how does the developing fetus primarily eliminate metabolic wastes

ATI TEAS 7

ATI TEAS Practice Science Test

1. How does the developing fetus primarily eliminate metabolic wastes?

A. The developing fetus does not produce metabolic wastes.
B. Fetal waste is excreted as feces, which pass into the mother's anus.
C. Fetal waste is passed down the umbilical cord to the mother's circulatory system.
D. Fetal waste is passed down the umbilical cord and leaves the mother's body via the vagina.

Correct answer: C

Rationale: Metabolic wastes produced by the developing fetus are eliminated primarily by being passed down the umbilical cord to the mother's circulatory system. Once in the mother's blood, these wastes are then filtered and excreted by the mother's kidneys. Choice A is incorrect because the developing fetus does produce metabolic wastes. Choice B is incorrect as fetal waste does not pass into the mother's anus. Choice D is incorrect as fetal waste does not leave the mother's body via the vagina.

2. What is the sensory threshold?

A. The smallest amount of stimulus required for an individual to feel a sensation
B. The amount of stimulus required for an individual to feel pain
C. The amount of stimulus required to cause an individual to move away from the stimulus
D. The place from which the stimulus is coming

Correct answer: A

Rationale: The sensory threshold refers to the smallest amount of stimulus required for an individual to perceive or feel a sensation. It is the minimum level of stimulus intensity that is detectable by an individual. Choice B is incorrect because the sensory threshold is not specifically related to feeling pain but rather to perceiving any sensation. Choice C is incorrect as the sensory threshold is about perception and not necessarily physical reaction. Choice D is incorrect as it describes the source of the stimulus, not the threshold for perception.

3. Which of the following is a component of the immune system?

A. Red blood cells
B. White blood cells
C. Platelets
D. Plasma

Correct answer: B

Rationale: White blood cells are a crucial component of the immune system as they play a key role in fighting infections and foreign invaders. Red blood cells are primarily involved in oxygen transport, platelets are important for blood clotting, and plasma is the liquid component of blood that carries various substances but is not directly involved in the immune response.

4. What is the function of the pharynx?

A. Allow food and air to pass into the body
B. Warm and moisten air during inhalation
C. Create a chest cavity at the base of the lungs
D. Provide structural support to the alveolar region

Correct answer: A

Rationale: The correct answer is A: 'Allow food and air to pass into the body.' The pharynx serves as a common pathway for both food and air. It connects the nasal cavity and mouth to the larynx and esophagus, enabling the passage of both food and air into their respective pathways. Choices B, C, and D are incorrect as they do not accurately describe the function of the pharynx. Option B is incorrect because the warming and moistening of air primarily occur in the nasal cavity and not in the pharynx. Option C is incorrect as the creation of a chest cavity is mainly related to the thoracic cavity, not the pharynx. Option D is also incorrect as the structural support to the alveolar region is provided by other structures like the alveoli and surrounding tissues, not the pharynx.

5. Which part of the brain is responsible for controlling involuntary actions like breathing and heart rate?

A. Cerebellum
B. Medulla oblongata
C. Cerebrum
D. Thalamus

Correct answer: B

Rationale: The correct answer is the Medulla oblongata. This region of the brain is located in the brainstem and is responsible for controlling vital autonomic functions such as breathing, heart rate, and blood pressure. The Cerebellum (Choice A) is primarily involved in coordination and balance. The Cerebrum (Choice C) is responsible for higher brain functions like thinking and voluntary muscle movement. The Thalamus (Choice D) acts as a relay station for sensory information but is not primarily responsible for controlling involuntary actions like breathing and heart rate.