Which of the following is NOT an element of the respiratory system?
- A. Ribs
- B. Trachea
- C. Diaphragm
- D. Alveoli
Correct Answer: A
Rationale: The correct answer is A: Ribs. The ribs are part of the skeletal system, providing structure and protection to the thoracic cavity. The trachea, diaphragm, and alveoli are all essential components of the respiratory system. The trachea carries air to and from the lungs, the diaphragm aids in breathing by contracting and relaxing to change the volume of the thoracic cavity, and the alveoli are tiny air sacs where gas exchange occurs in the lungs. Therefore, ribs do not play a direct role in the respiratory process and are not considered a part of the respiratory system.
You may also like to solve these questions
A substance is only considered acidic if it has a pH less than what?
- A. 12
- B. 9
- C. 7
- D. 4
Correct Answer: C
Rationale: A substance is considered acidic if its pH is less than 7. pH values below 7 indicate acidity, while pH values above 7 indicate alkalinity or basicity. Substances with a pH less than 7 are categorized as acidic, not above it. Therefore, a substance is classified as acidic if its pH is less than 7, making choice C the correct answer. Choices A, B, and D are incorrect because a pH of 12, 9, and 4, respectively, are all above 7, and therefore not indicative of acidity.
Mrs. Jones's class is conducting an experiment. They will substitute artificial sweetener for sugar in a cookie recipe to determine the effect on the overall color of the baked cookies. Which of the following should be included in the instructions for the experiment?
- A. When preparing the batch that includes artificial sweetener, 20% more water should be included.
- B. The bake temperature should be decreased from 425°F to 400°F.
- C. The batch with artificial sweetener should be baked on a stainless steel sheet.
- D. Ingredient proportions, bake time, bake temperature, and cookie sheet material should all be kept the same between the two batches.
Correct Answer: D
Rationale: To ensure a valid comparison and isolate the impact of the artificial sweetener, the experiment should maintain consistency in all factors except the sugar substitution. By keeping ingredient proportions, bake time, bake temperature, and cookie sheet material the same, any observed differences in the color of the cookies can be attributed to the artificial sweetener rather than other variables. Choices A, B, and C introduce additional variables that could confound the results. Choice A would alter the consistency of the recipe by adjusting the water content, Choice B would introduce a change in baking temperature which could affect the outcome, and Choice C suggests a change in the type of baking sheet used, potentially impacting the baking process and results. Therefore, maintaining consistency in all other factors except for the sugar substitution is crucial for a reliable experiment.
Which of the following best describes one of the roles of RNA?
- A. Manufacturing the proteins needed from DNA
- B. Creating the bonds between the elements that make up DNA
- C. Sending messages about the correct sequence of proteins in DNA
- D. Forming the identifiable double helix shape of DNA
Correct Answer: C
Rationale: The correct answer is C. RNA serves as a messenger that carries instructions from DNA for protein synthesis. It does not manufacture proteins directly from DNA (choice A), create bonds within DNA (choice B), or form the double helix structure of DNA (choice D). Therefore, the primary role of RNA is to convey information about the correct sequence of proteins to be synthesized based on the DNA sequences it receives.
Based on the following evidence, what is the most likely reason that spoiled food left out in the open often contains fly larvae?
- A. The spoiled food evolves into fly larvae.
- B. Since the food is left out in the open, flies lay eggs in the food.
- C. Fly larvae are spontaneously generated by the spoiled food.
- D. People only imagine they see fly larvae in the spoiled food.
Correct Answer: B
Rationale: The correct answer is B. Flies laying eggs in the food when it is left exposed to the air is a common occurrence and a logical explanation for the presence of fly larvae in spoiled food. Choice A is incorrect as food cannot evolve into fly larvae; fly larvae come from eggs laid by flies. Choice C is incorrect as fly larvae do not spontaneously generate from spoiled food but rather develop from eggs laid by flies. Choice D is incorrect as the presence of fly larvae in spoiled food is a real phenomenon, not merely imagined by people.
How do hydrogen bonds in water affect its characteristics?
- A. Hydrogen bonds are not polar enough to attract non-polar molecules.
- B. Hydrogen bonds cause water to be less dense when it is a solid than when it is a liquid.
- C. Hydrogen bonds cause water to have high surface tension, allowing some organisms to move across it.
- D. Hydrogen bonds cause water to be a good solvent.
Correct Answer: C
Rationale: Hydrogen bonds in water contribute to its high surface tension, enabling some organisms to move across the water's surface. This property is essential for certain insects and small animals that rely on surface tension to move or stay afloat on water. Choice A is incorrect because hydrogen bonds are polar and can attract polar and other charged molecules. Choice B is incorrect as hydrogen bonds make ice less dense than liquid water, which is a unique property. Choice D is incorrect as the ability of water to act as a good solvent is primarily due to its polarity, not just hydrogen bonding.