NCBTMB Anatomy and Kinesiology 3 — Questions and Answers
Question 1: Which layer of the skin contains the keratinocytes undergoing active mitosis?
- Stratum corneum
- Stratum granulosum
- Stratum spinosum
- Stratum basale (Correct answer)
Correct answer: Stratum basale
The stratum basale (basal layer) contains mitotically active keratinocytes that continuously replenish the upper skin layers.
Question 2: The brachial plexus is formed from which spinal cord levels?
- C4–C8
- C5–T1 (Correct answer)
- C6–T2
- C4–T2
Correct answer: C5–T1
The brachial plexus originates from ventral rami of C5 through T1 and provides all motor and sensory innervation to the upper extremity.
Question 3: During the stance phase of gait, which muscle prevents the pelvis from dropping on the swing-leg side?
- Iliopsoas
- Gluteus maximus
- Gluteus medius (Correct answer)
- Adductor magnus
Correct answer: Gluteus medius
The gluteus medius on the stance-leg side contracts eccentrically to stabilize the pelvis and prevent a contralateral Trendelenburg drop.
Question 4: Which spinal curve is considered a primary curve present at birth?
- Lumbar lordosis
- Cervical lordosis
- Thoracic kyphosis (Correct answer)
- Sacral kyphosis
Correct answer: Thoracic kyphosis
The thoracic and sacral kyphotic curves are primary curves present from fetal development, while cervical and lumbar lordoses develop postnatally.
Question 5: The rotator cuff is composed of which four muscles?
- Supraspinatus, infraspinatus, subscapularis, teres major
- Supraspinatus, infraspinatus, teres minor, subscapularis (Correct answer)
- Deltoid, supraspinatus, infraspinatus, teres minor
- Infraspinatus, teres minor, subscapularis, pectoralis minor
Correct answer: Supraspinatus, infraspinatus, teres minor, subscapularis
The rotator cuff consists of supraspinatus, infraspinatus, teres minor, and subscapularis, remembered by the mnemonic SITS.
Question 6: Which type of cartilage is found in intervertebral discs?
- Hyaline cartilage
- Elastic cartilage
- Fibrocartilage (Correct answer)
- Articular cartilage
Correct answer: Fibrocartilage
Fibrocartilage is found in intervertebral discs, the pubic symphysis, and the menisci; it withstands both compressive and tensile forces.
Question 7: Eversion of the foot is primarily performed by which muscles?
- Tibialis anterior and tibialis posterior
- Peroneus longus and peroneus brevis (Correct answer)
- Extensor digitorum longus and extensor hallucis longus
- Gastrocnemius and soleus
Correct answer: Peroneus longus and peroneus brevis
The peroneus (fibularis) longus and brevis, located in the lateral compartment of the leg, are the primary evertors of the foot.
NCBTMB Anatomy and Kinesiology 3
Which layer of the skin contains the keratinocytes undergoing active mitosis?