Practice TEAS Science Test

Correct Answer: D

Rationale: The correct answer is D: Glucose. Glucose is a monosaccharide, not a biological macromolecule. Biological macromolecules are large molecules made up of smaller subunits. Glycoproteins are proteins with attached carbohydrates, DNA is a nucleic acid, and phospholipids are lipids. Glucose, being a simple sugar, is not considered a macromolecule.

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: Laryngopharynx. The laryngopharynx is part of the pharynx where both the respiratory and digestive systems intersect. It serves as a common passageway for both food and air. When we swallow, the epiglottis covers the larynx to prevent food from entering the trachea. A: The esophagus is solely a passageway for food from the mouth to the stomach. C: The nasopharynx is a part of the upper respiratory tract and not involved in the passage of food. D: The trachea is strictly a passageway for air to enter and exit the lungs.

Correct Answer: A

Rationale: The correct answer is A: Skin. An organ is a group of tissues that work together to perform specific functions in the body. Skin is the body's largest organ, made up of different layers that serve various functions like protection, sensation, and regulation of body temperature. Neuron (B) is a cell type, brainstem (C) is a part of the brain, and DNA (D) is a molecule, not an organ. Skin best fits the definition of an organ, making it the correct choice.

Correct Answer: D

Rationale: The correct answer is D: Type O. Type O blood lacks both A and B antigens, making it compatible with all blood types. As a result, it can be safely transfused to individuals with any blood type, earning it the title of the universal donor. Choice A (Type A) has A antigens, Choice B (Type B) has B antigens, and Choice C (Type AB) has both A and B antigens, making them not suitable for universal donation.