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 .
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.
Therefore, the Correct Answer is C.
More Questions on TEAS 7 Science
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Q #1: During the menstrual cycle, which structure in the ovary produces progesterone to prepare the endometrium for potential implantation?
A. Corpus luteum.
B. Fimbriae
C. Follicle
D. Ovarian ligament.
Answer Explanation
Corpus luteum.
During the menstrual cycle, the corpus luteum in the ovary produces progesterone to prepare the endometrium for potential implantation.
Choice B is incorrect because fimbriae are finger-like projections at the end of the fallopian tubes that help guide the egg into the tube.
Choice C is incorrect because a follicle is a sac in the ovary that contains an immature egg.
Choice D is incorrect because the ovarian ligament is a fibrous band of tissue that connects the ovary to the uterus.
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Q #2: Which type of bond is responsible for the unique properties of water and plays a crucial role in the structure of DNA and proteins?
A. Hydrogen bonds.
B. Covalent bonds.
C. Ionic bonds.
D. Van der Waals forces.
Answer Explanation
The correct answer is choice A. Hydrogen bonds.
Hydrogen bonds are responsible for the unique properties of water and play a crucial role in the structure of DNA and proteins.
Hydrogen bonds are weak electrostatic attractions between a hydrogen atom covalently bonded to an electronegative atom and another electronegative atom.
Choice B.
Covalent bonds is incorrect because covalent bonds are strong chemical bonds formed by the sharing of electrons between two atoms.
Choice C.
Ionic bonds is incorrect because ionic bonds are chemical bonds formed by the transfer of electrons from one atom to another, resulting in the formation of ions.
Choice D.
Van der Waals forces is incorrect because Van der Waals forces are weak intermolecular forces that arise from temporary dipoles induced in atoms or molecules.
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Q #3: In which type of tissue would you find a fibrous protein that provides strength and protection to the body, particularly in the skin, hair, and nails?
A. Keratin
B. Collagen
C. Elastin
D. Actin
Answer Explanation
The correct answer is choice A. Keratin.
Keratin is a fibrous protein that provides strength and protection to the body, particularly in the skin, hair, and nails.
It is found in epithelial tissue, which covers the body’s surface and lines its internal organs and cavities.
Choice B.
Collagen is incorrect because collagen is a fibrous protein that provides strength and support to connective tissues such as tendons, ligaments, and cartilage.
Choice C.
Elastin is incorrect because elastin is a protein that provides elasticity to tissues such as skin and blood vessels.
Choice D.
Actin is incorrect because actin is a protein that plays a role in muscle contraction and cell movement.
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Q #4: What is the purpose of using PCR (polymerase chain reaction) in the laboratory?
A. To separate DNA fragments by size.
B. To amplify specific regions of DNA.
C. To sequence DNA fragments.
D. To analyze protein expression levels.
Answer Explanation
The correct answer is choice B.
To amplify specific regions of DNA.
PCR (polymerase chain reaction) is a laboratory technique used to make many copies of a specific region of DNA.
The goal of PCR is to make enough of the target DNA region that it can be analyzed or used in some other way.
PCR has many research and practical applications, including DNA cloning, medical diagnostics, and forensic analysis of DNA.
Choice A is incorrect because PCR does not separate DNA fragments by size. Choice C is incorrect because PCR does not sequence DNA fragments.
Choice D is incorrect because PCR does not analyze protein expression levels.
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Q #5: 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 #6: Which of the following structures in the nephron is responsible for reabsorbing ions, water and nutrients?
A. Distal tubule
B. Proximal tubule
C. Glomerulus
D. Loop of Henle
Answer Explanation
Proximal tubule
The proximal tubule is responsible for reabsorbing all the nutrients and most of the water.
Choice A is incorrect because the distal tubule is not primarily responsible for reabsorbing ions, water and nutrients.
Choice C is incorrect because the glomerulus is responsible for filtering fluid and solutes out of the blood to form a glomerular filtrate.
Choice D is incorrect because the Loop of Henle is not primarily responsible for reabsorbing ions, water and nutrients.
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Q #7: Which cytotoxic lymphocyte granules contain serine proteases that induce apoptosis in target cells?.
A. Perforins.
B. Cytokines.
C. Granzymes.
D. Interferons.
Answer Explanation
Granzymes.
Granzymes are a family of serine proteases that are stored in and secreted from the cytotoxic granules of cytotoxic T lymphocytes (CTL) and natural killer (NK) cells.
They work in synergy with perforin, a pore-forming toxin, to induce apoptosis in target cells.
Perforin is necessary for the delivery of granzyme B to the target cell cytosol where caspase-dependent and -independent pathways to apoptosis are activated.
Perforins (choice A) are pore-forming toxins that work in synergy with granzymes to induce apoptosis in target cells.
Cytokines (choice B) are signaling molecules that regulate immune responses but do not directly induce apoptosis in target cells.
Interferons (choice D) are a type of cytokine that play a role in immune responses but do not directly induce apoptosis in target cells.
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Q #8: Which process involves the fusion of male and female gametes resulting in the formation of a zygote?
A. Oogenesis.
B. Fertilization.
C. Meiosis.
D. Mitosis.
Answer Explanation
Fertilization.
Fertilization is the process by which male and female gametes fuse to form a zygote.
Oogenesis (choice A) is the process by which female gametes, or eggs, are produced.
Meiosis (choice C) is a type of cell division that results in the formation of gametes.
Mitosis (choice D) is a type of cell division that results in the formation of two identical daughter cells.
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Q #9: 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 #10: A patient with chronic kidney disease is at risk for developing which of the following electrolyte imbalances?
A. Decrease in the concentration of calcium in the glomerulus.
B. Increase in the concentration of potassium in the blood.
C. Decrease in the concentration of sodium in the blood.
D. Increase in the concentration of magnesium in the blood.
Answer Explanation
The correct answer is choice B.
A patient with chronic kidney disease is at risk for developing an increase in the concentration of potassium in the blood.
The kidneys play a pivotal role in the regulation of electrolyte balance.
With progressive loss of kidney function, derangements in electrolytes inevitably occur and contribute to poor patient outcomes123.
Choice A is incorrect because calcium concentration is not regulated in the glomerulus.
Choice C is incorrect because chronic kidney disease can result in either an increase or decrease in sodium concentration in the blood.
Choice D is incorrect because chronic kidney disease does not necessarily result in an increase in magnesium concentration in the blood.
