ATI TEAS Science Questions

Correct Answer: A

Rationale: The trachea is the structure that bifurcates into the primary bronchi. The trachea is a tube that carries air to and from the lungs. It divides into the left and right primary bronchi at a specific point called the carina, which then further divide into secondary and tertiary bronchi, leading to the bronchioles. The alveoli are the tiny air sacs at the end of the bronchioles where gas exchange occurs, not the structure that bifurcates into the primary bronchi. Bronchioles are smaller airway branches that come after the bronchi but do not bifurcate into them. The larynx, also known as the voice box, is located above the trachea and is responsible for sound production, not the bifurcation into primary bronchi. Therefore, the correct answer is the trachea.

Correct Answer: B

Rationale: The correct answer is B: Adipose and areolar connective tissue. The hypodermis, also known as the subcutaneous layer, is primarily composed of adipose (fat) and areolar (loose) connective tissue. These tissues provide insulation, cushioning, and energy storage. Epithelial tissue (Choice A) is not a significant component of the hypodermis, as it is mainly found in the epidermis and lining of internal organs. Collagen fibers (Choice C) are more abundant in the dermis, providing strength and support. Dense connective tissue (Choice D) is also present in the dermis but is not a major component of the hypodermis.

Correct Answer: A

Rationale: The correct answer is A: Complement system. The complement system is a vital component of the immune system responsible for destroying pathogens through various mechanisms like promoting inflammation, enhancing phagocytosis, and directly lysing pathogens. Fibrinogen is crucial for blood clotting, the major histocompatibility complex is involved in immune responses, and platelets aid in blood clotting and wound healing. However, none of these directly destroy pathogens as the complement system does.

Correct Answer: A

Rationale: Keratin is indeed a type of structural protein found in the skin, hair, and nails of animals. It provides strength and protection, helping to maintain the overall structure of these tissues. The other choices are incorrect as antigens are not hormonal proteins but rather are involved in immune response, channel proteins are involved in facilitating the transport of ions or molecules across cell membranes, and actin is primarily involved in cell structure and movement, not as a transport protein.

Correct Answer: B

Rationale: The correct answer is B - Hypothalamus. The hypothalamus plays a crucial role in controlling the pituitary gland and regulating essential functions such as hunger, thirst, and body temperature. It acts as a vital link between the nervous system and the endocrine system, contributing to the maintenance of homeostasis in the body. Choice A, the Thalamus, is incorrect as it is primarily involved in relaying sensory information to the cerebral cortex. Choice C, the Medulla oblongata, is not responsible for regulating hunger, thirst, and body temperature; instead, it controls autonomic functions like breathing and heart rate. Choice D, the Cerebellum, is primarily associated with coordination and balance, not the regulation of endocrine functions or basic physiological needs.