Superior rectus helps in:

 # Superior rectus helps in all of the following movements EXCEPT:

A. Upward rotation

B. Lateral rotation

C. Intorsion

D. Medial rotation

The correct answer is B. Lateral rotation. 

All the rectus muscles are involved in medial rotation of eye except the lateral rectus. Lateral rectus is the only rectus muscle involved in lateral rotation. 

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Muscles is involved in elevation of the eyeball

 # Which of the following group of muscles is involved in elevation of the eyeball?

A. Superior rectus and inferior oblique

B. Inferior rectus and Superior oblique

C. Superior Oblique and superior rectus

D. Inferior oblique and Inferior rectus

The correct answer is : A. Superior rectus and inferior oblique

Action of Individual Muscles:

Levator Palpebrae superioris - Elevation of upper eyelid

Superior rectus - Upward rotation, medial rotation and intorsion

Inferior rectus- Downward rotation, medial rotation and extorsion

Medial rectus- Medial rotation

Lateral rectus- Lateral rotation

Superior oblique- Downward rotation, lateral rotation and intorsion 

Inferior oblique- Upward rotation and extorsion

Single movements of eyeball and muscles involved:

Upward rotation (Elevation)- Superior rectus and inferior oblique

Downward rotation (Depression)- Inferior rectus and Superior oblique

Medial rotation (Adduction)- Medial rectus, Superior rectus and Inferior rectus

Lateral rotation (Abduction)- Lateral rectus, Superior oblique and inferior oblique

Intorsion- Superior rectus and superior oblique

Extorsion- Inferior oblique and Inferior rectus

Nasolacrimal duct is directed:

 # Nasolacrimal duct is directed:

A. Downward, medially, backwards

B. Downward, laterally, backwards

C. Downward, laterally, forward

D. Downward, medially, forward

The correct answer is: B. Downward, laterally, backwards

Nasolacrimal duct: The groove for nasolacrimal duct is located medially near the orbital margin. It is a membranous passage of 18 mm length. It begins at the lower end of the lacrimal sac, runs downwards, backwards and laterally, and opens into the inferior meatus of the nose. A fold of mucous membrane called the valve of Hasner forms an imperfect valve at the lower end of the duct. 

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Stapedius muscle has its nerve supply from:

 # Stapedius muscle has its nerve supply from:

A. Trigeminal nerve

B. Facial nerve

C. Glossopharyngeal nerve

D. Stato-acoustic nerve

The correct answer is: B. Facial nerve

Stapedius muscle along with the tensor tympani are muscles of ossicles of middle ear. Stapedius is supplied by facial nerve, whereas tensor tympani is supplied by mandibular nerve. Stapedius and tensor tympani both act simultaneously to damp down the intensity of high pitched sound waves, thus protecting the internal ear. In paralysis of the muscle even normal sounds appear too loud, which is known as "hyperacusis". 

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