Nokea
Which of the following organic molecules contains both an amine and a carboxyl group?
- A. Lipids
- B. Cellulose
- C. Chitin
- D. Proteins
Correct Answer: D
Rationale: Proteins are composed of amino acids, which contain both an amine (NH2) and a carboxyl (COOH) functional group. The amine group is found at one end of the amino acid molecule, while the carboxyl group is located at the other end. When amino acids join together through peptide bonds, the amine of one amino acid reacts with the carboxyl group of another, forming a protein chain. Therefore, the correct answer is proteins.
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If a portion of a strand of DNA bases reads 5' AGCTAGCGT 3', what would the sequence of bases on the complementary strand read?
- A. 3' AGCTAGCGT 5'
- B. 5' UCGAUCGCA 3'
- C. 3' TCGATCGCA 5'
- D. 5' TCGUTCGCU 3'
Correct Answer: C
Rationale: To determine the sequence of bases on the complementary DNA strand, you must apply the base pairing rules: adenine (A) pairs with thymine (T) and cytosine (C) pairs with guanine (G). The given original sequence is 5' AGCTAGCGT 3'. Consequently, the complementary strand will read 3' TCGATCGCA 5'. Each base on one strand corresponds with its complementary base on the other strand, forming a sequence that complements the original one.
htmlspecialchars(The mitochondrial inner membrane carries out the same functions in cellular respiration as the ......... membrane of chloroplasts in photosynthesis. Which of the following correctly completes the sentence above?)
- A. htmlspecialchars(Epithelial)
- B. htmlspecialchars(Nuclear)
- C. htmlspecialchars(Thylakoid)
- D. htmlspecialchars(Tonoplast)
Correct Answer: htmlspecialchars(C)
Rationale: htmlspecialchars(The correct answer is C - Thylakoid. The inner membrane of mitochondria is where cellular respiration occurs, just as the thylakoid membrane in chloroplasts is where photosynthesis takes place. These membranes are essential for energy production in their respective processes. Understanding the role of these membranes is crucial in comprehending how cells generate energy through cellular respiration and photosynthesis.)
Which of the following characteristics of water helps explain why coastal areas experience less dramatic temperature changes during the day than more inland areas?
- A. Water's adhesive properties prevent evaporation.
- B. Water is a versatile solvent.
- C. Water has a high specific heat capacity.
- D. Water forms covalent bonds with other water molecules.
Correct Answer: C
Rationale: The correct answer is C. Water has a high specific heat capacity, meaning it can absorb and store a large amount of heat energy before its temperature rises significantly. This characteristic allows water to moderate temperature changes by absorbing heat during the day and releasing it slowly at night, resulting in less dramatic temperature fluctuations along coastal areas compared to inland areas. Water's adhesive properties (choice A) do not directly contribute to moderating temperature changes. While being a versatile solvent (choice B) is a notable property of water, it is not the primary reason for the specific temperature moderation observed in coastal areas. Water forming covalent bonds with other water molecules (choice D) is more related to its molecular structure rather than its role in temperature moderation.
Blockage and inflammation of which of the following structures most often leads to facial acne?
- A. Lacrimal glands
- B. Sebaceous glands
- C. Ceruminous glands
- D. Sudoriferous glands
Correct Answer: B
Rationale: Sebaceous glands are responsible for producing sebum, an oily substance that can clog pores when overproduced or combined with dead skin cells. This blockage promotes the growth of acne-causing bacteria and leads to inflammation. The other glands listed in the choices do not play a significant role in the development of facial acne. Ceruminous glands produce earwax (cerumen) to protect the ear canal, sudoriferous glands produce sweat to regulate body temperature, and lacrimal glands produce tears to lubricate and protect the eyes.
In a study that found two processes, process A and process B, to be correlated, which of the following statements is true for these processes?
- A. The study cannot indicate whether processes A and B have a negative relationship.
- B. The study does not indicate a causal relationship between the processes.
- C. The study cannot indicate whether processes A and B have a positive relationship.
- D. The study indicates that process A causes process B.
Correct Answer: B
Rationale: When two processes are found to be correlated, it means that they are related in some way, but correlation does not imply causation. The study establishes a statistical relationship between process A and process B, but it does not prove that one causes the other. Therefore, the study does not indicate a causal relationship between the processes. Choice B is the correct answer as it accurately reflects this limitation of the study's findings.