ATI TEAS Science

Correct Answer: D

Rationale: During meiosis, a parent cell undergoes two rounds of cell division resulting in the formation of four daughter cells. 1. In the first division (meiosis I), homologous chromosomes separate, resulting in two daughter cells with half the number of chromosomes as the parent cell. 2. In the second division (meiosis II), sister chromatids separate, producing a total of four daughter cells, each with a haploid set of chromosomes. Therefore, the correct answer is D: Four. Choices A, B, and C are incorrect because meiosis specifically leads to the formation of four daughter cells, not one, two, or three.

Correct Answer: D

Rationale: The correct answer is D because the autonomic nervous system (ANS) indeed contains both parasympathetic and sympathetic nerves. The ANS regulates involuntary functions such as heart rate, digestion, and respiratory rate. A: While A is partially correct, it does not encompass the full scope of the ANS functions. B: B is incorrect as the ANS primarily consists of efferent neurons that carry motor signals from the central nervous system to target organs. C: C is incorrect as the ANS consists of efferent neurons that carry signals away from the central nervous system to target organs, not sensory neurons.

Correct Answer: A

Rationale: The correct answer is A: The smallest amount of stimulus required for an individual to feel a sensation. The sensory threshold refers to the minimum level of stimulation needed for an individual to detect a particular sensation. This threshold varies from person to person and can be influenced by factors such as sensitivity and attention. Choice B is incorrect as it specifically relates to feeling pain, which is a different sensory experience. Choice C is incorrect as it refers to a response to a stimulus (movement) rather than the detection of sensation. Choice D is incorrect as it describes the origin of the stimulus rather than the threshold for sensation detection.

Correct Answer: A

Rationale: The correct answer is A: DNA mutation. An alteration in the normal gene sequence is referred to as a mutation, which can result from changes in the DNA sequence. Mutations can lead to variations in genetic information. Gene migration (B) refers to the movement of genes between populations. Polygenic inheritance (C) involves the contribution of multiple genes to a trait. Incomplete dominance (D) is a genetic pattern where the phenotype of a heterozygous individual is intermediate between the two homozygous phenotypes.

Correct Answer: C

Rationale: The correct answer is C because sinuses warm, humidify, and filter air before it reaches the lungs, improving respiratory efficiency. Sinuses have mucous membranes that trap particles and pathogens, preventing them from entering the respiratory system. This process helps to protect the lungs and maintain their health. Choices A, B, and D are incorrect because sinuses do not primarily trap pathogens, direct air down the trachea, or sweep away pathogens towards the top of the trachea.