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
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.
Therefore, the Correct Answer is A.
More Questions on TEAS 7 Science
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Q #1: 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 #2: Which type of lymphocyte is capable of killing tumor cells and infected cells without prior sensitization?.
A. Helper T cells.
B. B cells.
C. Natural killer cells.
D. Cytotoxic T cells .
Answer Explanation
Natural killer cells.
Natural killer (NK) cells are large granular lymphocytes that are capable of destroying cells infected by viruses or bacteria and susceptible tumor cells without prior sensitization and restriction by MHC antigens.
Helper T cells (choice A) are a type of white blood cell that helps other immune cells respond to infections but do not directly kill infected or tumor cells.
B cells (choice B) are a type of white blood cell that produces antibodies to fight infections but do not directly kill infected or tumor cells.
Cytotoxic T cells (choice D) are a type of white blood cell that can kill infected or tumor cells but require prior sensitization to do so.
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Q #3: 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 #4: 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 #5: 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 #6: 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.
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Q #7: What is hydrogen bonding?
A. The attraction between the relatively positive areas of one molecule and the relatively negative areas of another molecule.
B. The repulsion between the positive and negative charges of two molecules.
C. The attraction between two nonpolar molecules.
D. The attraction between two ionic molecules.
Answer Explanation
Hydrogen bonding is an interaction involving a hydrogen atom located between a pair of other atoms having a high affinity for electrons.
One atom of the pair (the donor), generally a fluorine, nitrogen, or oxygen atom, is covalently bonded to a hydrogen atom, whose electrons it shares unequally; its high electron affinity causes the hydrogen to take on a slight positive charge.
The other atom of the pair (the acceptor), also typically F, N, or O, has an unshared electron pair, which gives it a slight negative charge.
Mainly through electrostatic attraction, the donor atom effectively shares its hydrogen with the acceptor atom, forming a bond.
Choice B) The repulsion between the positive and negative charges of two molecules is incorrect because hydrogen bonding involves attraction, not repulsion.
Choice C) The attraction between two nonpolar molecules is incorrect because hydrogen bonding involves polar molecules.
Choice D) The attraction between two ionic molecules is incorrect because hydrogen bonding involves polar molecules and not ionic molecules.
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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 of the following is a potential complication of carbon monoxide poisoning?
A. Conversion to carbon monoxide.
B. Formation of carboxyhemoglobin.
C. Increased production of red blood cells.
D. Decreased pulmonary function.
Answer Explanation
Formation of carboxyhemoglobin.
Carbon monoxide binds to the hemoglobin to create a molecule called carboxyhemoglobin (COHb), which interferes with the body’s ability to transport and use oxygen, especially in the brain.
Choice A is incorrect because carbon monoxide poisoning occurs when carbon monoxide builds up in your bloodstream.
Choice C is incorrect because carbon monoxide poisoning does not increase the production of red blood cells.
Choice D is incorrect because decreased pulmonary function is not a potential complication of carbon monoxide poisoning.
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Q #10: What is the relationship between viruses and their host cells during replication?
A. Viruses use the host’s replication processes to produce progeny virus particles.
B. Viruses divide inside the host cell to produce progeny virus particles.
C. Viruses have their own replication processes and do not need the host cell.
D. Viruses infect the host cell and destroy it completely.
Answer Explanation
Viruses use the host’s replication processes to produce progeny virus particles.
Viruses are obligate intracellular parasites, meaning that they require a host cell to replicate.
They hijack the host cell’s machinery to produce new virus particles.
Choice B is incorrect because viruses do not divide inside the host cell.
Instead, they use the host cell’s machinery to produce new virus particles.
Choice C is incorrect because viruses do not have their own replication processes and rely on the host cell for replication.
Choice D is incorrect because while some viruses may destroy the host cell during replication, this is not always the case and is not the primary relationship between viruses and their host cells during replication.
