what does monophyletic mean in the context of classification

ATI TEAS 7

Mometrix TEAS 7 science practice test

1. What does 'monophyletic' mean in the context of classification?

A. A group with a single representative organism
B. A group with diverse and unrelated members
C. A group with similar functions but different origins
D. A group descended from a common ancestor

Correct answer: D

Rationale: In the context of classification, 'monophyletic' refers to a group that includes a common ancestor and all of its descendants. This group shares a single evolutionary origin and forms a complete branch on a phylogenetic tree. Monophyletic groups are considered natural and valid taxonomic units because they reflect evolutionary relationships accurately. Option D is the correct choice as it accurately defines the term 'monophyletic' in the context of classification. Choices A, B, and C are incorrect. Choice A is incorrect because 'monophyletic' does not refer to a group with a single representative organism but rather a group descended from a common ancestor. Choice B is incorrect as a monophyletic group consists of related, not diverse and unrelated, members. Choice C is incorrect as a monophyletic group includes descendants from a common ancestor, not just organisms with similar functions but different origins.

2. What is the main function of the lungs?

A. To transport oxygen and nutrients throughout the body
B. To coordinate movement and sensory information
C. To filter waste products from the blood
D. To exchange oxygen and carbon dioxide between the body and the environment

Correct answer: D

Rationale: The main function of the lungs is to exchange oxygen and carbon dioxide between the body and the environment. This process occurs through the alveoli in the lungs where oxygen from inhaled air enters the bloodstream, and carbon dioxide is removed from the bloodstream and exhaled. Option A is incorrect as the transportation of oxygen and nutrients throughout the body is primarily carried out by the circulatory system, not the lungs. Option B is incorrect as coordinating movement and sensory information is a function of the nervous system, not the lungs. Option C is incorrect as filtering waste products from the blood is primarily the role of the kidneys, not the lungs. Therefore, the correct answer is D.

3. Which group of elements is known for their vibrant colors and is commonly used in fireworks?

A. Noble gases
B. Alkali metals
C. Halogens
D. Transition metals

Correct answer: D

Rationale: The correct answer is D: Transition metals. Transition metals are known for their vibrant colors and are commonly used in fireworks due to their ability to emit specific colors of light. The diverse electronic configurations of transition metals allow them to produce a variety of hues, making them ideal for creating colorful displays in fireworks. Choice A, Noble gases, do not typically produce vibrant colors in fireworks as they are colorless and odorless gases. Choice B, Alkali metals, are not known for their colorful displays in fireworks. Choice C, Halogens, can produce colors in fireworks, but they are not as commonly used for their vibrant hues compared to transition metals.

4. What is meant by the term 'goiter'?

A. Overproduction of cortisol from the adrenal glands
B. Excessive growth of the thyroid gland
C. Underproduction of parathyroid hormone (PTH)
D. Deficiency of growth hormone from the pituitary gland

Correct answer: B

Rationale: A goiter is a condition characterized by the abnormal enlargement of the thyroid gland. This enlargement can be caused by various factors such as iodine deficiency, thyroid nodules, inflammation, or other thyroid disorders. It is not associated with the overproduction of cortisol (Choice A), underproduction of parathyroid hormone (Choice C), or deficiency of growth hormone (Choice D). Therefore, the correct answer is B, excessive growth of the thyroid gland.

5. Which of the following is NOT a typical component of healthy semen?

A. Sperm
B. Fructose (sugar)
C. Prostaglandins
D. Urine

Correct answer: D

Rationale: Healthy semen is composed of sperm, fructose (sugar), and prostaglandins. Urine is not a typical component of semen. While semen is ejaculated during sexual activity, urine is expelled through a separate pathway in the male reproductive system. Therefore, the correct answer is 'Urine.' Choices A, B, and C are all components found in healthy semen.