ati teas 7 science

Correct Answer: A

Rationale: The main function of lysosomes is to break down and recycle cellular waste through the process of autophagy. Lysosomes contain enzymes that break down various molecules, organelles, and pathogens. This process helps maintain cellular homeostasis and provides the cell with raw materials for new cell components. Storing carbohydrates (B) is incorrect as lysosomes do not function in this capacity. Synthesizing lipids (C) is incorrect as this is typically the role of the endoplasmic reticulum and Golgi apparatus. Transcribing DNA into mRNA (D) is incorrect as this process occurs in the nucleus by RNA polymerase.

Correct Answer: C

Rationale: The myelin sheath is derived from nervous tissue, specifically glial cells. Glial cells, also known as neuroglia, support and protect nerve cells. They produce the myelin sheath, which insulates nerve fibers and allows for faster transmission of nerve impulses. Epithelial tissue (choice A) primarily covers and lines body surfaces, muscle tissue (choice B) is responsible for movement, and connective tissue (choice D) provides support and structure to the body. None of these tissues are involved in the production of the myelin sheath, making them incorrect choices.

Correct Answer: C

Rationale: The correct answer is C: Testosterone. Testosterone is crucial for stimulating sperm production in males as it is the primary male sex hormone responsible for regulating the development of male reproductive tissues. It plays a key role in the production of sperm cells in the testes. Estrogen (A) and Progesterone (B) are female sex hormones and do not have a direct role in sperm production. Insulin (D) is a hormone that regulates blood sugar levels and is not involved in the process of sperm production.

Correct Answer: A

Rationale: The correct answer is A because polygenic inheritance refers to a trait that is influenced by multiple genes working together to produce a single phenotype. In contrast, pleiotropy occurs when a single gene has multiple effects on different traits. This distinction is crucial as it highlights the difference in the genetic basis of these phenomena. The other choices are incorrect because they either misinterpret the definitions of polygenic inheritance and pleiotropy (B and C) or provide vague statements without accurately distinguishing between the two concepts (D). The key to selecting the correct answer lies in understanding the fundamental genetic mechanisms underlying polygenic inheritance and pleiotropy.

Correct Answer: C

Rationale: The correct answer is C: Polypeptide. Translation is the process in which mRNA is decoded by ribosomes to synthesize a specific polypeptide. During translation, transfer RNA (tRNA) molecules bring specific amino acids to the ribosome based on the mRNA codons, and these amino acids are joined together to form a polypeptide chain. The other choices are incorrect because translation does not result in the production of DNA (A), lipids (B), or carbohydrates (D). Translation specifically involves the synthesis of polypeptides, making choice C the correct answer.