1. The muscular tube connecting the mouth to the stomach is lined with a mucous membrane. What is the main function of this mucous membrane?

A. Secretion of digestive enzymes
B. Absorption of nutrients
C. Lubrication and protection
D. Storage of bile

Correct answer: C

Rationale: The correct answer is C: Lubrication and protection. The mucous membrane lining the esophagus serves to provide lubrication for food as it travels from the mouth to the stomach, making it easier to swallow. Additionally, the mucous membrane protects the esophageal tissue from damage caused by the passage of food and liquids. This function is crucial in preventing irritation and inflammation of the esophagus, ensuring smooth and efficient digestion process. The mucous membrane does not secrete digestive enzymes (A), absorb nutrients (B), or store bile (D), as those functions are carried out by other digestive organs.

2. Which property of a wave remains constant when it crosses a boundary between two different media?

A. Frequency
B. Wavelength
C. Amplitude
D. Speed

Correct answer: d

Rationale: The speed of a wave remains constant when it crosses a boundary between two different media, although its direction may change.

3. Which element shares the same group (family) on the periodic table with helium (He)?

A. Neon (Ne)
B. Boron (B)
C. Carbon (C)
D. Oxygen (O)

Correct answer: A

Rationale: Neon (Ne). Both He and Ne belong to Group 18 (Noble Gases) due to their complete and stable outer electron shells.

4. What is the medical term for a urinary tract infection (UTI)?

A. Nephritis
B. Cystitis
C. Urethritis
D. All of the above

Correct answer: D

Rationale: The correct answer is D, 'All of the above.' A urinary tract infection (UTI) can affect different parts of the urinary system. Nephritis refers to inflammation of the kidneys, cystitis refers to inflammation of the bladder, and urethritis refers to inflammation of the urethra. Therefore, all of these terms can be used to describe a UTI depending on which part of the urinary tract is affected. It's important to differentiate between these terms to accurately diagnose and treat UTIs.

5. The largest bone in the human body is the:

A. Femur (thigh bone)
B. Tibia (shin bone)
C. Humerus (upper arm bone)
D. Scapula (shoulder blade)

Correct answer: A

Rationale: The correct answer is A: Femur (thigh bone). The femur is the longest and strongest bone in the human body, located in the thigh region. It plays a crucial role in supporting the body's weight and facilitating movement. The tibia (B) is commonly known as the shin bone and is located below the femur. The humerus (C) is the upper arm bone, and the scapula (D) is the shoulder blade. However, neither of these bones is the largest in the human body. Understanding the anatomy of the skeletal system is essential for identifying the largest bone in the body, which is the femur.

6. Bradycardia refers to a heart rate that is:

A. Normal (60-100 bpm)
B. Slightly elevated (100-120 bpm)
C. Significantly elevated (>120 bpm)
D. Abnormally slow (<60 bpm)

Correct answer: D

Rationale: The correct answer is D. Bradycardia refers to an abnormally slow heart rate, typically defined as being less than 60 beats per minute (bpm). A heart rate of 60-100 bpm is considered normal, not bradycardia. Choices B and C incorrectly describe elevated heart rates, which are not characteristic of bradycardia. Therefore, option D is the most accurate description of bradycardia as it signifies a heart rate that is slower than normal.