Quizlet HESI A2 Anatomy and Physiology

Correct Answer: B

Rationale: The correct answer is B: Absorbing nutrients. The small intestine is where the majority of nutrient absorption occurs in the digestive system. Its long and highly folded structure provides a large surface area for nutrients to be absorbed into the bloodstream. This process is essential for the body to obtain the necessary vitamins, minerals, proteins, and other nutrients from food. Breaking down fats (choice A) primarily occurs in the small intestine but is not its primary function. Secreting digestive enzymes (choice C) is the role of the pancreas and liver, while storing bile (choice D) is the function of the gallbladder.

Correct Answer: B

Rationale: The correct answer is B: To protect internal organs and provide support. The skeletal system consists of bones that serve as the framework of the body, supporting and protecting internal organs. Bones also provide structure for muscles to attach to, enabling movement. Choices A, C, and D are incorrect because the skeletal system does not produce red blood cells (that's the function of the bone marrow), regulate body temperature (that's the role of the skin and hypothalamus), or store calcium (bones do store calcium, but it's not the main function of the skeletal system).

Correct Answer: B

Rationale: The correct answer is B: Small intestine. The small intestine is responsible for absorbing nutrients from the food we eat. It has specialized structures called villi that increase the surface area for absorption. The stomach (A) primarily helps in digestion, the large intestine (C) absorbs water and salts, and the esophagus (D) is a tube that carries food from the mouth to the stomach. Therefore, the small intestine is the correct choice for absorbing nutrients in the digestive system.

Correct Answer: B

Rationale: The primary function of the circulatory system is to transport oxygen and nutrients throughout the body. The heart pumps blood containing oxygen and nutrients to all cells and tissues. This process supports cellular functions and provides energy. Hormone production (A) is mainly regulated by the endocrine system. Fighting infections (C) is primarily the role of the immune system. Regulating body temperature (D) is primarily controlled by the thermoregulatory system. Overall, the circulatory system's main role is the transport of oxygen and nutrients, making choice B the correct answer.

Correct Answer: B

Rationale: The correct answer is B: To exchange gases. Alveoli are tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide takes place. Oxygen from the air we breathe enters the blood through the alveoli, and carbon dioxide is removed from the blood and exhaled. This process is essential for respiration. Explanation of other choices: A: To filter blood - This is incorrect because the alveoli do not filter blood. Filtering of blood primarily occurs in the kidneys and liver. C: To transport nutrients - This is incorrect because the alveoli are not involved in transporting nutrients. Nutrient transport mainly occurs through the bloodstream. D: To store oxygen - This is incorrect because the alveoli do not store oxygen. Oxygen is temporarily stored in the red blood cells and muscle tissues.