonds between G and C.
Feedback: A-T pairs share 2 H-bonds; G-C pairs share 3 H-bonds, making G-C-rich regions more
stable.
2026 – 2027 | Portage Learning
Module 1: Intro to Microbiology, Prokaryotes vs Eukaryotes,
Cellular Organelles and Arrangements
Exam Review | LockDown Browser
By PortageMaster
Question 1
A virus is considered a microorganism.
• True
• ✓ False
Correct Answer: False
Feedback: Viruses are not classified as living microorganisms because they lack cellular structure and
cannot reproduce independently of a host cell. They are acellular infectious agents.
Question 2
The smallest biological unit of life is the ______.
• Atom
• Molecule
• ✓ Cell
• Tissue
• Organelle
Correct Answer: Cell
Feedback: The cell is the smallest unit capable of carrying out all the processes of life (metabolism,
reproduction, response to stimuli).
Question 3
At a generalized level, all cells are comprised of what?
• ✓ Proteins, Lipids, Nucleic acids and Carbohydrates
• Proteins, Lipids, Vitamins and Minerals
• Proteins, Sugars, DNA and Water
• Carbohydrates, Fats, Salts and Enzymes
Correct Answer: Proteins, Lipids, Nucleic acids and Carbohydrates
Feedback: All cells share four fundamental macromolecule classes: proteins, lipids, nucleic acids,
and carbohydrates.
, Question 4
How many different types of amino acids are available from which to make proteins?
• 10
• 16
• ✓ 20
• 24
• 64
Correct Answer: 20
Feedback: There are 20 standard amino acids that combine in different sequences to form all cellular
proteins.
Question 5
Define an essential amino acid.
✓ Answer: An essential amino acid is one that cannot be produced by the human body
and must be taken in from the environment through alternative sources (i.e., food).
Feedback: Humans have 9 essential amino acids: histidine, isoleucine, leucine, lysine, methionine,
phenylalanine, threonine, tryptophan, and valine.
Question 6
What are the two major types of nucleic acids and their roles?
✓ Answer: DNA (deoxyribonucleic acid) — carries vast hereditary information and is
responsible for the inheritable characteristics of living organisms. RNA (ribonucleic
acid) — deciphers the hereditary information in DNA and uses it to synthesize proteins.
Feedback: Both are polymers of nucleotides. DNA uses thymine and is typically double-stranded; RNA
uses uracil and is typically single-stranded.
Question 7
Complete the following DNA strand, and indicate how many bonds are formed for each
complementary pair:
3' GGTCATCG 5'
5' CC___AGC 3'
✓ Answer: 3' GGTCATCG 5'
5' CCAGTAGC 3'
There are 2 hydrogen bonds between A and T, and 3 hydrogen bonds between G and C.
Feedback: A-T pairs share 2 H-bonds; G-C pairs share 3 H-bonds, making G-C-rich regions more
stable.
