WGU D312 ANATOMY AND PHYSIOLOGY PRACTICE QUESTIONS COMPLETE WITH 100% VERIFIED ANSWERS AND RATIONALES

WGU D312 ANATOMY AND PHYSIOLOGY PRACTICE QUESTIONS COMPLETE WITH 100% VERIFIED ANSWERS AND RATIONALES 1. Which of the following structures connects bone to bone? A) Tendons B) Ligaments C) Fascia D) Aponeurosis Correct Answer: B) Ligaments Rationale: Ligaments are dense connective tissue structures that connect bone to bone, providing stability to joints. Tendons connect muscle to bone, fascia surrounds muscles and organs, and aponeurosis is a flat sheet of connective tissue connecting muscle to muscle or bone. ________________________________________ 2. The ethmoid bone serves which primary function in the skull? A) Forms the cheek structure B) Forms the lower jaw C) Separates the nasal cavity from the brain and forms part of the floor of the cranial cavity D) Forms the roof of the nasal cavity Correct Answer: C) Separates the nasal cavity from the brain and forms part of the floor of the cranial cavity Rationale: The ethmoid bone is a delicate bone located between the eyes that separates the nasal cavity from the brain and contributes to the floor of the cranial cavity. The sphenoid bone forms the roof of the nasal cavity, the zygomatic bone forms the cheek structure, and the mandible forms the lower jaw. ________________________________________ 3. Which cells are responsible for forming myelin sheath in the central nervous system? A) Schwann cells B) Satellite cells C) Oligodendrocytes D) Microglia Correct Answer: C) Oligodendrocytes Rationale: Oligodendrocytes are glial cells in the CNS that produce myelin sheaths around multiple axons, increasing the speed of nerve impulse conduction. Schwann cells perform this function in the PNS, satellite cells support PNS cells, and microglia act as immune cells in the nervous system. ________________________________________ 4. The antagonist of the pectoralis major muscle is the: A) Latissimus dorsi B) Deltoid C) Trapezius D) Rhomboid major Correct Answer: B) Deltoid Rationale: The deltoid muscle serves as the antagonist to the pectoralis major for shoulder flexion and extension. The pectoralis major flexes the shoulder while the deltoid extends it. The latissimus dorsi, trapezius, and rhomboid major are not the primary antagonists for this action. ________________________________________ 5. What is the primary function of microglia in the nervous system? A) Form myelin sheath B) Support neurons structurally C) Act as immune cells and tag foreign invaders for destruction D) Line ventricles and create barriers Correct Answer: C) Act as immune cells and tag foreign invaders for destruction Rationale: Microglia are the immune cells of the central nervous system, responsible for identifying and destroying pathogens and cellular debris. Oligodendrocytes form myelin, astrocytes provide structural support and maintain the BBB, and ependymal cells line ventricles. ________________________________________ 6. Which bone forms the upper jaw? A) Mandible B) Zygomatic bone C) Maxillae D) Palatine bones Correct Answer: C) Maxillae Rationale: The maxillae are paired bones that form the upper jaw, containing the upper teeth and contributing to the floor of the orbit and the roof of the mouth. The mandible forms the lower jaw, zygomatic bones form the cheeks, and palatine bones form the posterior hard palate. ________________________________________ 7. The antagonist of the biceps brachii is the: A) Brachialis B) Brachioradialis C) Triceps brachii D) Pronator teres Correct Answer: C) Triceps brachii Rationale: The triceps brachii acts as the antagonist to the biceps brachii for elbow flexion and extension. The biceps brachii flexes the elbow while the triceps brachii extends it. The brachialis assists with elbow flexion, the brachioradialis also flexes the elbow, and the pronator teres pronates the forearm. ________________________________________ 8. Astrocytes perform which of the following functions in the central nervous system? A) Form myelin sheath B) Act as immune cells C) Allow selective permeability at the blood-brain barrier and serve as a source of neural stem cells D) Line ventricles and create barriers