1. Which structure contains the genetic material (DNA) of the cell?

A. Cytoplasm
B. Nucleus
C. Cell wall (only present in plant cells)
D. Golgi apparatus

Correct answer: B

Rationale: The correct answer is B: Nucleus. The nucleus is the organelle that contains the genetic material (DNA) of the cell. It acts as the control center of the cell, regulating gene expression and coordinating cellular activities. The cytoplasm, option A, is the jelly-like substance that fills the cell and surrounds the organelles, but it does not contain the genetic material. The cell wall, option C, is a rigid structure found in plant cells that provides support and protection, but it does not house the DNA. The Golgi apparatus, option D, is responsible for modifying, sorting, and packaging proteins for secretion, but it does not store the genetic material of the cell. Therefore, the nucleus is the structure that contains the genetic material in a cell.

2. The van't Hoff factor (i) accounts for the number of particles a solute dissociates into in solution. For a compound that dissociates completely in water, i would be...

A. 0
B. Less than 1
C. 1
D. More than 1

Correct answer: C

Rationale: The van't Hoff factor (i) is used to account for the number of particles a solute dissociates into in solution. For a compound that dissociates completely in water, such as a strong electrolyte, i would be equal to the total number of ions produced by the dissociation. Since the compound dissociates completely, it forms an equal number of ions, resulting in an i value of 1. Therefore, the correct answer is C: 1.

3. What is the process of cells becoming specialized to perform specific functions called?

A. Cell division
B. Cell differentiation
C. Cell growth
D. Cell regeneration

Correct answer: B

Rationale: Rationale: A) Cell division refers to the process by which a parent cell divides into two or more daughter cells. B) Cell differentiation is the process by which cells become specialized to perform specific functions. During differentiation, cells acquire specific structures and functions that allow them to carry out particular roles in the body. C) Cell growth is the process by which cells increase in size and number. D) Cell regeneration is the process by which new cells are produced to replace damaged or lost cells in an organism. In this context, the process of cells becoming specialized to perform specific functions is best described as cell differentiation.

4. The major site for nutrient absorption in the digestive system is the:

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

Correct answer: C

Rationale: The correct answer is C: Small intestine. The small intestine is the major site for nutrient absorption in the digestive system. It is where most of the digestion and absorption of nutrients from food takes place. The small intestine has villi and microvilli that increase its surface area, allowing for efficient absorption of nutrients like sugars, amino acids, and fatty acids into the bloodstream. The mouth is primarily responsible for mechanical digestion through chewing, while the stomach's main function is to break down food with enzymes and acids. The large intestine mainly absorbs water and electrolytes, with minimal nutrient absorption.

5. Histamine, released during an allergic reaction, causes symptoms like:

A. Fever and fatigue
B. Runny nose and itchiness
C. Muscle aches and joint pain
D. Cough and shortness of breath

Correct answer: B

Rationale: The correct answer is B: 'Runny nose and itchiness.' Histamine is a chemical released by the body during an allergic reaction. It causes various symptoms such as itching, sneezing, runny nose, and watery eyes. These symptoms are commonly associated with allergic reactions like hay fever or hives. Fever and fatigue (option A) are not directly caused by histamine release. Muscle aches and joint pain (option C) are not typical symptoms of histamine release during an allergic reaction. Cough and shortness of breath (option D) are more commonly associated with asthma or respiratory allergies rather than histamine release.

6. How can you differentiate between a bacterial and viral infection based solely on symptoms?

A. It's impossible to differentiate solely on symptoms.
B. Bacterial infections typically respond well to antibiotics, while viral infections don't.
C. Bacterial infections usually cause fever, while viral infections don't.
D. Viral infections often present with respiratory symptoms like a cough, while bacterial infections don't.

Correct answer: B

Rationale: Option B is the correct answer because bacterial infections are typically treated with antibiotics, while viral infections do not respond to antibiotics. This is a key differentiating factor between the two types of infections. While some symptoms may overlap between bacterial and viral infections, the response to antibiotic treatment is a reliable indicator. It's important to note that solely relying on symptoms to differentiate between bacterial and viral infections can be challenging since many symptoms can be similar. Therefore, the response to antibiotics is a more definitive way to distinguish between the two types of infections.