INI-CET 2025 - Anatomy Practice Questions

Q: Which muscles are supplied by the superficial peroneal nerve?

Peroneus longus & Brevis. ***Peroneus longus & Brevis*** - The **superficial peroneal nerve** (superficial fibular nerve) supplies **only two muscles**: **Peroneus longus** and **Peroneus brevis** - These muscles form the **lateral compartment of the leg** - They function primarily in **ankle eversion** and contribute to **plantar flexion** - The superficial peroneal nerve is a terminal branch of the **common peroneal nerve** that arises at the neck of the fibula *Incorrect - Both A & C* - This option incorrectly combines different muscle groups - Option C refers to muscles supplied by the **deep peroneal nerve**, not the superficial peroneal nerve *Incorrect - Extensor hallucis longus* - This muscle is located in the **anterior compartment** of the leg - It extends the great toe and assists in ankle dorsiflexion - It is innervated by the **deep peroneal nerve**, NOT the superficial peroneal nerve *Incorrect - Peroneus tertius* - This muscle belongs to the **anterior compartment** despite its name - It acts as a dorsiflexor and evertor of the foot - It is supplied by the **deep peroneal nerve**, NOT the superficial peroneal nerve - The superficial peroneal nerve only supplies the lateral compartment muscles (Peroneus longus and brevis)

Q: Identify the region indicated by the number 3 in the given image.

Back of neck. ***Back of neck*** - The number 3 indicates the **squamous part** of the **occipital bone**, which forms the posterior base of the cranium. This region corresponds externally to the upper part of the back of the neck and the back of the head. - This area includes landmarks like the **external occipital protuberance** and **superior nuchal line**, which serve as attachment points for major neck muscles like the **trapezius**. *Ear* - The structures of the ear are associated with the **temporal bone**, which is located lateral to the occipital bone shown in the image. - Region 3 is situated at the posterior midline, far from the lateral position of the ears. *Vertex* - The **vertex** is the most superior point of the skull, located at the junction of the **sagittal** and **coronal sutures**. - The image displays an inferior view of the skull base, which is anatomically opposite to the superiorly located vertex. *Forehead* - The forehead is formed by the **frontal bone**, which constitutes the anterior part of the cranium. - Region 3 is located at the posterior aspect of the skull, making it the anatomical opposite of the forehead.

Q: What is the action of the muscle marked in the image?

Hip abduction. ***Hip abduction*** - The image displays the **gluteus medius** muscle, whose primary action is to **abduct** the thigh at the hip joint. - This muscle is crucial for stabilizing the pelvis during the gait cycle; weakness leads to a positive **Trendelenburg sign**. ***Internal rotation*** - While the anterior fibers of the **gluteus medius** contribute to internal rotation, it is not its primary function. - The primary internal rotators of the hip are the **gluteus minimus** and the **tensor fasciae latae**. ***Knee extension*** - The **gluteus medius** does not cross the knee joint and therefore has no action on knee extension. - Knee extension is the primary function of the **quadriceps femoris** muscle group, located in the anterior thigh. ***Knee flexion*** - The **gluteus medius** does not act on the knee joint, so it cannot cause knee flexion. - Knee flexion is primarily performed by the **hamstring muscles** (biceps femoris, semitendinosus, and semimembranosus) located in the posterior thigh.

Q: Which nerve is not related to olfaction?

Hypoglossal. ***Hypoglossal (Correct Answer)*** - The **Hypoglossal nerve (CN XII)** is a **purely motor nerve** that innervates the intrinsic and extrinsic muscles of the tongue. - It has **no sensory function** and is **not related to olfaction** in any way. - It does not contribute to smell, taste, or nasal sensation. *Trigeminal (Incorrect)* - The **Trigeminal nerve (CN V)**, particularly its ophthalmic (V1) and maxillary (V2) divisions, provides **general sensory innervation to the nasal mucosa**. - It mediates sensations of **irritation, burning, and cooling** from chemical stimuli (chemesthesis) in the nasal cavity, which accompanies the olfactory experience. - While not true olfaction, it contributes to the overall nasal sensory experience alongside CN I (olfactory nerve). *Glossopharyngeal (Incorrect)* - The **Glossopharyngeal nerve (CN IX)** provides **taste sensation** from the posterior third of the tongue [1]. - While primarily involved in taste (gustation) rather than olfaction, taste and smell are closely integrated in **flavor perception** [1]. - This question tests the distinction between nerves directly involved in nasal/smell sensation versus purely motor nerves. *Vagus (Incorrect)* - The **Vagus nerve (CN X)** provides **taste sensation** from the epiglottis and pharynx. - Like CN IX, it contributes to **flavor perception** through the integration of taste and smell [1]. - It has sensory components related to the aerodigestive tract, making it more related to the broader sensory experience than the purely motor hypoglossal nerve. **Key Concept:** Only the **olfactory nerve (CN I)** is responsible for true olfaction [2]. Among the options given, Hypoglossal is the only purely motor nerve with no sensory role in smell, taste, or nasal sensation.

Q: Which muscles are supplied by the ulnar nerve?

All of the options. ***All of the options*** - The **ulnar nerve** supplies the **intrinsic muscles of the hand**, excluding the three thenar muscles (Abductor pollicis brevis, Flexor pollicis brevis-superficial head, Opponens pollicis) and the lateral two lumbricals (1st and 2nd). - The complete list of intrinsic hand muscles supplied by the ulnar nerve includes all interossei (dorsal and palmar), the hypothenar muscles (Abductor digiti minimi, Flexor digiti minimi brevis, Opponens digiti minimi), the third and fourth lumbricals, the palmaris brevis, the adductor pollicis, and the deep head of the flexor pollicis brevis [1]. *Dorsal interossei* - There are four **dorsal interossei** muscles, responsible for **ABduction** (DAB) of the fingers. - All four dorsal interossei are solely supplied by the **deep branch of the ulnar nerve**. *4th lumbrical* - The **lumbricals** are small muscles that flex the MCP joints and extend the IP joints [1]. - The **medial two lumbricals** (3rd and 4th) are supplied by the **deep branch of the ulnar nerve**, while the lateral two are supplied by the median nerve. *Abductor digiti minimi* - This is one of the three **hypothenar muscles** (muscles of the little finger eminence). - Like the other hypothenar muscles, it is exclusively supplied by the **deep branch of the ulnar nerve** [1].

Question 1

Which muscles are supplied by the superficial peroneal nerve?

Accepted Answer

Peroneus longus & Brevis

Answer

Both A & C

Answer

Extensor hallucis longus

Answer

Peroneus tertius

Question 2

Identify the region indicated by the number 3 in the given image.

Accepted Answer

Back of neck

Answer

Vertex

Answer

Forehead

Answer

Ear

Question 3

What is the action of the muscle marked in the image?

Accepted Answer

Hip abduction

Answer

Internal rotation

Answer

Knee flexion

Answer

Knee extension

Question 4

A 35-year-old man presents to the emergency department with a complaint of food stuck in his throat. On examination, a bone is seen in the left piriform recess. Which of the following is most likely to be impaired?

Accepted Answer

Gag reflex

Answer

Cough reflex

Answer

Salivation

Answer

Mastication

Question 5

Which nerve is not related to olfaction?

Accepted Answer

Hypoglossal

Answer

Trigeminal

Answer

Glossopharyngeal

Answer

Vagus

Question 6

Which muscles are supplied by the ulnar nerve?

Accepted Answer

All of the options

Answer

Dorsal interossei

Answer

4th lumbrical

Answer

Abductor digiti minimi

INI-CET 2025 — Anatomy