During protein synthesis, what process uses an RNA strand to produce a complementary strand of DNA?

Correct Answer: A

Rationale: The correct answer is 'Transcription.' During transcription, an RNA strand is used to produce a complementary strand of DNA. This process is essential for converting the genetic information stored in DNA into RNA. Choice B, 'Translation,' is incorrect as it involves the synthesis of proteins from mRNA. Choice C, 'Transfer synthesis,' is not a recognized term in molecular biology. Choice D, 'Codon synthesis,' is also incorrect as it does not refer to the process of using an RNA strand to produce a complementary DNA strand.

Correct Answer: D

Rationale: The correct answer is 'D: DNA.' DNA is not directly involved in translation, which is the process of synthesizing proteins from mRNA. tRNA carries amino acids to the ribosome, mRNA provides the template for protein synthesis, and ribosomes are the cellular machinery where translation occurs. DNA's main role is in transcription, where it serves as the template for mRNA synthesis, not in translation.

Correct Answer: A

Rationale: The correct answer is 'species.' In binomial nomenclature, the second part of an organism's scientific name represents its species. The species name is a unique identifier within the genus and helps differentiate between different organisms within the same genus. Choices B, C, and D are incorrect. Phylum is a taxonomic rank higher than species, population refers to a group of organisms of the same species living in the same area, and kingdom is a taxonomic rank higher than genus.

Correct Answer: C

Rationale: The correct answer is C: Synthesize proteins. Ribosomes are responsible for protein synthesis by linking amino acids together. Choice A is incorrect because ribosomes do not break down cellular waste. Choice B is incorrect as ribosomes do not organize cellular division. Choice D is incorrect because ribosomes do not provide cellular structure.

Correct Answer: C

Rationale: The correct answer is 'Selectively permeable.' The cell membrane's bilayer structure allows it to be selectively permeable, meaning it can control the passage of substances. This property enables the membrane to regulate the entry and exit of specific molecules, ions, and other substances. Choice A, 'Impermeable,' is incorrect as the cell membrane is not completely impermeable and does allow certain substances to pass through. Choice B, 'Permeable,' is also incorrect as it does not address the selective nature of the membrane. Choice D, 'Selectively impermeable,' is a contradictory term and does not accurately describe the cell membrane's function.

Correct Answer: C

Rationale: The correct answer is 'Fermentation and cellular respiration.' Fermentation is an anaerobic catabolic process that occurs in the absence of oxygen, producing limited amounts of ATP. Cellular respiration, on the other hand, is the aerobic catabolic pathway that occurs in the presence of oxygen and is the most efficient way of producing ATP. Choices A, B, and D are incorrect because internal respiration, external respiration, and anaerobic respiration are not the correct pathways leading to cellular energy production.

Correct Answer: D

Rationale: DNA is important for the metabolic activities of the cell because it controls the synthesis of enzymes. Enzymes are essential for catalyzing metabolic reactions in the cell. Choices A, B, and C are incorrect because DNA is not directly involved in cellular mitosis, cell wall stability, or glucose absorption.

Correct Answer: C

Rationale: Sugar and phosphate are indeed connected by covalent bonds in DNA. Covalent bonds involve the sharing of electrons between atoms, which is essential for forming the backbone of the DNA molecule. Hydrogen bonds (Choice A) are important in holding the nitrogenous bases together in the DNA double helix but do not connect sugar and phosphate. Ionic bonds (Choice B) involve the transfer of electrons between atoms and are not the primary bond connecting sugar and phosphate in DNA. 'Overt' (Choice D) is not a type of chemical bond and is an incorrect distractor.

Correct Answer: B

Rationale: The correct answer is B: Ribosome. Ribosomes are responsible for organizing protein synthesis by assembling amino acids. They are the cellular machinery where proteins are synthesized. The other choices, such as the nucleus, lysosome, and vacuole, do not directly participate in protein synthesis. The nucleus contains DNA and controls cell activities, the lysosome is involved in digestion and waste removal, and the vacuole is responsible for storage and maintaining cell turgor pressure.