1. Which of the following questions is NOT appropriate for scientific investigation?

A. How can we reduce greenhouse gas emissions?
B. Is there intelligent life beyond Earth?
C. What is the meaning of life?
D. Does free will exist?

Correct answer: C

Rationale: Science deals with observable, measurable phenomena using evidence-based methods. Questions about subjective experiences and abstract concepts like meaning fall outside the realm of scientific inquiry.

2. Why are isotopes of the same element chemically similar?

A. They have the same number of protons.
B. They have the same number of electrons.
C. Their chemical properties are identical.
D. They share the same electron configuration.

Correct answer: A

Rationale: They have the same number of protons. This determines the element's identity and its interactions with other elements, leading to similar chemical behavior, even if the number of neutrons differs.

3. A lab report shows a potassium level of 4.5 millimoles per liter (mmol/L). Is this within the normal range of 3.5 to 5.3 mmol/L?

A. No, it is too low.
B. Yes, it is within the normal range.
C. No, it is too high.
D. Cannot be determined without additional information.

Correct answer: B

Rationale: The potassium level of 4.5 mmol/L falls within the normal range provided (3.5 to 5.3 mmol/L). 5. An infant's feeding schedule prescribes 120 milliliters of formula every 3 hours. How many ounces of formula should be prepared for a 24-hour period?

4. What is the function of ribosomes?

A. Packaging and transporting proteins
B. Storing genetic material
C. Controlling cell division
D. Synthesizing proteins

Correct answer: D

Rationale: The correct answer is D: 'Synthesizing proteins.' Ribosomes are the cellular organelles responsible for protein synthesis. They read the mRNA and assemble amino acids into proteins according to the genetic information encoded in the mRNA. This process is crucial for building and maintaining cellular structures, enzymes, and various other proteins essential for the functioning of the cell. Options A, B, and C do not accurately describe the primary function of ribosomes, making them incorrect choices for this question.

5. Which group of elements is known for their reactivity and ability to form strong bonds with other elements?

A. Noble gases
B. Halogens
C. Alkali metals
D. Transition metals

Correct answer: B

Rationale: Rationale: Halogens are a group of elements in the periodic table that are known for their high reactivity and ability to form strong bonds with other elements. They have seven valence electrons, which makes them highly reactive as they only need one more electron to achieve a stable electron configuration. Halogens readily form compounds with other elements by gaining an electron to achieve a full outer shell, resulting in the formation of strong covalent bonds. In contrast, noble gases (option A) are known for their inertness and stable electron configurations, alkali metals (option C) are highly reactive but not as strong bond formers as halogens, and transition metals (option D) are known for their variable oxidation states and ability to form complex ions but are not as reactive as halogens in terms of bond formation.

6. 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.