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.
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.
Therefore, the Correct Answer is B.
More Questions on TEAS 7 Science
-
Q #1: Which of the following hormones is responsible for regulating the body's metabolism and energy levels?
A. Estrogen
B. Progestin
C. Thyroxine
D. Androgen
Answer Explanation
The correct answer is choice C. Thyroxine.
Thyroxine (T4) is a hormone produced by the thyroid gland that controls your body’s metabolism, the process in which your body transforms the food you eat into energy.
Choice A, Estrogen, is not the correct answer because it is a hormone responsible for the development of female secondary sexual characteristics.
Choice B, Progestin, is not the correct answer because it is a synthetic form of progesterone used in hormonal birth control and hormone replacement therapy.
Choice D, Androgen, is not the correct answer because it is a hormone responsible for the development of male secondary sexual characteristics.
-
Q #2: A nurse is reviewing the results of a patient’s DNA sequencing test, which was performed to diagnose a genetic disorder. The nurse notices that the patient has a mutation in one of the bases of the DNA. Which of the following is the correct term for this type of mutation?
A. Deletion
B. Insertion
C. Substitution
D. Inversion
Answer Explanation
The correct answer is choice C. Substitution.
A substitution mutation is a type of point mutation where one base in the DNA sequence is replaced by another base.
Choice A is incorrect because a deletion mutation occurs when one or more bases are removed from the DNA sequence.
Choice B is incorrect because an insertion mutation occurs when one or more bases are added to the DNA sequence.
Choice D is incorrect because an inversion mutation occurs when a segment of DNA is reversed within the chromosome.
-
Q #3: 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.
