Lecture 6 - Introduction to the Skull

Question 1

What are the 5 layers of the scalp?

Answer 1

1. skin
2. connective tissue (dense)
3. aponeurotic layer
4. loose connective tissue
5. pericranium (periosteum)

Question 2

Why does the scalp bleed so much if it is cut?

Answer 2

because the dense connective tissue tends to hold on the vessels open leading to profuse bleeding

Question 3

How many bones are in the neurocranium?

Answer 3

8

Question 4

How many bones are in the viscerocranium?

Answer 4

14

Question 5

What is the calvaria?

Answer 5

skull cap

Question 6

What kind of bones is the neurocranium formed by?

Answer 6

flat and irregular bones

Question 7

How are the bones of the neurocranium joined together by?

Answer 7

fibrous solid joints (sutures)

Question 8

How are the bones of the neurocranium joined together initially during childhood?

Answer 8

by hyaline cartilage

Question 9

What are the 8 bones of the neurocranium?

Answer 9

1. frontal (1)
2. occipital (1)
3. parietal (2)
4. temporal (2)
5. ethmoid (1)
6. sphenoid (1)

Question 10

What are the 4 sutures in the neurocranium?

Answer 10

1. saggital
2. coronal
3. squamosal
4. lambdoid

Question 11

What are the 2 reference points of the sutures of the naurocranium?

Answer 11

bregma and lambda

Question 12

What suture is between the two parietal bones?

Answer 12

the saggital suture

Question 13

Which suture is between the frontal and parietal bones?

Answer 13

the coronal suture

Question 14

Which sutures are between the temporal and parietal bones?

Answer 14

the squamosal sutures

Question 15

Which sutures are between the occipital and parietal bones?

Answer 15

the lambdoid sutures

Question 16

Which two sutures are found in the bregma reference point?

Answer 16

the saggital and coronal sutures

Question 17

Which two sutures are found in the lambda reference point?

Answer 17

the saggital and lambdoid sutures

Question 18

What are the bones of the neonatal neurocranium separated by?

Answer 18

fontanelles

Question 19

When do fontanelles close?

Answer 19

within 18 months after birth

Question 20

What is the pterion?

Answer 20

weak point in the skull where 4 bones form an H-shaped junction

Question 21

What are the 3 cranial fossae?

Answer 21

1. anterior cranial fossa
2. middle cranial fossa
3. posterior cranial fossa

Question 22

Which bones contribute to the anterior cranial fossa?

Answer 22

frontal bone, ethmoid bone, sphenoid bone (body & lesser wings)

Question 23

Which bones contribute to the middle cranial fossa?

Answer 23

sphenoid bone (body & greater wings), temporal bones

Question 24

Which bones contribute to the posterior cranial fossa?

Answer 24

temporal bones and occipital bones

Question 25

What parts of the brain does the anterior cranial fossa contain?

Answer 25

frontal lobes of cerebrum

Question 26

What parts of the brain does the middle cranial fossa contain?

Answer 26

temporal lobes of cerebrum

Question 27

What parts of the brain does the posterior cranial fossa contain?

Answer 27

brainstem and cerebellum

Question 28

What forms most of the floor of the anterior cranial fossa?

Answer 28

the frontal bone (orbital part) and ethmoid bone (cribriform plate)

Question 29

What are the 2 parts of the ethmoid bone?

Answer 29

cribriform plate and crista galli

Question 30

What does the cribriform plate have?

Answer 30

numerous foramina for olfactory nerves

Question 31

Which floors does the sphenoid bone contribute to?

Answer 31

the anterior cranial fossa and middle cranial fossa

Question 32

What are the parts of the sphenoid bone anteriorly? (5)

Answer 32

1. lesser wing 2. greater wing 3. orbital surface 4. pterygoid process 5. superior orbital fissure

Question 33

What are the 4 foramina found on the sphenoid bone?

