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. Which of the following is responsible for maintaining homeostasis in the body?

A. Brainstem
B. Hypothalamus
C. Medulla oblongata
D. Cerebrum

Correct answer: B

Rationale: The correct answer is the Hypothalamus (choice B). The hypothalamus plays a crucial role in maintaining homeostasis by regulating various bodily functions such as hunger, thirst, body temperature, and sleep cycles. While the brainstem (choice A) is involved in basic life functions like breathing and heart rate, it is not primarily responsible for maintaining homeostasis. The medulla oblongata (choice C) is part of the brainstem and controls vital autonomic functions like breathing and heart rate, but it is not the main regulator of homeostasis. The cerebrum (choice D) is responsible for higher brain functions such as thinking, memory, and voluntary movement, but it is not directly involved in maintaining overall bodily balance or homeostasis.

3. Which of the following are functions of the liver?

A. Supports waste disposal
B. Aids in blood clotting through plasma protein synthesis
C. Emulsifies fats through bile production
D. All of the above

Correct answer: D

Rationale: The liver performs various essential functions in the body. It supports waste disposal by breaking down toxins and producing bile to eliminate waste, aids in blood clotting through the synthesis of plasma proteins like fibrinogen, and emulsifies fats by producing bile that helps in fat digestion. All the statements accurately describe functions of the liver, making option D 'All of the above' the correct choice. Option A is incorrect as it oversimplifies the waste disposal function without mentioning the breakdown of toxins. Option B is incorrect as it only focuses on blood clotting and not the other functions of the liver. Option C is incorrect as it solely emphasizes fat emulsification and does not cover the liver's other crucial roles.

4. Which of the following is NOT a recognized mode of natural selection?

A. Directional selection (favoring one extreme trait value on a spectrum)
B. Disruptive selection (favoring both extreme trait values on a spectrum)
C. Stabilizing selection (favoring the average trait value on a spectrum)
D. Sexual selection (selection based on mate choice that influences reproductive success)

Correct answer: D

Rationale: A) Directional selection is a recognized mode of natural selection where one extreme trait value on a spectrum is favored over others, leading to a shift in the average trait value over time. B) Disruptive selection is a recognized mode of natural selection where both extreme trait values on a spectrum are favored over the average trait value, potentially causing the population to split into distinct groups. C) Stabilizing selection is a recognized mode of natural selection favoring the average trait value on a spectrum over extreme values, resulting in reduced genetic diversity. D) Sexual selection differs from traditional natural selection modes as it involves mate choice and competition for mates, not direct selection pressure on traits affecting survival and reproduction in the environment. Sexual selection can drive the evolution of traits enhancing an individual's attractiveness for mating purposes.

5. What is the primary function of ribosomes in a cell?

A. Protein synthesis
B. DNA replication
C. Cell division
D. Lipid synthesis

Correct answer: A

Rationale: The correct answer is A: Protein synthesis. Ribosomes are the cellular organelles responsible for protein synthesis. They read the messenger RNA (mRNA) and translate the genetic information into specific proteins. This process is essential for building and maintaining the structures and functions of the cell. Choice B, DNA replication, is incorrect because ribosomes are not involved in replicating DNA; that process occurs in the nucleus. Choice C, cell division, is incorrect as ribosomes are not directly involved in cell division but rather in protein synthesis. Choice D, lipid synthesis, is also incorrect as ribosomes are not responsible for synthesizing lipids, which primarily occurs in the endoplasmic reticulum and other organelles.