USMLE Step 1 (Human Anatomy) Exam
Questions And Correct Answers (Verified
Answers) Plus Rationales 2025/2026 Q&A |
Instant Download Pdf
1. The brachial plexus is formed from which spinal nerve roots?
A) C1–C5
B) C5–T1
C) C3–C7
D) T1–T5
The brachial plexus is formed by the ventral rami of spinal nerves C5
through T1, supplying the upper limb.
2. Which muscle is primarily responsible for shoulder abduction?
A) Subscapularis
B) Latissimus dorsi
C) Deltoid
D) Pectoralis major
The deltoid abducts the arm beyond the first 15° initiated by the
supraspinatus.
3. The femoral triangle contains all of the following EXCEPT:
A) Femoral artery
B) Femoral vein
C) Femoral nerve
D) Sciatic nerve
The sciatic nerve passes posteriorly; the femoral triangle contains the
femoral nerve, artery, vein, and lymphatics.
,4. The carpal tunnel contains all of the following EXCEPT:
A) Median nerve
B) Flexor digitorum superficialis tendons
C) Flexor pollicis longus tendon
D) Ulnar nerve
The ulnar nerve passes outside the carpal tunnel through Guyon’s
canal.
5. Which cranial nerve exits the skull via the foramen rotundum?
A) V1 (Ophthalmic)
B) V2 (Maxillary)
C) V3 (Mandibular)
D) VII (Facial)
The maxillary branch of the trigeminal nerve (V2) exits via the
foramen rotundum.
6. The spinal cord terminates as the conus medullaris at which
vertebral level in adults?
A) L1–L2
B) L1–L2
C) T12–L1
D) L3–L4
In adults, the spinal cord ends around the L1–L2 vertebral levels;
below this is the cauda equina.
7. Which artery is the main blood supply to the femoral head?
A) Obturator artery
B) Profunda femoris artery
, C) Medial circumflex femoral artery
D) Lateral circumflex femoral artery
The medial circumflex femoral artery supplies the majority of the
femoral head; damage can lead to avascular necrosis.
8. The primary flexor of the forearm at the elbow is:
A) Triceps brachii
B) Brachioradialis
C) Brachialis
D) Pronator teres
The brachialis inserts on the ulna and is the strongest flexor
regardless of forearm position.
9. Which of the following passes through the greater sciatic
foramen?
A) Obturator nerve
B) Sciatic nerve
C) Femoral nerve
D) Lateral femoral cutaneous nerve
The sciatic nerve exits the pelvis through the greater sciatic foramen.
10. The triangular space of the shoulder contains:
A) Axillary nerve
B) Circumflex scapular artery
C) Radial nerve
D) Subscapular nerve
The triangular space transmits the circumflex scapular artery; the
axillary nerve passes through the quadrangular space.
Questions And Correct Answers (Verified
Answers) Plus Rationales 2025/2026 Q&A |
Instant Download Pdf
1. The brachial plexus is formed from which spinal nerve roots?
A) C1–C5
B) C5–T1
C) C3–C7
D) T1–T5
The brachial plexus is formed by the ventral rami of spinal nerves C5
through T1, supplying the upper limb.
2. Which muscle is primarily responsible for shoulder abduction?
A) Subscapularis
B) Latissimus dorsi
C) Deltoid
D) Pectoralis major
The deltoid abducts the arm beyond the first 15° initiated by the
supraspinatus.
3. The femoral triangle contains all of the following EXCEPT:
A) Femoral artery
B) Femoral vein
C) Femoral nerve
D) Sciatic nerve
The sciatic nerve passes posteriorly; the femoral triangle contains the
femoral nerve, artery, vein, and lymphatics.
,4. The carpal tunnel contains all of the following EXCEPT:
A) Median nerve
B) Flexor digitorum superficialis tendons
C) Flexor pollicis longus tendon
D) Ulnar nerve
The ulnar nerve passes outside the carpal tunnel through Guyon’s
canal.
5. Which cranial nerve exits the skull via the foramen rotundum?
A) V1 (Ophthalmic)
B) V2 (Maxillary)
C) V3 (Mandibular)
D) VII (Facial)
The maxillary branch of the trigeminal nerve (V2) exits via the
foramen rotundum.
6. The spinal cord terminates as the conus medullaris at which
vertebral level in adults?
A) L1–L2
B) L1–L2
C) T12–L1
D) L3–L4
In adults, the spinal cord ends around the L1–L2 vertebral levels;
below this is the cauda equina.
7. Which artery is the main blood supply to the femoral head?
A) Obturator artery
B) Profunda femoris artery
, C) Medial circumflex femoral artery
D) Lateral circumflex femoral artery
The medial circumflex femoral artery supplies the majority of the
femoral head; damage can lead to avascular necrosis.
8. The primary flexor of the forearm at the elbow is:
A) Triceps brachii
B) Brachioradialis
C) Brachialis
D) Pronator teres
The brachialis inserts on the ulna and is the strongest flexor
regardless of forearm position.
9. Which of the following passes through the greater sciatic
foramen?
A) Obturator nerve
B) Sciatic nerve
C) Femoral nerve
D) Lateral femoral cutaneous nerve
The sciatic nerve exits the pelvis through the greater sciatic foramen.
10. The triangular space of the shoulder contains:
A) Axillary nerve
B) Circumflex scapular artery
C) Radial nerve
D) Subscapular nerve
The triangular space transmits the circumflex scapular artery; the
axillary nerve passes through the quadrangular space.
