1. The fluid-filled, jelly-like substance within the cell that suspends the organelles is called the:

A. Nucleus
B. Cytoplasm
C. Plasma membrane
D. Golgi apparatus

Correct answer: B

Rationale: The correct answer is B: Cytoplasm. Cytoplasm is the fluid-filled, jelly-like substance within the cell that suspends the organelles. It is where many cellular processes take place, such as metabolism and protein synthesis. The nucleus (option A) is the organelle that contains the cell's genetic material, the plasma membrane (option C) is the outer boundary of the cell that regulates what enters and exits the cell, and the Golgi apparatus (option D) is involved in processing and packaging proteins. Understanding the functions of each organelle is crucial in recognizing that the cytoplasm is the correct answer in this context.

2. A bottle of hand sanitizer contains 70% alcohol. If 5ml of sanitizer are used, how much pure alcohol is present?

A. 1.4ml
B. 2.1ml
C. 2.8ml
D. 3.5ml

Correct answer: D

Rationale: Multiply the total sanitizer volume (5ml) by the alcohol percentage (70%) to get 3.5ml of pure alcohol.

3. Homologous structures are those that:

A. Have the same function but different origins
B. Have different functions but the same origin
C. Are similar in appearance and function due to shared ancestry
D. Are identical in both appearance and function

Correct answer: C

Rationale: Rationale: - Option A is incorrect because structures with the same function but different origins are analogous structures, not homologous structures. - Option B is incorrect because structures with different functions but the same origin are also not homologous structures; they are considered to be vestigial structures. - Option D is incorrect because structures that are identical in both appearance and function are not necessarily homologous; they could be the result of convergent evolution. Homologous structures are those that share similarities in appearance and function due to being inherited from a common ancestor. These structures may have undergone modifications over time to adapt to different functions in different species, but their fundamental similarities can be traced back to a shared evolutionary history.

4. Which vitamin is essential for calcium absorption and bone health?

A. Vitamin A
B. Vitamin C
C. Vitamin D
D. Vitamin E

Correct answer: C

Rationale: The correct answer is Vitamin D. Vitamin D plays a crucial role in calcium absorption in the intestines, which is essential for maintaining strong and healthy bones. It helps regulate calcium and phosphorus levels in the body, promoting bone mineralization and growth. Vitamin A is important for vision and immune function, not specifically for bone health. Vitamin C is essential for collagen synthesis but not directly involved in calcium absorption. Vitamin E is an antioxidant that protects cells from damage but does not have a direct role in bone health. Therefore, Vitamin D is the correct choice for supporting calcium absorption and bone health.

5. What is the role of RNA in protein synthesis?

A. Stores genetic information
B. Decodes genetic information
C. Provides energy for the process
D. Transports amino acids to the ribosomes

Correct answer: B

Rationale: Rationale: RNA plays a crucial role in protein synthesis by decoding the genetic information stored in DNA and carrying it to the ribosomes where proteins are synthesized. This process involves transcription, where RNA is synthesized from DNA, and translation, where the information in RNA is used to assemble amino acids into proteins. RNA acts as a messenger between DNA and the ribosomes, ensuring that the correct sequence of amino acids is used to build proteins according to the genetic code. Therefore, option B is the most appropriate choice as it accurately describes the role of RNA in protein synthesis.

6. Which type of isomerism arises due to differences in the arrangement of atoms around a double bond?

A. Chain isomerism
B. Functional group isomerism
C. Cis-trans isomerism
D. Stereoisomerism

Correct answer: C

Rationale: The correct answer is C: Cis-trans isomerism. Cis-trans isomerism, also known as geometric isomerism, arises due to differences in the spatial arrangement of atoms around a double bond. In cis isomers, similar groups are on the same side of the double bond, while in trans isomers, similar groups are on opposite sides. This type of isomerism is specific to compounds with restricted rotation around a double bond, leading to distinct spatial arrangements and different properties. Chain isomerism (A) refers to isomers with different carbon chain arrangements, functional group isomerism (B) involves different functional groups, and stereoisomerism (D) encompasses all isomers that have the same connectivity but differ in spatial arrangement.