1. A study finds a link between increased screen time and lower academic performance. What additional information would be most helpful in interpreting this finding?

A. The average socioeconomic status of the study participants.
B. The specific types of screen activities participants engaged in.
C. Whether the students had access to healthy meals and snacks.
D. The participants' ages and grade levels.

Correct answer: B

Rationale: Knowing the specific types of screen activities participants engaged in would provide crucial context for interpreting the link between increased screen time and lower academic performance. For example, if the majority of screen time was spent on educational apps or programs, the impact on academic performance may differ compared to if the screen time was mostly spent on social media or gaming. Understanding the nature of screen activities can help determine the potential mechanisms behind the observed relationship.

2. Which conjunction best joins the following sentence: "She loves animals, ____ she volunteers at the shelter."

A. because
B. therefore
C. so
D. and

Correct answer: D

Rationale: "And" simply adds information about her love for animals without implying cause or effect.

3. Differentiate between gene therapy and genetic engineering in the context of human intervention.

A. Gene therapy aims to modify existing genes within body cells, while genetic engineering manipulates genes in embryos to be passed on to offspring.
B. Gene therapy focuses on treating genetic diseases, while genetic engineering enhances desirable traits or eliminates undesirable ones.
C. Both involve directly altering the DNA sequence, but gene therapy targets somatic cells and genetic engineering modifies germline cells.
D. There is no fundamental difference; both terms are synonymous.

Correct answer: B

Rationale: Rationale: A) Incorrect. Gene therapy does aim to modify existing genes within body cells, but genetic engineering does not necessarily manipulate genes in embryos to be passed on to offspring. Genetic engineering can involve modifying genes in any type of cell, not just embryos. B) Correct. Gene therapy is a medical intervention that aims to treat genetic diseases by correcting or replacing faulty genes within an individual's body cells. On the other hand, genetic engineering involves modifying genes to enhance specific traits or eliminate undesirable ones, often in the context of agriculture or biotechnology. C) Incorrect. While both gene therapy and genetic engineering involve altering DNA sequences, the distinction lies in the target cells. Gene therapy targets somatic cells (non-reproductive cells), while genetic engineering typically involves modifying germline cells (reproductive cells that can pass on genetic changes to offspring). D) Incorrect. There is

4. During vigorous exercise, the respiratory rate increases to:

A. Meet the increased demand for oxygen in working muscles
B. Eliminate excess carbon dioxide more slowly
C. Conserve energy for physical activity
D. Decrease the amount of oxygen delivered to the body

Correct answer: A

Rationale: During vigorous exercise, the respiratory rate increases to meet the increased demand for oxygen in working muscles. When we exercise vigorously, our muscles require more oxygen to produce energy through aerobic metabolism. Increasing the respiratory rate allows more oxygen to be taken in and transported to the muscles via the bloodstream to support this increased demand. Option A is correct because it accurately reflects the physiological response of the respiratory system to vigorous exercise, ensuring that working muscles receive sufficient oxygen for optimal performance.

5. What is the function of ribosomal RNA (rRNA)?

A. Carries amino acids to the ribosomes
B. Reads th(a) Carries amino acids to the ribosomes: This is the function of transfer RNA (tRNA), not ribosomal RNA. (b) Reads the genetic code on mRNA: This is the function of the ribosomes as a whole, not just the ribosomal RNA. (d) Controls the rate of protein synthesis: This is a more complex process involving various factors, not solely ribosomal RNA. e genetic code on mRNA
C. Forms the structural framework of ribosomes
D. Controls the rate of protein synthesis

Correct answer: C

Rationale: Rationale: Ribosomal RNA (rRNA) plays a crucial role in forming the structural framework of ribosomes, which are the cellular organelles responsible for protein synthesis. Ribosomes consist of both protein and rRNA components, with rRNA providing the structural support necessary for the ribosome to function properly. This structural framework allows the ribosome to interact with messenger RNA (mRNA) and transfer RNA (tRNA) during the process of translation, where the genetic information encoded in mRNA is used to assemble proteins from amino acids. Therefore, the primary function of rRNA is to contribute to the structure and function of ribosomes, rather than directly carrying amino acids, reading the genetic code, or controlling the rate of protein synthesis.

6. Where does most of the chemical digestion and absorption of nutrients occur?

A. Mouth
B. Stomach
C. Small intestine
D. Large intestine

Correct answer: C

Rationale: Rationale: The small intestine is where most of the chemical digestion and absorption of nutrients occur in the digestive system. This is because the small intestine is lined with villi and microvilli, which increase the surface area available for absorption. Enzymes secreted by the pancreas and bile from the liver aid in breaking down food into smaller molecules that can be absorbed through the intestinal wall into the bloodstream. The stomach primarily functions in the mechanical breakdown of food and the initial stages of protein digestion, while the large intestine is mainly responsible for absorbing water and electrolytes from the remaining indigestible food particles. The mouth is involved in the initial mechanical breakdown of food through chewing and some chemical digestion of carbohydrates by salivary enzymes, but the majority of nutrient absorption occurs in the small intestine.