Axial skeleton 2

Question 1

Nasal sinuses

Answer 1

cavities contained within certain bones of the skull that are lined with mucus membranes.

Question 2

Ethmoid sinuses

Answer 2

air cells that lie in the ethmoidal labyrinth of cavities btwn the medial wall of the orbit and lateral walls of the upper nasal cavity.
* Separated from the orbit by the orbital plate of the ethmoid bone.

Question 2

Functions of sinuses

Answer 2

i.To add resonance to the voice
ii.To lighten the head

Question 2

Bones where sinuses are located.

Answer 2

• The frontal bone
• The maxilla
• The ethmoid bone
• The sphenoid

Question 2

What divides the halves of the mandible.

Answer 2

mylohyoid line divides the mandible to upper and lower half( inner surface.)

Question 2

Alveolar process

Answer 2

contains the teeth

Question 2

Mandible

Answer 2

• bone of the lower jaw
• mental foramen lies 2.5 cm laterally from the symphysis menti.

Question 2

Frontal sinuses

Answer 2

• Found between the inner and outer tables of the frontal bone
  above the nose and medial part of orbits.
• Triangular in shape

Question 2

groups of ethmoid air sinuses/cells.

Answer 2

1. anterior group
2. medial group
3. posterior group.

Question 2

what structure is found below the mylohyoid line.

Answer 2

submandibular fossa.

Question 2

Why are frontal sinuses of different sizes.

Answer 2

the septum that divides them does not pass on the midline.

Question 2

Sphenoid sinuses.

Answer 2

• 2 in number on each side of the midline.
• Separated by a thin bony septum.
• Located in the body of the sphenoid behind the upper nasal cavity.
• Superior there’s the sella turcica and the optic chiasm.

Question 2

The orbital process

Answer 2

extends superomedially to contribute to the medial rim of the orbit.

Question 2

The zygomatic process

Answer 2

continuous with the zydomatic arc

Question 2

Maxillary sinuses(antra)

Answer 2

• Largest paranasal sinuses.
• They have a body of 4 processes.
  
  1. Orbital process
  2. Zygomatic process
  3. Alveolar process
  4. The palatine process

Question 2

prominent processes on the ramus.

Answer 2

• Coronoid process
• Condylar process

between them is the mandibular notch.

Question 2

Hyoid bone

Answer 2

U-shaped bone lying below the floor of the mouth at the front of the neck.

Question 3

The palatine process

Answer 3

forms the roof of the mouth and the floor of the nasal cavity’

Question 3

Features that make up the hyoid bone.

Answer 3

• The body
• 2 greater cornua
• 2 lesser cornua

the cornuas are processes

Question 3

Lesser cornua

Answer 3

are attached to the styloid processes by the stylohyoid ligament.

Question 3

Frontal bone

Answer 3

forms the anterior portion of the skull

Question 3

vertical portion of the frontal forms

Answer 3

forehead and the anterior part of the vault

Question 3

Horizontal portions form

Answer 3

roof of the orbits

Question 4

How is the grabella formed

Answer 4

Arches superficial to the orbits that meet to form the grabella.

Question 4

Parietal bone

Answer 4

Has 4 margins and internal and external surfaces

Question 4

margins of the parietal bone.

Answer 4

* The upper margin articulates with the parietal bone of the opposite side at the suture. * The anterior margin articulates with the frontal bone at the coronal suture. * The posterior margin articulates with the occipital bone. * The inferior margin articulates with the greater wings of sphenoid bone.

Question 4

The temporal bone

Answer 4

Forms the lateral walls of the skull.

Question 5

4 parts of the temporal bone

Answer 5

1. The squamous part 2. The petromastoid part 3. The tympanic part 4. Styloid processes

Question 5

The squamous part of the temporal bone.

Answer 5

* Forms the anterior and upper part of the bone. * The superior margin of the articulates with the parietal bone and anteroinferior margin with the greater wing of the sphenoid

Question 6

The squamous part of the occipital

Answer 6

found behind and above the foramen magnum.

Question 6

Occipital bone

Answer 6

* Found at the posterior and inferior part of the cranium. * Encloses foramen magnum

Question 6

The petromastoid part made of

Answer 6

* Mastoid part; Lies behind the external auditory meatus and forms the posterior part of the bone. * The petrous part; Triangular in shape and contains the organs of hearing and balance.

Question 6

styloid process

Answer 6

* The styloid process is a slender pointed process of bone about 2.5 cm long which projects downward and forward between the tympanic plate and the mastoid process.

Question 7

The tympanic part

Answer 7

curved plate of bone which lies in front of the mastoid process and forms most of the bony wall of the external auditory meatus.

Question 8

Parts of the occipital bone

Answer 8

* The squamous part * The basilar part * The 2 condylar parts

Question 8

Condylar parts

Answer 8

* Found on either side of foramen magnum. * On their inferior surfaces are occipital condyles which articulate with the atlas at the atlanto-occipital joint

Question 9

the basilar part.

Answer 9

Rums upwards from the foramen magnum. * below the magnum foramen is the pharyngeal tubercle that attaches the pharynx.

Question 9

The sphenoid bone

Answer 9

* Lies at the base of the skull in anterior to the occipital bone. * It is comprised of a central body with a greater and a lesser wing on either side. * The pterygoid process projects downwards from the junction of the body and each wing.

Question 10

greater wing of sphenoid

Answer 10

made of medial horizontal portion that forms part of the floor of the middle cranial fossa

Question 11

lesser wing of sphenoid

Answer 11

triangular in shape and projects laterally from the upper anterior part of the body of the sphenoid

Question 11

ethmoid bone

Answer 11

composed of an upper horizontal plate called the cribriform plate, a perpendicular plate, and two structures called the ethmoidal labyrinths which extends downwards from the lateral edges of the cribriform plate