Identify the function of the anatomical structure labelled by the arrow in the image below.
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Options:
explanation: The image shows a basal view of the skull base, with the front of the skull at the top, the occipital bone at the bottom, and the foramen magnum in the centre. The parasympathetic innervation of the heart is provided by the vagus nerve which leaves the skull cavity together with the glossopharyngeal and the accessory nerves through the jugular foramen, an irregular opening found at the junction between the occipital and the temporal bones. However, the blue arrow points to the stylomastoid foramen, a small opening in the inferolateral temporal bone in between the styloid process and the mastoid process.
name: Allows the passage of the nerve providing parasympathetic fibres to the heart
label: d
answer: no
explanation: The image shows a basal view of the skull base, with the front of the skull at the top, the occipital bone at the bottom, and the foramen magnum in the centre. The nerve providing motor supply to the tongue muscles is the hypoglossal nerve, which exists the skull through the hypoglossal canal, an opening within the occipital bone, on the lateral wall of foramen magnum. However, the blue arrow points to the stylomastoid foramen, a small opening in the inferolateral temporal bone in between the styloid process and the mastoid process.
name: Allows the passage of the nerve providing motor supply to the tongue muscles
label: c
answer: no
explanation: The image shows a basal view of the skull base, with the front of the skull at the top, the occipital bone at the bottom, and the foramen magnum in the centre. The sensory innervation of the posterior third of the tongue is provided by the glossopharyngeal nerve (CN IX) which leaves the skull cavity together with the vagus and the accessory nerves through the jugular foramen, an irregular opening found at the junction between the occipital and the temporal bones. However, the blue arrow points to the stylomastoid foramen, a small opening in the inferolateral temporal bone in between the styloid process and the mastoid process.
name: Allows the passage of the nerve providing sensory innervation to the posterior third of the tongue
label: e
answer: no
explanation: The image shows a basal view of the skull base, with the front of the skull at the top, the occipital bone at the bottom, and the foramen magnum in the centre. The cranial nerve providing sensory innervation to the inferior third of the face is the mandibular branch of the trigeminal nerve (CN V), which exits the skull through the foramen ovale of the temporal bone. However, the blue arrow points to the stylomastoid foramen, a small opening in the inferolateral temporal bone in between the styloid process and the mastoid process.
name: Allows the passage of the nerve providing sensory innervation to the inferior third of the face
label: b
answer: no
explanation: The image shows a basal view of the skull base, with the front of the skull at the top, the occipital bone at the bottom, and the foramen magnum in the centre. The blue arrow points to the stylomastoid foramen, a small opening in the inferolateral temporal bone in between the styloid process and the mastoid process. It represents the external opening for the facial nerve which travels from the brainstem into the internal acoustic meatus into the temporal bone and through the stylomastoid foramen to reach the parotid gland where it branches. Its branches provide motor supply to the muscles of facial expression.
name: Allows the passage of the nerve providing motor supply to the muscles of facial expression
label: a
answer: yes

Correct answer: a