1. Which structure in the respiratory system serves as a passageway for both air and food, with a flap-like structure that prevents food from entering the trachea during swallowing?

A. Larynx
B. Pharynx
C. Trachea
D. Bronchi

Correct answer: B

Rationale: The correct answer is B: Pharynx. The pharynx is a structure in the respiratory system that serves as a passageway for both air and food. It has a flap-like structure called the epiglottis, which prevents food from entering the trachea during swallowing. The larynx is commonly known as the voice box and is responsible for sound production. The trachea is a tube that carries air to and from the lungs, and the bronchi are the two main branches that lead from the trachea to the lungs. Therefore, the pharynx is the correct answer as it specifically fits the description provided in the question.

2. What phenomenon occurs when light passes through a medium but does not change direction, such as when passing through a window?

A. Diffraction
B. Reflection
C. Dispersion
D. Transmission

Correct answer: d

Rationale: Transmission occurs when light passes through a medium without changing direction, as observed when light passes through a window.

3. Which of the following is an example of aseptic technique?

A. Washing hands with soap and water before surgery
B. Coughing into your elbow
C. Sharing a stethoscope without cleaning
D. Leaving a wound dressing exposed

Correct answer: A

Rationale: Rationale: Aseptic technique refers to practices that help prevent the introduction of harmful microorganisms into a sterile environment. Washing hands with soap and water before surgery is an essential component of aseptic technique as it helps reduce the number of microorganisms on the hands, decreasing the risk of introducing pathogens into the surgical site. Coughing into your elbow is a good hygiene practice to prevent the spread of respiratory infections but is not specifically related to aseptic technique. Sharing a stethoscope without cleaning can introduce microorganisms from one patient to another, compromising aseptic conditions. Leaving a wound dressing exposed can lead to contamination and infection, which is contrary to aseptic technique.

4. Which force opposes the relative motion between surfaces in contact?

A. Tension force
B. Frictional force
C. Gravitational force
D. Magnetic force

Correct answer: b

Rationale: Friction is the force that opposes motion between surfaces in contact.

5. What type of bond forms between elements when they share electrons?

A. Covalent bond
B. Ionic bond
C. Metallic bond
D. Hydrogen bond

Correct answer: A

Rationale: In a covalent bond, atoms share electrons, creating a strong attraction that holds them together

6. Bile, a yellowish-green fluid, is stored in the gallbladder and released into the small intestine during digestion. What is the primary function of bile in digestion?

A. Break down carbohydrates
B. Break down proteins
C. Emulsify fats
D. Neutralize stomach acid

Correct answer: C

Rationale: The primary function of bile in digestion is to emulsify fats. Bile contains bile salts that help break down large fat globules into smaller droplets, which increases the surface area for enzymes to work on and aids in the absorption of fats in the small intestine. This process is essential for the digestion and absorption of dietary fats. Bile does not directly break down carbohydrates or proteins, and it is not involved in neutralizing stomach acid, making option C the correct answer.