Which of the following allows a limited range of immune cells to detect and respond rapidly to a wide range of pathogens that share common structures?
A. Pattern recognition receptors (PRRs)
B. Cytokines
C. Chemokines
D. T cells .
Pattern recognition receptors (PRRs) are a class of receptors that can directly recognize the specific molecular structures on the surface of pathogens.
PRRs play a crucial role in the proper function of the innate immune system and are germline-encoded host sensors, which detect molecules typical for the pathogens.
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Choice B is incorrect because cytokines are not receptors but rather signaling molecules that regulate immunity.
Choice C is incorrect because chemokines are not receptors but rather signaling molecules that attract immune cells to sites of infection.
Choice D is incorrect because T cells are not receptors but rather white blood cells that assist B cells or directly kill infected cells.
Therefore, the Correct Answer is A.
More Questions on TEAS 7 Science
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Q #1: Which of the following organelles is responsible for modifying, sorting and packaging proteins and lipids?
A. Golgi apparatus
B. Mitochondria
C. Ribosomes
D. Endoplasmic reticulum
Answer Explanation
The correct answer is choice A. Golgi apparatus.
The Golgi apparatus is a membrane-bound organelle that is responsible for transporting, modifying, and packaging proteins and lipids into vesicles for delivery to targeted destinations.
Choice B is incorrect because mitochondria are responsible for energy production.
Choice C is incorrect because ribosomes are responsible for protein production.
Choice D is incorrect because the endoplasmic reticulum is responsible for lipid production and protein production, but not for modifying, sorting and packaging proteins and lipids.
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Q #2: What is the function of the neuromuscular junction?
A. To connect muscle fibers to motor neurons
B. To bind acetylcholine to nAChRs
C. To depolarize the muscle cell membrane D.
D. To activate voltage-gated sodium channels on the muscle membrane .
Answer Explanation
The neuromuscular junction is a type of synapse where neuronal signals from the brain or spinal cord interact with skeletal muscle fibers, causing them to contract.
The activation of many muscle fibers together causes muscles to contract, which in turn can produce movement.
Choice B is incorrect because binding acetylcholine to nAChRs is a process that occurs at the neuromuscular junction, but it is not the function of the neuromuscular junction itself.
Choice C is incorrect because depolarizing the muscle cell membrane is a result of the function of the neuromuscular junction, but it is not the function itself.
Choice D is incorrect because activating voltage-gated sodium channels on the muscle membrane is a result of the function of the neuromuscular junction, but it is not the function itself.
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Q #3: What is the hallmark of adaptive immunity?
A. Rapid recruitment of immune cells to sites of infection and inflammation
B. Antigen-independent defense mechanism
C. Immunologic memory
D. Non-specific host-defense mechanisms .
Answer Explanation
Immunologic memory is the hallmark of adaptive immunity.
Immunologic memory enables the host to mount a more rapid and efficient immune response upon subsequent exposure to the antigen.
Choice A is incorrect because rapid recruitment of immune cells to sites of infection and inflammation is a characteristic of innate immunity.
Choice B is incorrect because antigen-independent defense mechanisms are characteristic of innate immunity.
Choice D is incorrect because non-specific host-defense mechanisms are characteristic of innate immunity.
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Q #4: Which subatomic particle contributes to the positive charge of an atom?
A. Proton
B. Neutron
C. Electron
D. Nucleon
Answer Explanation
Protons contribute to the positive charge of an atom.
Protons are subatomic particles with a positive charge found in the nucleus of an atom.
Choice B is incorrect because neutrons are neutral and do not have a charge. Choice C is incorrect because electrons have a negative charge.
Choice D is incorrect because nucleons refer to both protons and neutrons, but only protons contribute to the positive charge of an atom.
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Q #5: What is the organelle that encapsulates the contents of the cell and plays a vital role in regulating the movement of substances in and out of the cell?.
A. Ribosome
B. Nucleus
C. Mitochondria
D. Plasma membrane.
Answer Explanation
The plasma membrane is the organelle that encapsulates the contents of the cell and plays a vital role in regulating the movement of substances in and out of the cell.
It is a selectively permeable barrier that separates the internal environment of the cell from the external environment.
Choice A is incorrect because ribosomes are organelles involved in protein synthesis, not in regulating the movement of substances in and out of the cell.
