Practice TEAS Science Test

Correct Answer: D

Rationale: The correct answer is D: Epiglottis. The epiglottis is a flap of tissue that covers the opening of the windpipe (trachea) during swallowing to prevent food from entering it. Step-by-step rationale: 1. During swallowing, the epiglottis moves down to cover the trachea. 2. This action directs food to the esophagus (B), a muscular tube that carries food to the stomach. 3. The pharynx (A) is a common passageway for both food and air but does not prevent food from entering the windpipe. 4. The larynx (C) is involved in sound production but does not prevent food from entering the windpipe. In summary, the epiglottis is the correct structure as it specifically functions to protect the windpipe during swallowing, while the other choices do not have this specific function.

Correct Answer: D

Rationale: The correct answer is D because the Vas Deferens connects each testis to the urethra, allowing sperm to travel from the testes to the urethra during ejaculation. This tube plays a crucial role in the male reproductive system by transporting sperm for ejaculation. A is incorrect because the production of fluid to increase sperm mobility is carried out by the seminal vesicles and prostate gland. B is incorrect because the site where the egg matures is the fallopian tubes in females. C is incorrect because controlling urine flow is the function of the urethra and muscles in the bladder, not the Vas Deferens.

Correct Answer: B

Rationale: The correct answer is B: Medulla oblongata. This part of the brain is located in the brainstem and is responsible for controlling vital involuntary functions like breathing, heart rate, and blood pressure. It contains nuclei that regulate these activities and plays a crucial role in maintaining homeostasis. The cerebellum (A) is involved in coordinating movement and balance, the cerebrum (C) is responsible for higher brain functions like thinking and decision-making, and the thalamus (D) acts as a relay center for sensory information. However, they are not directly involved in controlling involuntary actions like breathing and heart rate.

Correct Answer: B

Rationale: The correct answer is B: Protein. Proteins are macromolecules composed of amino acids, which always contain nitrogen in their structure. Amino acids have an amine group (-NH2), which is where the nitrogen is found. Fatty acids (choice A) do not contain nitrogen in their structure. Lipids (choice C) and carbohydrates (choice D) also do not contain nitrogen in their basic structure. Therefore, protein is the only macromolecule among the choices that will always contain nitrogen.

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.