NSCA-CPT Human Anatomy and Physiology Diagnostic 5 — Questions and Answers
Question 1: Which spinal vertebral region has the greatest inherent stability due to its articulation with the rib cage?
- Cervical
- Lumbar
- Sacral
- Thoracic (Correct answer)
Correct answer: Thoracic
The thoracic spine is stabilized by the rib cage and costovertebral joints, significantly limiting range of motion compared to the cervical or lumbar regions.
Question 2: The sliding filament theory of muscle contraction describes the interaction between which two proteins?
- Troponin and tropomyosin
- Actin and myosin (Correct answer)
- Titin and nebulin
- Dystrophin and spectrin
Correct answer: Actin and myosin
Actin (thin filaments) and myosin (thick filaments) slide past each other when myosin heads form cross-bridges with actin, shortening the sarcomere.
Question 3: Which metabolic byproduct accumulates in muscle during intense anaerobic glycolysis and contributes to fatigue?
- Lactic acid only
- Hydrogen ions (H+) (Correct answer)
- Carbon dioxide
- Creatine phosphate
Correct answer: Hydrogen ions (H+)
It is the accumulation of hydrogen ions (H+) — not lactate itself — that lowers intracellular pH and impairs muscle contractile function during high-intensity exercise.
Question 4: The femoral nerve innervates which primary muscle group?
- Hamstrings
- Gluteals
- Quadriceps femoris (Correct answer)
- Adductors
Correct answer: Quadriceps femoris
The femoral nerve (L2–L4) innervates the quadriceps femoris group and provides sensory innervation to the anterior thigh and medial leg.
Question 5: Which layer of connective tissue directly surrounds an individual muscle fiber?
- Epimysium
- Perimysium
- Endomysium (Correct answer)
- Fascia
Correct answer: Endomysium
The endomysium is the innermost connective tissue layer, composed of reticular fibers that directly ensheath each individual muscle fiber.
Question 6: Which blood vessel carries oxygenated blood from the lungs back to the left atrium of the heart?
- Pulmonary artery
- Aorta
- Superior vena cava
- Pulmonary vein (Correct answer)
Correct answer: Pulmonary vein
Pulmonary veins are unique among veins because they carry oxygen-rich blood from the lungs to the left atrium, completing pulmonary circulation.
Question 7: Which muscle group performs plantarflexion and is assessed during a single-leg calf raise test?
- Tibialis anterior and extensor digitorum
- Gastrocnemius and soleus (Correct answer)
- Peroneals and tibialis posterior
- Flexor hallucis longus only
Correct answer: Gastrocnemius and soleus
The gastrocnemius and soleus (together called the triceps surae) are the primary plantarflexors and are the target muscles during calf raise assessments.
NSCA-CPT Human Anatomy and Physiology Diagnostic 5
Which spinal vertebral region has the greatest inherent stability due to its articulation with the rib cage?