melanin the pigment responsible for skin color is produced by
Logo

Nursing Elites

ATI TEAS 7

TEAS 7 practice test free science

1. Melanin, the pigment responsible for skin color, is produced by

Correct answer: B

Rationale: Melanocytes are the cells responsible for producing melanin, the pigment that determines skin color. Melanin gives skin its color and protects it from the harmful effects of UV radiation. Keratinocytes produce keratin, a tough protein that forms the outer layer of the skin, hair, and nails. Sebocytes produce sebum, an oily substance that helps moisturize and protect the skin. Langerhans cells are a type of immune cell found in the skin that play a role in protecting against infections and foreign substances but do not produce melanin.

2. How many electrons are typically found in each shell of a neutral aluminum atom with 13 electrons in its electron cloud?

Correct answer: C

Rationale: In a neutral aluminum atom with 13 electrons, the electron distribution typically follows the electron shell filling order based on the Aufbau principle. The first shell can hold a maximum of 2 electrons, the second shell can hold up to 8 electrons, and the third shell can hold up to 8 electrons as well. Therefore, the distribution would be 2 electrons in the first shell, 8 electrons in the second shell, and 3 electrons in the third shell, totaling 13 electrons. Choice A is incorrect as it exceeds the maximum number of electrons the shells can hold. Choice B is incorrect as it does not distribute the electrons correctly among the shells. Choice D is incorrect as it also does not distribute the electrons correctly among the shells.

3. What is the definition of work in physics?

Correct answer: C

Rationale: In physics, work is defined as the transfer of energy through motion along a direction. When a force is applied to an object, and the object moves in the direction of the force, work is done on the object. The work done is calculated as the force applied multiplied by the distance the object moves in the direction of the force. Choices A and B do not fully capture the essence of work, as work is about energy transfer through motion, not merely applying force to objects at rest or in motion. Choice D is incorrect as work is not a measure of an object's potential energy; rather, it is the transfer of energy through motion.

4. Define the term 'velocity' in relation to motion.

Correct answer: A

Rationale: Velocity is a vector quantity that describes the speed of an object along with its direction of motion. Unlike speed, which is a scalar quantity focusing solely on the magnitude of motion, velocity considers both speed and direction. Therefore, the best definition of velocity is 'speed in a specific direction.' Choice B, 'Distance traveled in a given time,' is incorrect as it defines speed rather than velocity. Choice C, 'Rate of change of position,' is more aligned with the definition of velocity but lacks the specificity of direction. Choice D, 'Acceleration due to gravity,' is unrelated to the definition of velocity and refers to a different concept in physics.

5. What is the term for the shedding of the outermost layer of the epidermis?

Correct answer: A

Rationale: Desquamation is the correct term for the shedding of the outermost layer of the epidermis. This process is essential for skin renewal, allowing the removal of dead skin cells from the skin's surface. Exfoliation, on the other hand, involves the removal of dead skin cells through mechanical or chemical methods. Keratinization refers to the process where skin cells produce the protein keratin, contributing to the skin's protective barrier. Epidermolysis is a condition characterized by the separation of the epidermis from the dermis due to a structural defect in the skin.

Similar Questions

What potential consequences can chromosomal nondisjunction have on offspring?
What is the function of the Golgi apparatus?
Which of the following is a strong base commonly used in cleaning products?
Which of the following structures is responsible for preventing the backflow of blood from the left ventricle into the left atrium?
What is the term for a substance that can act as both a proton donor and a proton acceptor?

Access More Features

ATI TEAS Premium Plus
$149.99/ 90 days

  • Actual ATI TEAS 7 Questions
  • 3,000 questions with answers
  • 90 days access

ATI TEAS Basic
$99/ 30 days

  • 3,000 Questions with answers
  • 30 days access

Other Courses