which of the following describes one responsibility of the integumentary system

ATI TEAS 7

ATI TEAS 7 Science Practice Test

1. Which of the following describes a responsibility of the integumentary system?

A. Distributing vital substances, such as nutrients, throughout the body.
B. Blocking pathogens that cause disease.
C. Sending leaked fluids from the cardiovascular system back to the blood vessels.
D. Storing bodily hormones that influence gender traits.

Correct answer: B

Rationale: The correct responsibility of the integumentary system is to act as a barrier that blocks pathogens from entering the body, thus helping to prevent diseases and infections. This function serves as the first line of defense for the body against external threats. Choices A, C, and D are incorrect. Choice A is a function of the circulatory system, not the integumentary system. Choice C relates to the lymphatic system, not the integumentary system. Choice D involves the endocrine system, not the integumentary system.

2. Which of the following cell organelles is the site of lipid synthesis?

A. smooth endoplasmic reticulum
B. ribosome
C. rough endoplasmic reticulum
D. Golgi apparatus

Correct answer: A

Rationale: The correct answer is the smooth endoplasmic reticulum. This organelle lacks ribosomes on its surface, unlike the rough endoplasmic reticulum, which is involved in protein synthesis. The enzymes present in the smooth endoplasmic reticulum are responsible for synthesizing lipids such as phospholipids and steroids. Choice B, ribosomes, are responsible for protein synthesis and not lipid synthesis. Choice C, rough endoplasmic reticulum, is involved in protein synthesis due to the presence of ribosomes. Choice D, Golgi apparatus, is responsible for modifying, sorting, and packaging proteins for secretion, not lipid synthesis.

3. The neutral theory of molecular evolution proposes that:

A. Most mutations in DNA are selectively neutral and do not affect an organism's fitness.
B. All mutations are beneficial and contribute to the adaptation of a population.
C. The rate of evolution is primarily driven by strong directional selection pressures.
D. Genetic drift plays a negligible role in shaping genetic variation within populations.

Correct answer: A

Rationale: Rationale: A) The neutral theory of molecular evolution, proposed by Motoo Kimura in the 1960s, suggests that the majority of mutations that occur in DNA are selectively neutral, meaning they do not have a significant impact on an organism's fitness. These neutral mutations are not subject to natural selection and are allowed to accumulate in populations over time. This theory helps explain the high levels of genetic variation observed within populations. B) Option B is incorrect because not all mutations are beneficial. Mutations can be neutral, harmful, or beneficial, and the neutral theory specifically focuses on the idea that many mutations are neutral in their effects. C) Option C is incorrect because the neutral theory suggests that evolution is not primarily driven by strong directional selection pressures. Instead, it emphasizes the role of genetic drift and the accumulation of neutral mutations in shaping genetic variation. D) Option D is incorrect because

4. Microfilaments and microtubules are both components of the cytoskeleton, but they have different functions. Which of these describes microfilaments?

A. Provide structural support and shape
B. Facilitate cell movement and contraction
C. Form the mitotic spindle during cell division
D. Transport materials within the cell

Correct answer: A

Rationale: Microfilaments are thin, solid rods made of the protein actin and are primarily responsible for providing structural support to the cell and determining its shape. While they also play a role in cell movement, their main function is related to maintaining the structural integrity of the cell. Choice B, 'Facilitate cell movement and contraction,' describes microtubules, which are responsible for facilitating cell movement, providing structural support, and aiding in cell division. Choice C, 'Form the mitotic spindle during cell division,' specifically refers to the function of microtubules in forming the mitotic spindle. Choice D, 'Transport materials within the cell,' is characteristic of microtubules that are involved in intracellular transport of organelles and materials within the cell.

5. In which regions of the digestive system is amylase produced?

A. pancreas and salivary glands
B. gall bladder and salivary glands
C. gall bladder and liver
D. pancreas and liver

Correct answer: A

Rationale: Amylase is an enzyme that breaks down carbohydrates into smaller sugars. It is produced in the pancreas and salivary glands. The salivary glands release amylase into the mouth during chewing, where it initiates the breakdown of carbohydrates. The pancreas also secretes amylase into the small intestine to further assist in carbohydrate digestion. Choices B, C, and D are incorrect as the gall bladder does not produce amylase, and the liver's primary function is not the production of amylase for carbohydrate breakdown.