Answer 33

1. optic canal 2. foreamen rotundum 3. foramen ovale 4. foramen spinosum

Question 34

What are the parts of the sphenoid bone posteriorly? (6)

Answer 34

1. optic canal 2. superior orbital fissure 3. foramen rotundum 4. foramen ovale 5. foramen spinosum 6. sella turcica

Question 35

Where is the pituitary gland located in the sphenoid bone?

Answer 35

in the sella turcica

Question 36

What fossa does the sella turcica contain?

Answer 36

the pituitary/hypophyseal fossa

Question 37

Which 2 parts of the temporal bone contribute to the floor of the middle cranial fossa?

Answer 37

squamous and petrous

Question 38

Which part of the temporal bone contributes to the floor of the posterior cranial fossa?

Answer 38

petrous part

Question 39

Which part of the temporal bone contains the external acoustic meatus?

Answer 39

the tympanic part

Question 39

What are the parts of the temporal bones laterally? (5)

Answer 39

1. zygomatic process 2. mandibular fossa 3. styloid process 4. external acoustic meatus 5. mastoid process

Question 40

What are the 2 bones of the temporal bone?

Answer 40

squamous and petrous

Question 41

Which part of the temporal bone is the internal acoustic meatus found?

Answer 41

in the petrous part

Question 42

Why is the internal acoustic meatus not a continuous tunnel?

Answer 42

because the middle and inner ear structures are in between

Question 43

What is the function of the petrous ridge?

Answer 43

it separates the middle and posterior cranial fossae

Question 44

Which other bone forms the floor of the posterior cranial fossa in addition to the petrous parts of the temporal bones?

Answer 44

the occipital bone

Question 45

What are the parts of the occipital bone superiorly? (3)

Answer 45

1. clivus 2. hypoglossal canal 3. foramen magnum

Question 46

What does the clivus accommodate?

Answer 46

the brainstem (pons)

Question 47

What does the deep cerebellar fossae hold?

Answer 47

the left and right hemispheres of the cerebellum

Question 48

What are the parts of the occipital bone inferiorly?

Answer 48

1. pharyngeal tubercle 2. occipital condyle

Question 49

What is the function of the pharyngeal tubercle?

Answer 49

it suspends the pharynx beneath the skull

Question 50

What does the occipital condyle articulate with?

Answer 50

C1

Question 51

What are the foramina found in the anterior cranial fossa? (1)

Answer 51

cribriform plate (ethmoid bone)

Question 52

What are the foramina found in the middle cranial fossa? (6)

Answer 52

sphenoid bone (5): - optic canal - superior orbital fissure - foramen rotundum - foramen ovale - foramen spinosum foramen lacerum temporal bone (1): - carotid canal

Question 53

What are the foramina found in the posterior cranial fossa? (4)

Answer 53

temporal bone (1): - internal acoustic meatus jugular foramen occipital bone (2): - hypoglossal canal - foramen magnum

Question 54

Which two foramen are formed between bones?

Answer 54

the foramen lacerum and jugular foramen

Question 55

Which bones are between the foramen lacerum?

Answer 55

sphenoid, temporal and occipital bones

Question 56

Which bones are between the jugular foramen?

Answer 56

temporal and occipital bones

Question 57

What are the structures that travel through the jugular foramen?

Answer 57

internal jugular vein + cranial nerves IX, X, XI

Question 58

How many bones is the viscerocranium composed of?

Answer 58

14

Question 59

How many paired bones are there in the viscerocranium?

Answer 59

6

Question 60

How many unpaired bones are there in the viscerocranium?

Answer 60

2

Question 61

Which bone is sometimes included in both neurocranium and viscerocranium?

Answer 61

ethmoid

Question 62

What are the bones of the viscerocranium?

Answer 62

1. nasal bones (2) 2. lacrimal bones (2) 3. zygomatic bones (2) 4. inferior nasal conchae (2) 5. vomer (1) 6. maxillae (2) 7. mandible (1) 8. palatine (2)