Human Anatomy and Physiology Diagnostic Flashcards

Which muscle acts as the primary hip flexor during a high knee drill?

Answer: Iliopsoas

The iliopsoas is the strongest and most powerful hip flexor, responsible for the majority of hip flexion force during high-knee movements.

Which type of muscle fiber is most fatigue-resistant and primarily recruited during low-intensity, long-duration activities?

Answer: Type I

Type I (slow-twitch) fibers have high oxidative capacity and many mitochondria, making them highly fatigue-resistant and ideal for aerobic endurance activities.

The sinoatrial (SA) node is located in which chamber of the heart?

Answer: Right atrium

The SA node is embedded in the wall of the right atrium near the opening of the superior vena cava and initiates each cardiac cycle.

During elbow flexion, the brachialis muscle acts on which joint structure?

Answer: Coronoid process of the ulna

The brachialis inserts on the coronoid process and tuberosity of the ulna, making it a pure elbow flexor regardless of forearm rotation.

Which hormonal response to acute resistance exercise primarily promotes muscle protein synthesis?

Answer: Insulin-like growth factor-1 (IGF-1)

IGF-1 stimulates satellite cell activation and protein synthesis pathways, making it a key anabolic signal following resistance training.

The posterior longitudinal ligament runs along which surface of the vertebral bodies?

Answer: Posterior surface of vertebral bodies inside the spinal canal

The posterior longitudinal ligament runs along the posterior surface of the vertebral bodies within the spinal canal, providing some resistance to disc herniation.

Which term describes the curved, S-shaped spine viewed from the sagittal plane in a healthy adult?

Answer: Lordotic-kyphotic curvature

A healthy adult spine has cervical and lumbar lordosis (anterior curves) and thoracic and sacral kyphosis (posterior curves), forming an S-shape in the sagittal view.