MCAT Biochemistry Chapter 5 Lipids All Answers Correct
What type of microorganism is *Escherichia coli* (E. coli)?
✔️✔️ *Escherichia coli* (E. coli) is a bacterium.
How do viruses differ from bacteria in their structure and reproduction?
✔️✔️ Viruses lack cellular structures and cannot reproduce independently; they need a host cell to
replicate.
What is the main function of chloroplasts in algae and plant cells?
✔️✔️ Chloroplasts carry out photosynthesis, converting sunlight into energy.
How do halophiles adapt to high-salt environments?
✔️✔️ Halophiles produce compatible solutes that help them retain water and prevent cell
dehydration in salty environments.
What is the role of the protein flagellin in bacterial cells?
✔️✔️ Flagellin forms the structure of flagella, enabling bacterial motility.
What is the purpose of heat-fixing a bacterial smear before staining?
✔️✔️ Heat-fixing kills bacteria, adheres them to the slide, and prepares the cells to take up stains.
What is the primary role of endoplasmic reticulum (ER) in eukaryotic cells?
✔️✔️ The ER synthesizes proteins (rough ER) and lipids (smooth ER) and transports them within the
cell.
Define “antigen.”
, ✔️✔️ An antigen is a foreign substance that triggers an immune response, often recognized by
antibodies.
What is horizontal gene transfer in bacteria?
✔️✔️ Horizontal gene transfer is the exchange of genetic material between bacteria, allowing rapid
genetic variation.
How do bacteriostatic agents differ from bactericidal agents?
✔️✔️ Bacteriostatic agents inhibit bacterial growth, while bactericidal agents kill bacteria.
What type of bacteria have lipopolysaccharides (LPS) in their outer membrane?
✔️✔️ Gram-negative bacteria have lipopolysaccharides in their outer membrane.
What are “opsonins,” and what is their function in the immune system?
✔️✔️ Opsonins mark pathogens for phagocytosis, making them easier for immune cells to recognize
and engulf.
Explain the difference between sterilization and pasteurization.
✔️✔️ Sterilization kills all forms of life, while pasteurization reduces microbial load without
eliminating all microbes.
How does a spore differ from a vegetative bacterial cell?
✔️✔️ A spore is a dormant, resistant form of a bacterial cell, while a vegetative cell is active and
reproducing.
What are fimbriae, and what role do they play in bacteria?
✔️✔️ Fimbriae are hair-like structures that help bacteria adhere to surfaces and host cells.
How do acid-fast bacteria differ from other bacteria?
What type of microorganism is *Escherichia coli* (E. coli)?
✔️✔️ *Escherichia coli* (E. coli) is a bacterium.
How do viruses differ from bacteria in their structure and reproduction?
✔️✔️ Viruses lack cellular structures and cannot reproduce independently; they need a host cell to
replicate.
What is the main function of chloroplasts in algae and plant cells?
✔️✔️ Chloroplasts carry out photosynthesis, converting sunlight into energy.
How do halophiles adapt to high-salt environments?
✔️✔️ Halophiles produce compatible solutes that help them retain water and prevent cell
dehydration in salty environments.
What is the role of the protein flagellin in bacterial cells?
✔️✔️ Flagellin forms the structure of flagella, enabling bacterial motility.
What is the purpose of heat-fixing a bacterial smear before staining?
✔️✔️ Heat-fixing kills bacteria, adheres them to the slide, and prepares the cells to take up stains.
What is the primary role of endoplasmic reticulum (ER) in eukaryotic cells?
✔️✔️ The ER synthesizes proteins (rough ER) and lipids (smooth ER) and transports them within the
cell.
Define “antigen.”
, ✔️✔️ An antigen is a foreign substance that triggers an immune response, often recognized by
antibodies.
What is horizontal gene transfer in bacteria?
✔️✔️ Horizontal gene transfer is the exchange of genetic material between bacteria, allowing rapid
genetic variation.
How do bacteriostatic agents differ from bactericidal agents?
✔️✔️ Bacteriostatic agents inhibit bacterial growth, while bactericidal agents kill bacteria.
What type of bacteria have lipopolysaccharides (LPS) in their outer membrane?
✔️✔️ Gram-negative bacteria have lipopolysaccharides in their outer membrane.
What are “opsonins,” and what is their function in the immune system?
✔️✔️ Opsonins mark pathogens for phagocytosis, making them easier for immune cells to recognize
and engulf.
Explain the difference between sterilization and pasteurization.
✔️✔️ Sterilization kills all forms of life, while pasteurization reduces microbial load without
eliminating all microbes.
How does a spore differ from a vegetative bacterial cell?
✔️✔️ A spore is a dormant, resistant form of a bacterial cell, while a vegetative cell is active and
reproducing.
What are fimbriae, and what role do they play in bacteria?
✔️✔️ Fimbriae are hair-like structures that help bacteria adhere to surfaces and host cells.
How do acid-fast bacteria differ from other bacteria?
