1. Which of the following is NOT a type of epithelium

A. Stratified squamous
B. Simple cuboidal
C. Stratified columnar
D. Stratified columnar

Correct answer: D

Rationale: The correct answer is D, 'Stratified columnar.' Epithelial tissues are classified based on their structure and function. Stratified squamous epithelium consists of multiple layers of flattened cells and is found in areas that need protection, like the skin. Simple cuboidal epithelium is a single layer of cube-shaped cells that function in secretion and absorption, commonly found in kidney tubules. Stratified columnar epithelium is a rare type with multiple layers of column-shaped cells, primarily found in the male urethra. Since 'Stratified columnar' is a valid type of epithelium, it is NOT the correct answer for this question.

2. What is the waxy or oily substance produced by sebaceous glands that helps lubricate the skin and hair?

A. Keratin
B. Melanin
C. Sebum
D. Sweat

Correct answer: C

Rationale: The correct answer is C: Sebum. Sebum is a waxy or oily substance produced by the sebaceous glands in the skin. It helps lubricate and waterproof the skin and hair, preventing them from drying out. Keratin is a protein found in the skin, hair, and nails, providing structure and strength. Melanin is a pigment that gives color to the skin, hair, and eyes. Sweat is produced by sweat glands and helps regulate body temperature by cooling the skin through evaporation. In this question, sebum specifically refers to the substance produced by sebaceous glands, making it the correct answer.

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. What is the primary function of hair on the human body?

A. Insulation
B. Sensory perception
C. Protection
D. Vitamin D synthesis

Correct answer: A

Rationale: The primary function of hair on the human body is insulation. Hair acts as a protective layer to help regulate body temperature by trapping heat close to the skin. This insulation property is especially important in colder climates to prevent excessive heat loss from the body. While hair can also provide some level of protection from external elements and minor injuries, its main role is to insulate the body. Sensory perception is mainly attributed to nerve endings in the skin rather than hair. Vitamin D synthesis is primarily dependent on exposure to sunlight rather than hair. Therefore, option A, insulation, is the correct answer.

5. What happens to the frequency of a wave when its wavelength is doubled, assuming the speed remains constant?

A. Frequency remains the same.
B. Frequency is halved.
C. Frequency is doubled.
D. Frequency information is insufficient to determine.

Correct answer: C

Rationale: Since the wave speed is constant, if the wavelength increases, the frequency must decrease to maintain the same energy transfer per unit time.