Practice TEAS Science Test

Correct Answer: B

Rationale: The correct answer is B: Gallbladder. The gallbladder stores and concentrates bile produced by the liver, releasing it into the small intestine to aid in digestion. The liver produces bile but does not store it. The pancreas produces digestive enzymes, not bile. The stomach produces gastric juices for digestion, not bile.

Correct Answer: B

Rationale: The correct answer is B: Alveoli. Alveoli are tiny air sacs in the lungs where gas exchange occurs. Oxygen from the air we breathe passes into the blood vessels surrounding the alveoli, while carbon dioxide from the blood moves into the alveoli to be exhaled. The other choices are incorrect because: A: Trachea is the windpipe that carries air to and from the lungs, but gas exchange does not occur there. C: Bronchioles are small air passages that branch off the bronchi, leading air to the alveoli, but they are not the site of gas exchange. D: Diaphragm is a muscle that helps with breathing by expanding and contracting the chest cavity, but it is not directly involved in gas exchange.

Correct Answer: B

Rationale: The correct answer is B: Jejunum. The jejunum is the primary site of absorption in the small intestine due to its extensive surface area, presence of villi and microvilli that increase absorption capacity, and higher blood supply compared to other regions. It is where most nutrients such as carbohydrates, proteins, and fats are absorbed. The duodenum (A) is mainly responsible for initial digestion, the ileum (C) absorbs bile salts, vitamin B12, and some nutrients, and the cecum (D) is part of the large intestine and is not involved in nutrient absorption.

Correct Answer: B

Rationale: Iron is the correct answer because it is an essential component of hemoglobin, the protein in red blood cells responsible for transporting oxygen throughout the body. Without iron, the body cannot produce enough hemoglobin, leading to anemia. Calcium, potassium, and sodium do not play a direct role in hemoglobin synthesis. Calcium is important for bone health, potassium is crucial for nerve and muscle function, and sodium helps regulate fluid balance. Iron is the only element among the choices that is directly involved in hemoglobin formation.

Correct Answer: B

Rationale: The correct answer is B: Hip. A ball-and-socket joint allows for a wide range of motion in multiple directions. The hip joint fits this description, with the rounded head of the femur fitting into the socket of the pelvis. This joint enables movements like flexion, extension, abduction, adduction, and rotation. The other choices, such as the knee (A), elbow (C), and wrist (D), are not ball-and-socket joints. The knee is a hinge joint, the elbow is a hinge joint as well, and the wrist is a condyloid joint.