Unit 2

Question 1

What is plasticity?

Answer 1

changes in circuit connection and response due to past experience. (adaptation)

Question 2

What is the difference between affective behaviors and cognitive behaviors?

Answer 2

Affective behaviors are related to emotions while cognitive behaviors are related to thinking.

Question 3

What is unique about the human cerebrum?

Answer 3

The cerebrum, or forebrain, is what allows most higher thinking of humans. Cerebrum is grooved and ridged.

Question 4

What is gray matter?

Answer 4

What we typically think of when we think of “brain goo.” Consists of unmyelinated cell bodies, axons, dendrites.

Question 5

What is white matter?

Answer 5

White matter is myelinated axons, mostly. Very few cell bodies. (think “fat”)

Question 6

What are tracts?

Answer 6

The CNS equivalent of the nerves of the PNS. (Bundles of axons).

Question 7

What is the order of the meninges from outer most to inner most?

Answer 7

Dura mater–> arachnoid membrane–> pia mater.

Question 8

What is the dura mater?

Answer 8

The thickest of the meninges. (like a ziploc bag). Has sinuses for the blood leaving the brain

Question 9

What is the arachnoid mater?

Answer 9

The web-like highly vascularized space. Has a subarachnoid space with arachnoid villa that project into dural sinus and allow CSF to enter blood

Question 10

What is the pia mater?

Answer 10

The thin, innermost meninges. It is also vascularized. In close contact with ependymal cells. Layer associated with arterial blood supply to brain

Question 11

What is cerebrospinal fluid? What is it produced by?

Answer 11

CSF is a salty ECF solution secreted by the choroid plexus on the walls of the ventricles. Serves as a shock absorber and chemical protection

Question 12

What is the blood-brain-barrier?

Answer 12

Allows for protection from contaminants in the blood. Prevents water-soluble susbstances from crossing.

Question 13

What are the anatomical and physiological factors that make up the blood-brain barrier?

Answer 13

anatomical: tight junctions between capillaries
physiological: water soluble substances can’t easily cross, whereas lipid soluble can. (why drugs are lipid soluble).

Question 14

Which areas of the brain lack a functional blood brain barrier, and why?

Answer 14

1. medulla oblongata- has a vomiting center in response to toxic substances
2. hypothalamus- releases hormones that must past into capillaries.

Question 15

What is the primary fuel of the brain for energy production?

Answer 15

Glucose. The brain can not resort to anaerobic exercise and doesn’t store glucose.

Question 16

What is the dorsal root? What are the dorsal root ganglia?

Answer 16

Dorsal root transmits information from the sensory neurons to the brain. The dorsal root ganglia, swelling on the dorsal roots, contain cell bodies of sensory neurons.

Question 17

What is the ventral root?

Answer 17

The ventral root carries information from the CNS to the muscles and glands.

Question 18

What are the three different horns of the spinal cord?

Answer 18

• *all regions of gray matter
  1. dorsal horn: contains cell bodies of interneurons where afferent neurons terminate.
  2. Lateral Horns: cell bodies of autonomic nerve fibers (smooth/ cardiac muscle, glands)
  3. Ventral horns: contain cell bodies of efferent neurons supplying skeletal muscles

Question 19

What are ascending and descending tracts?

Answer 19

**white matter
Ascending tracts: sensory information relays to the brain
descending tracts: carry mostly efferent (motor) signals from brain to spinal cord.

Question 20

In what way is the organization of the spinal cord like a highway?

Answer 20

2 lanes –> 3 lanes. Organization is conserved. Lower level (ex. foot) more centrally located than upper level (arm).

Question 21

What is the only cranial nerve we are responsible for?

Answer 21

The vagus nerve (#10). It carries both sensory and motor fibers for many internal organs

Question 22

What is the reticular formation responsible for?

Answer 22

The reticular formation is a group of neurons that extends throughout the braint stem. The reticular formation is responsible for arousal, sleep, muscle tone, and pain modulation. (system alert)

Question 23

What is the function of the midbrain?

Answer 23

eye movement

Question 24

What is the function of the pons?

Answer 24

relay between cerebrum and cerebellum, coordination of breathing

Question 25

What is the function of the medulla oblongata?

Answer 25

involuntary movements