TEAS 7 science quizlet

Correct Answer: C

Rationale: External respiration is the correct term for the process of exchanging gases (oxygen and carbon dioxide) between the blood and the tissues. It specifically refers to the exchange of gases that occurs in the lungs, where oxygen is absorbed into the bloodstream and carbon dioxide is released from the bloodstream to be exhaled. Inhalation and exhalation, choices A and B, are phases of the breathing process that involve the intake and expulsion of air into and out of the lungs, respectively. Internal respiration, choice D, is the process of gas exchange that happens at the cellular level between the blood and body tissues, not between the blood and the lungs or tissues as in external respiration. Therefore, external respiration is the most appropriate term for the described gas exchange process in the question.

Correct Answer: B

Rationale: The correct answer is B. Isometric contractions occur when the muscle generates tension without changing its length, while isotonic contractions involve the muscle changing length to move a load. In isotonic contractions, the muscle shortens to move a load, whereas in isometric contractions, the muscle contracts to hold a position without movement. Choice A is incorrect because isometric contractions do not involve movement, while choice C is incorrect as isotonic contractions typically require more energy due to movement. Choice D is incorrect because the type of muscle involved (smooth or skeletal) is not the defining factor between isometric and isotonic contractions.

Correct Answer: B

Rationale: The correct answer is B, Chlorine. Chlorine is the element present in household bleach that provides disinfectant properties due to its oxidizing ability. Chlorine is effective in killing bacteria and other microorganisms. Sodium (Choice A) is a component of common table salt and not the active disinfectant in bleach. Fluorine (Choice C) is not typically found in household bleach but is used in fluoride products. Iodine (Choice D) is used as a disinfectant in some contexts but is not the primary element in household bleach.

Correct Answer: A

Rationale: When a wave passes from one medium to another with the same speed, its frequency remains unchanged. Frequency is a characteristic of the source of the wave and does not depend on the medium through which the wave is traveling. Wavelength and speed of the wave can change when passing from one medium to another, but frequency remains constant. This is because the frequency of a wave is determined by the source that produces it, and as long as the speed remains constant, the frequency will not be altered. Amplitude, on the other hand, can change based on factors like energy loss or gain, but it is not a property that remains constant when a wave moves between different mediums with the same speed. Speed, although important for the wave's propagation, is not the property that remains unchanged when the wave transitions between mediums with the same speed. Therefore, the correct answer is frequency.

Correct Answer: D

Rationale: When a wave crosses a boundary between two different media, its speed is the property that remains constant. This is due to the principle of conservation of energy. While the frequency and wavelength of a wave may change as it moves from one medium to another, the speed of the wave remains constant. This phenomenon is a result of the wave adjusting its frequency and wavelength to maintain a consistent speed in different media. Therefore, choices A, B, and C are incorrect. Frequency and wavelength may change when a wave moves across media, and amplitude may also be affected by the medium, but the speed of the wave will remain constant.