Practice Science TEAS Test

Correct Answer: D

Rationale: Step-by-step rationale: 1. A: The atrioventricular valves lie between the atria and the ventricles - This is true for both the tricuspid valve (right side) and the mitral valve (left side). 2. B: The pulmonary semilunar valve lies between the right ventricle and the pulmonary trunk - This is accurate, as the pulmonary semilunar valve separates the right ventricle from the pulmonary artery. 3. C: The atrioventricular valves prevent backflow into the atria when the ventricles contract - This is true as the AV valves close to prevent backflow during ventricular contraction. 4. Therefore, the correct answer is D, as all the statements are correct and accurately describe heart valve anatomy and function.

Correct Answer: B

Rationale: The correct answer is B: Gene. A gene is a smaller unit of genetic information than a chromosome. Chromosomes contain many genes, so they are larger in scale. The genome (option A) refers to the complete set of an organism's genetic material, which includes all the chromosomes. DNA (option C) is the genetic material that makes up chromosomes and genes. Option D is incorrect because while all the listed choices are related to genetics, genes are specifically smaller than chromosomes.

Correct Answer: B

Rationale: The correct answer is B: Semicircular canals. These structures are filled with fluid and lined with tiny hair cells that detect movement and changes in head position, helping maintain balance. The other choices are incorrect because: A: Cochlea is responsible for hearing, not balance. C: Eardrum helps transmit sound vibrations, but not related to balance. D: Auditory nerve carries signals from the ear to the brain for hearing, not balance.

Correct Answer: C

Rationale: The correct answer is C because DNA is indeed read 5' to 3', not 3' to 5'. This directionality is essential for DNA replication and protein synthesis. Choice A is correct as DNA contains A, T, C, G nucleotides and is read 5' to 3'. Choice B is correct as DNA carries genetic information and forms chromosomes with proteins. Choice D is correct as DNA is double-stranded with hydrogen bonds holding the two strands together.

Correct Answer: B

Rationale: The correct order of the layers of the epidermis from most superficial to deepest is: S. corneum, S. lucidum, S. granulosum, S. spinosum, S. basale (Choice B). This is because the outermost layer is the stratum corneum, followed by the stratum lucidum, then the stratum granulosum, stratum spinosum, and finally the stratum basale which is the deepest layer where new skin cells are produced. Choices A, C, and D do not follow this correct progression and therefore are incorrect.