Choice B is incorrect because the nucleus is an organelle that contains the cell’s genetic material, not in regulating the movement of substances in and out of the cell.
Choice C is incorrect because mitochondria are organelles involved in energy production, not in regulating the movement of substances in and out of the cell.
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Q #6: Which organ in the human body is responsible for the removal of damaged red blood cells and the production of certain types of white blood cells?
A. Spleen
B. Kidneys
C. Pancreas
D. Thyroid gland
Answer Explanation
The correct answer is choice A.
The spleen is an organ in the human body that is responsible for the removal of damaged red blood cells and the production of certain types of white blood cells.
Choice B is incorrect because the kidneys are responsible for filtering waste from the blood and regulating electrolyte balance.
Choice C is incorrect because the pancreas produces hormones and enzymes that aid in digestion.
Choice D is incorrect because the thyroid gland produces hormones that regulate metabolism.
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Q #7: A patient with a history of heart failure is prescribed a medication that increases urine output to reduce fluid buildup. Which of the following statements best describes the mechanism of action of the prescribed medication?
A. Inhibits the renin-angiotensin-aldosterone system.
B. Blocks beta receptors.
C. Increases sodium and water reabsorption.
D. Enhances glomerular filtration rate.
Answer Explanation
The correct answer is choice D - Enhances glomerular filtration rate.
The medication prescribed to the patient is a diuretic, which removes water and electrolytes from the body by increasing urination 1.
This helps reduce fluid buildup in the body.
Choice A, Inhibits the renin-angiotensin-aldosterone system, is not the correct answer because it describes a different mechanism of action.
Choice B, Blocks beta receptors, is not the correct answer because it describes a different mechanism of action.
Choice C, Increases sodium and water reabsorption, is not the correct answer because it would have the opposite effect of reducing fluid buildup.
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Q #8: A nurse is conducting a research study to compare the effects of two different pain medications on postoperative patients. The nurse randomly assigns the patients to either receive medication A or medication B. Which of the following is the best way to ensure that the study is valid and reliable?
A. Use a large sample size and a standardized procedure for administering the medications.
B. Use a placebo group and a double-blind technique for giving the medications.
C. Use a matched-pairs design and a crossover technique for switching the medications.
D. Use a convenience sample and a pretest-posttest design for measuring the pain levels.
Answer Explanation
The correct answer is choice B.
Using a placebo group and a double-blind technique for giving the medications is the best way to ensure that the study is valid and reliable.
A placebo group helps control for the placebo effect, which can influence the results of a study.
A double-blind technique means that neither the patients nor the researchers know which medication is being given, reducing bias.
Choice A is not the best answer because while a large sample size and standardized procedure can increase reliability, they do not address validity.
Choice C is not the best answer because a matched-pairs design and crossover technique are useful for reducing variability but do not address validity.
Choice D is not the best answer because a convenience sample may not be representative and a pretest-posttest design does not control for extraneous variables.
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Q #9: Which of the following refers to a condition in which a patient experiences difficulty breathing while lying down, but their breathing improves when they sit up or stand?
A. Orthopnea
B. Hypoxia
C. Tachypnea
D. Bradypnea
Answer Explanation
The correct answer is choice A. Orthopnea.
Orthopnea refers to a condition in which a patient experiences difficulty breathing while lying down, but their breathing improves when they sit up or stand.
Choice B, Hypoxia, is not the correct answer because it refers to a condition in which there is a lack of oxygen supply to the body’s tissues.
Choice C, Tachypnea, is not the correct answer because it refers to rapid breathing.
Choice D, Bradypnea, is not the correct answer because it refers to abnormally slow breathing.
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Q #10: Which of the following represents the first line of defense to an intruding pathogen?
A. Adaptive immunity
B. Antibodies
C. Innate immunity
D. T cells .
Answer Explanation
Innate immunity represents the first line of defense to an intruding pathogen.
The innate immune system is a series of nonspecific defenses that make up the innate immune system.
These defenses are not directed against any one pathogen but instead provide a guard against all infection.
Choice A is incorrect because adaptive immunity is activated when pathogens are able to bypass innate immune defenses.
Choice B is incorrect because antibodies are part of the adaptive immune system and are produced by B cells.
Choice D is incorrect because T cells are part of the adaptive immune system and assist B cells or directly kill infected cells.
