Chapter 13

Question 1

What germ layer gives rise to the nervous system?

Answer 1

Ectoderm

Question 2

What does the neural tube differentiate into and the neural crest cells?

Answer 2

Neural tube – brain and spinal cord
Neural crest cells - PNS

Question 3

List the primary vesicles and the part of the brain they develop into; then list the secondary vesicles and where they are derived from.

Answer 3

Primary – prosencephalon (forebrain), mesencephalon (midbrain), rhombencephalon (hindbrain)
Secondary – telencephalon (cerebrum) and diencephalon (thalamus and hypothalamus) derived from prosencephalon; mesencephalon does not differentiate; metencephalon (pons and cerebellum) and myelencephalon (medulla oblongata) derive from the rhombencephalon

Question 4

What function is the dorsal aspect of the spinal cord responsible for? The ventral aspect?

Answer 4

Dorsal/posterior – sensory; ventral/anterior - motor

Question 5

Define the three different types of spina bifida.

Answer 5

Occulta – mildest – vertebral bones do not fully surround spinal cord but spinal cord not affected, no functional differences
Meningocele – meninges protrude through spinal column but nerves are not involved – few symptoms but may have complications later
Myelomeningocele – meninges protrude and spinal nerves involved – severe neuro symptoms present

Question 6

What are the three nuclei found in the cerebrum and what are they involved in?

Answer 6

Basal nuclei – cognitive processing especially associated with planning movements
Basal forebrain – learning and memory
Limbic cortex – part of limbic system – structures involved in emotion, memory, behavior

Question 7

Differentiate between a gyrus and a sulcus.

Answer 7

Gyrus – ridge; sulcus - groove

Question 8

What functions are each lobe of the brain involved in?

Answer 8

Frontal – motor, short-term memory, planning, personality, consciousness, Broca’s area here
Parietal – somatosensation
Temporal – auditory, long-term memory
Occipital – primary visual perception

Question 9

What are the direct and indirect pathways and how does the substantia nigra pars compacta play into it? What about the D1 and D2 receptors?

Answer 9

Direct pathway allows the release of the thalamus from inhibition – leads to movement
Indirect pathway keep thalamus inhibited – no movement
SNc – is the switch between the two pathways
D1 – stimulate direct pathway
D2 – stimulate indirect pathway

Question 10

What structures are considered the diencephalon and what are their functions?

Answer 10

Thalamus – relay center
Hypothalamus – homeostasis, endocrine function, emotion and memory
Epithalamus – pineal gland
Subthalamus – subthalamic nuclei in basal ganglia

Question 11

What composes the brain stem and what is its purpose?

Answer 11

Midbrain, pons, medulla – coordinate sensory representations, regulate crucial functions

Question 12

What information do the inferior and superior colliculi project?

Answer 12

Inferior colliculi – auditory information relayed to thalamus
Superior colliculi - sensory info about visual space, auditory space, somatosensory space

Question 13

The pons serves as a bridge between what two structures?

Answer 13

Bridge between cerebellum and brain stem

Question 14

What is the reticular formation and what is its purpose?

Answer 14

Diffuse gray matter throughout brain stem – sleep and wakefulness – general brain activity and attention

Question 15

What is the cerebellum and what does it do?

Answer 15

The “little brain” located at the posterior aspect of the brain - Compare info from cerebrum with sensory feedback from periphery through spinal cord; send corrective actions

Question 16

What is the Circle of Willis and what is it composed of?

Answer 16

Main circulation in the brain – left and right internal carotid arteries + branches of basilar artery

Question 17

List the three meningeal layers.

Answer 17

Dura mater, arachnoid mater, pia mater

Question 18

How does the CSF flow through the CNS (describe the ventricular system pathway).

Answer 18

Lateral ventricles and dump into 3rd ventricle via intraventricular foramina then into cerebral aqueduct to the 4th ventricle and finally to the central canal

Question 19

List all sympathetic ganglia, and list all parasympathetic ganglia.

Answer 19

Sympathetic – sympathetic chain ganglia, paravertebral ganglia, prevertebral ganglia
Parasympathetic – terminal ganglia

Question 20

List all 12 cranial nerves, their function, and whether they are sensory, motor, or both.

Answer 20

CN I – Olfactory – smell - sensory
CNII – Optic – vision – sensory
CN III – Oculomotor – move eyes –motor
CN IV – Trochlear – move eyes – motor
CN V – Trigeminal – facial sensations, mastication – both
CN VI – Abduens – eye movement – motor
CN VII – Facial – facial expressions, taste, saliva production – both
CN VIII Acoustic/Vestibulocochlear – hearing and balance – sensory
CN IX Glossopharyngeal – muscles of oral cavity and upper throat – both
CN X Vagus – homeostasis – both
CN XI – Spinal accessory – control muscles of neck – motor
CN XII – hypoglossal – control muscles of tongue and lower throat - motor

Question 21

What are the nerves plexuses?

Answer 21

Cervical, brachial, lumbar, sacral