dna and rna are both subunits of which biological molecule
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Biology Practice Test

1. DNA and RNA are both subunits of which biological molecule?

Correct answer: A

Rationale: The correct answer is A: Nucleic acids. DNA and RNA are both types of nucleic acids, which are fundamental biological molecules responsible for storing and transmitting genetic information. Choice B, Proteins, are not subunits of DNA and RNA but are composed of amino acids. Carbohydrates, choice C, are another type of biological molecule involved in energy storage and structural support, not subunits of DNA and RNA. Lipids, choice D, are a diverse group of molecules that include fats, oils, and steroids, but they are not subunits of DNA and RNA.

2. Prophase is the first stage of mitosis. Which of the following best describes chromosomes during this stage?

Correct answer: D

Rationale: The correct answer is D. During prophase, the chromosomes condense and become visible as distinct structures under a microscope. Choice A is incorrect as chromosomes are not gathered on either side of the separating cell during prophase. Choice B is incorrect because chromosomes align along the metaphase plate during the subsequent stage, metaphase. Choice C is incorrect as chromosomes become attached to the spindle fibers during prometaphase, the stage following prophase.

3. In the hierarchical organizational system, which of these is the most restrictive category?

Correct answer: D

Rationale: In the biological classification hierarchy, species is the most specific level, defining individual organisms that can interbreed. While genus, class, and kingdom are also categories in the hierarchy, they are broader and encompass a wider range of organisms compared to species. Genus groups together similar species, class groups similar orders, and kingdom is the broadest category grouping together similar phyla.

4. The liver is an organ responsible for detoxifying the body of many harmful substances. You might expect the liver to contain a high amount of which of the following?

Correct answer: B

Rationale: The correct answer is B: Smooth endoplasmic reticulum. The liver contains a high amount of smooth endoplasmic reticulum because it plays a significant role in detoxification processes, such as the synthesis of detoxifying enzymes and lipids. Choice A (Rough endoplasmic reticulum) is incorrect because the rough endoplasmic reticulum is more involved in protein synthesis and processing. Choice C (Mitochondria) is incorrect as mitochondria are primarily responsible for energy production. Choice D (Lysosomes) is incorrect because lysosomes are organelles involved in intracellular digestion and waste removal, not specifically related to detoxification.

5. A molecule's specific heat is the amount of heat necessary to raise the temperature of 1 gram of that molecule by:

Correct answer: A

Rationale: The correct answer is A: 'One degree Celsius.' Specific heat is defined as the amount of heat required to raise the temperature of one gram of a substance by one degree Celsius. This property is specific to each substance and is used in various calculations involving heat and temperature changes. Choices B, C, and D are incorrect because specific heat is always measured per one degree Celsius increase in temperature for one gram of the substance, not five degrees, two degrees, or four degrees.

Similar Questions

Which of the following is the process that reduces cells originally classified as diploid to haploid?
Which organelle is responsible for the synthesis of lipids and steroid hormones?
During which stage of mitosis does the nuclear envelope begin to disappear and the chromosomes start attaching to the spindle forming along the cell's axis?
Which of the following provides support and shape to the cell?
What are the nitrogenous bases of DNA?

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