ATI TEAS 7 Science

Correct Answer: B

Rationale: The correct answer is B: Bacteria. Dysentery is primarily caused by pathogenic bacteria such as Shigella or Escherichia coli. Bacteria are single-celled microorganisms that can infect the intestines and cause symptoms like bloody diarrhea and abdominal pain. Helminths are parasitic worms that typically cause different types of infections. Protozoa are single-celled organisms that can also cause intestinal infections, but they are not the primary cause of dysentery. Fungi do not typically cause dysentery; they are more commonly associated with skin infections or respiratory issues. In summary, the correct answer is B because dysentery is most commonly caused by bacterial infections in the intestines.

Correct Answer: B

Rationale: The correct answer is B: Cardiac muscle. Cardiac muscle is found exclusively in the heart, allowing it to contract rhythmically and involuntarily to pump blood throughout the body. Smooth muscle (A) is found in organs like the intestines and blood vessels, not in the heart. Skeletal muscle (C) is attached to bones and responsible for voluntary movements, while voluntary muscle (D) is a general term that refers to skeletal muscle controlled voluntarily. Therefore, the unique characteristics of cardiac muscle make it the correct answer for this question.

Correct Answer: B

Rationale: The correct answer is B: Skeletal. Skeletal muscles are responsible for voluntary movements because they are attached to bones and are under conscious control. They enable us to move our body parts intentionally. Smooth muscles (A) are involuntary and found in internal organs. Cardiac muscles (C) are also involuntary and specific to the heart. Option D simply defines a term and is not a type of muscle.

Correct Answer: C

Rationale: The correct answer is C: Emulsify fats. Bile helps emulsify fats by breaking them down into smaller droplets, increasing the surface area for enzymes to digest fats. This aids in the absorption of fats and fat-soluble vitamins in the small intestine. Choice A is incorrect because bile does not break down carbohydrates. Choice B is incorrect as bile does not break down proteins. Choice D is incorrect because bile does not neutralize stomach acid; rather, it helps with fat digestion in the small intestine.

Correct Answer: A

Rationale: The correct answer is A: Calcitonin. Calcitonin is produced by the thyroid gland and functions to lower blood calcium levels by promoting calcium deposition in bones and inhibiting calcium reabsorption in the kidneys. This hormone opposes the action of parathyroid hormone (PTH), which increases blood calcium levels by promoting calcium release from bones and increasing calcium reabsorption in the kidneys. Thyroxine is a thyroid hormone that regulates metabolism and growth, not calcium levels. Insulin is a hormone produced by the pancreas that regulates blood sugar levels, not calcium levels. Thus, A is the correct answer as it directly regulates calcium levels in the blood through its actions on bones and kidneys.