AP Bio MCQ Progress Check Unit 4 questions
answers with solutions
An antigen can induce an immune response in a host organism. Antigens are targeted by
antibodies that are produced by the organism's immune system in response to contact with the
antigen. Antibodies are specific to antigens. Many different cell types are involved in immune
responses.
Which of the following best describes the role of cell-to-cell communication during a response
to an invasion of antigens?
A
Chemicals that are secreted from antigen-presenting cells then activate helper T cells.
B
A macrophage cell engulfs a pathogen in the blood.
C
Antigens attaching to receptors on memory B cells stimulate the memory B cells to become
plasma cells.
D
Antigen-presenting cells engulf antigens at the first exposure. - ANSWER A
Adjacent plant cells have narrow channels called plasmodesmata that pass through the cell
walls of the connected cells and allow a cytoplasmic connection between the cells.
Which of the following statements best describes a primary function of plasmodesmata?
A
They allow the movement of molecules from one cell to another, enabling communication
between cells.
B
They prevent the cell membrane from pulling away from the cell wall during periods of drought.
C
, They eliminate the need to produce signaling molecules and eliminate the need for cells to have
receptors for signaling molecules.
D
They increase the surface area available for attachment of ribosomes and thus increase protein
synthesis. - ANSWER A
A hydrophilic peptide hormone is produced in the anterior pituitary gland located at the base of
the brain. The hormone targets specific cells in many parts of the body.
Which of the following best explains a possible mechanism that would enable the hormone to
efficiently reach all of the target cells in the body?
A
The hormone interacts with the nerves at the base of the brain and directs signals to the target
cells through the nervous system.
B
The hormone diffuses into target cells adjacent to the anterior pituitary gland, where the
hormone is degraded.
C
The hormone is released into the bloodstream where it can be transported to all cells with the
correct receptors.
D
The hormone moves through cytoplasmic connections between cells until it has reached all cells
with the correct intracellular binding sites. - ANSWER C
G proteins are a family of receptor proteins that are involved in transmitting signals from
outside a cell to inside a cell. When a signaling molecule binds to a G protein, the G protein is
activated. The G protein then activates an enzyme that produces a second messenger called
cAMP.
Which of the following describes a critical role of cAMP during the transduction stage of a G
protein signal transduction pathway?
A
answers with solutions
An antigen can induce an immune response in a host organism. Antigens are targeted by
antibodies that are produced by the organism's immune system in response to contact with the
antigen. Antibodies are specific to antigens. Many different cell types are involved in immune
responses.
Which of the following best describes the role of cell-to-cell communication during a response
to an invasion of antigens?
A
Chemicals that are secreted from antigen-presenting cells then activate helper T cells.
B
A macrophage cell engulfs a pathogen in the blood.
C
Antigens attaching to receptors on memory B cells stimulate the memory B cells to become
plasma cells.
D
Antigen-presenting cells engulf antigens at the first exposure. - ANSWER A
Adjacent plant cells have narrow channels called plasmodesmata that pass through the cell
walls of the connected cells and allow a cytoplasmic connection between the cells.
Which of the following statements best describes a primary function of plasmodesmata?
A
They allow the movement of molecules from one cell to another, enabling communication
between cells.
B
They prevent the cell membrane from pulling away from the cell wall during periods of drought.
C
, They eliminate the need to produce signaling molecules and eliminate the need for cells to have
receptors for signaling molecules.
D
They increase the surface area available for attachment of ribosomes and thus increase protein
synthesis. - ANSWER A
A hydrophilic peptide hormone is produced in the anterior pituitary gland located at the base of
the brain. The hormone targets specific cells in many parts of the body.
Which of the following best explains a possible mechanism that would enable the hormone to
efficiently reach all of the target cells in the body?
A
The hormone interacts with the nerves at the base of the brain and directs signals to the target
cells through the nervous system.
B
The hormone diffuses into target cells adjacent to the anterior pituitary gland, where the
hormone is degraded.
C
The hormone is released into the bloodstream where it can be transported to all cells with the
correct receptors.
D
The hormone moves through cytoplasmic connections between cells until it has reached all cells
with the correct intracellular binding sites. - ANSWER C
G proteins are a family of receptor proteins that are involved in transmitting signals from
outside a cell to inside a cell. When a signaling molecule binds to a G protein, the G protein is
activated. The G protein then activates an enzyme that produces a second messenger called
cAMP.
Which of the following describes a critical role of cAMP during the transduction stage of a G
protein signal transduction pathway?
A
