CRANIAL AND GROSS BRAIN ANATOMY

Question 1

What is a sulcus?

Answer 1

Crevice/ trench on brain surface

Question 2

What is a gyrus?

Answer 2

Ridge on brain surface

Question 3

What are foramina?

Answer 3

Hole to allow structures to pass through

Question 4

What is the choroid plexus?

Answer 4

• Lines ventricle system in the brain
  
  • Produces CSF

Question 5

What is falx cerebri?

Answer 5

longitudinal crescent shaped fold of meningeal layer of dura mater between cerebral hemisphere

Question 6

What is the purpose of the ventricular system?

Answer 6

Communicating cavity filled with CSF

Question 7

Sinus

Answer 7

Cavities filled with air

e.g frontal, sphenoid, ehthmoid and maxillary

Question 8

Sella turcica

Answer 8

Saddle shape depression in sphenoid bone, houses pituitary gland

Question 9

Cerebrum

Answer 9

The cerebrum or telencephalon is a large part of the brain containing the

• cerebral cortex (of the two cerebral hemispheres),
• subcortical structures, including the hippocampus, basal ganglia, and olfactory bulb.

Question 10

What is the hindbrain and what is its function?

Answer 10

Hindbrain is the cerebellum

balance, muscular co ordination and dexterity

Question 11

How many bones form the skull?

How many of these form the cranium and face?

What are the joints between these bones called?

Answer 11

• 22 bones
• 8 form the cranium
• 14 form the face
  
  • Joints between these bones are examples of syndesmosis, fibrous joints

Question 12

What is the telencephalon?

Answer 12

Cerebrum - largest part of the brain

Question 13

What is the brain stem composed of? What are its functions?

Answer 13

Brain stem is composed of the midbrain, pons and medulla oblongata

= critical for normal conscious awareness and basic life support functions, consists

Question 14

What is the diencephalon?

Answer 14

is a division of the forebrain (embryonic prosencephalon), consists of thalamus and hypothalamus

Question 15

What is the Mesencephalon?

Answer 15

Portion of the brainstem that connects the hindbrain and forebrain

Question 16

What is the metencephalon?

Answer 16

embryonic part of the hindbrain that differentiates into the pons and the cerebellum

contains a portion of the fourth ventricle and the trigeminal nerve (CN V), abducens nerve (CN VI), facial nerve (CN VII), and a portion of the vestibulocochlear nerve (CN VIII).

Question 17

Label these regions

Answer 17

Question 18

Identify the fissures on the cerebral hemisphere

Answer 18

• The longitudinal fissure: between the two cerebral hemispheres
• Transverse fissure between the cerebrum and cerebellum

Question 19

What is this structure called?

Answer 19

Lateral Sulcus

• Located between frontal and temporal lobes

Question 20

What does the frontal lobe contain?

Answer 20

Primary motor cortex involved in mood + personality

Question 21

What does the parietal lobe contain?

Answer 21

Primary somatic sensory cortex involved in sensation

Question 22

What does the occipital lobe contain?

Answer 22

Primary visual cortex involved in vision

Question 23

What does the temporal lobe contain?

Answer 23

Primary auditory cortex involved in hearing and emotions

Question 24

What is the structure in pink?

Answer 24

Corpus Callosum = Nerve fibres linking the two cerebral hemispheres

Question 25

What is the tentorium cerebelli?

Answer 25

Second dural partition interposed between the cerebrum and cerebellum

Question 26

What are the different layers of the skull?

Answer 26

* Scalp * Periosteum * Bone/Cranium * Dura Mater (external + internal) * Subdural Space * Arachnoid * Subarachnoid Space * Pia Mater * Cerebrum

Question 27

What are the three sutures on the skull?

Answer 27

Question 28

What forms the blood brain barrier?

Answer 28

**_Arachnoid layer_** ## Footnote Arachnoid granulations which allow for connections between the CSF and blood The **blood brain barrier** is specialized interface between circulating blood and CNS. It helps protect the CNS by only allowing certain types of molecules to pass

Question 29

Describe the ventricular system

Answer 29

* Two lateral ventricles located in the cerebral hemispheres * They span from the frontal to the occipital cortex * drain via **interventricular foramina** to 3rd Ventricle * 3rd Ventricle – bounded by the thalamus and hypothalamus on either side * It communicates with the lateral ventricle via ducts **(aqueduct of Sylvius)** * 4th Ventricle – receives CSF from the third ventricle via the **cerebral aqueduct (Sylvius)** * Lies within the brainstem at the junction between the pons and medulla

Question 30

What is bacterial meningitis?

Answer 30

Acute inflammation of the arachnoid and pia with thick creamy exudate filling subarachnoid space and surrounding vessels

Question 31

What is CSF secreted by and into where?

Answer 31

CSF is secreted by the **_choroid plexus_** through the ventricular system starting from the lateral ventricles to 3rd Ventricle via **_interventricular foramina_** and then from 3rd Ventricle to 4th Ventricle via the **_aqueduct of Sylvius._** CSF will be secreted into the **SUBARACHNOID SPACE**

Question 32

What is CSF reabsorbed into?

Answer 32

CSF is reabsorbed into the **superior sagittal sinus** (one of the dural venous sinuses)

Question 33

Label these regions of the brainstem How many of the cranial nerves are present in the brainstem?

Answer 33

* (Sometimes the diencephalon (thalamus + hypothalamus) is included) 1. Midbrain 2. Pons (in latin means bridge, pons is like the bridge between) 3. Medulla Oblongata 10 (III-XII) of the cranial nerves arise from the brainstem

Question 34

What is the cerebral peduncle?

Answer 34

Located on the midbrain, resembles a roman pillar

Question 35

Which two cranial nerves start in the cerebrum?

Answer 35

1. **_Olfactory Nerve I_** - enters skull through cribiform plate of ethmoid bone - involved in smell 2. **_Optic Nerve II_** - transfers visual information from the retina to visual sensory cortex in occipital lobe

Question 36

What does the vagus nerve do?

Answer 36

* Innervates muscles of speech and swallowing (pharynx + larynx) * Is the parasympathetic nerve of the thorax and abdomen to level of splenic flexure of colon

Question 37

What is parasympathetic innervation after the vagus nerve?

Answer 37

Vagus nerve will only innervate up to the colonic splenic flexure Parasympathetic innervation after this point is through the sacral outflow of the **pelvic splanchnic nerves (S2, 3, 4)**

Question 38

What do these cranial nerves do? * Trigeminal (CNV) * Facial (CNVII) * Spinal Accessory (CNXI) * Vestibulocochlear (CNVIII)

Answer 38

* **Trigeminal (CNV)** * Sensation of the face * **Facial (CNVII)** * Movement of facial muscles and expression * **Spinal Accessory (CNXI)** * Innervates trapezius and sternocleidomastoid * **Vestibulocochlear (CNVIII)** * Transmits sound and balance from the inner ear to the brain

Question 39

What are the bones of the cranium?

Answer 39

occipital bone, two temporal bones, two parietal bones, the **sphenoid, ethmoid** and frontal bones.