Lecture Material - CNS & Senses

Question 1

What are the components of the Central Nervous System (CNS)?

Answer 1

brain and spinal cord

Question 1

What does the Peripheral Nervous System (PNS) include?

Answer 1

all neurons outside the central nervous system, including the somatic and autonomic nervous systems.

Question 2

What is the main function of the somatic nervous system?

Answer 2

voluntary actions via skeletal muscles

Question 2

What is the role of the autonomic nervous system?

Answer 2

regulates visceral functions such as heart rate and breathing

Question 3

What is the enteric nervous system?

Answer 3

part of the autonomic system that controls digestion and gut movement.

Question 4

what does white matter consist of?

Answer 4

myelinated axons in bundles called tracts

Question 4

What nervous systems are glia found in and what is their job?

Answer 4

Cells in the CNS and PNS that support and protect neurons.

Question 4

How many neurons are in the spinal cord?

Answer 4

About 1 billion neurons.

Question 5

What are the main components of the CNS?

Answer 5

Gray and white matter

Question 5

How many neurons are estimated to be in the brain?

Answer 5

Approximately 86 billion neurons

Question 6

what does gray matter consist of?

Answer 6

nerve cell bodies, unmyelinated axons, dendrites

Question 7

How does the brain use energy?

Answer 7

The brain is 2% of body mass but receives 15% of blood and consumes half of the body’s glucose.

Question 8

How much energy does the CNS use compared to computers?

Answer 8

The CNS runs on ~40 watts, while computers require much more, like 200,000 watts for complex tasks.

Question 9

What happens during neuronal communication?

Answer 9

Neurons send action potentials spikes

Question 9

how much energy do action potential spikes consume?

Answer 9

a lot

Question 9

How many segments does the spinal cord have?

Answer 9

31 segments

Question 10

What do dorsal roots do?

Answer 10

carry incoming sensory signals

Question 11

What do ventral roots do?

Answer 11

carry outgoing motor signals

Question 12

What shape does the gray matter in the spinal cord take?

Answer 12

It has a butterfly shape with dorsal and ventral horns

Question 12

What is the job of ascending tracts?

Answer 12

carry sensory signals to the brain

Question 13

What types of nuclei are found in the gray matter?

Answer 13

Sensory nuclei (in the dorsal horn) and motor nuclei (in the ventral horn)

Question 14

What is the job of descending tracts?

Answer 14

carry motor signals from the brain

Question 15

What is a spinal reflex?

Answer 15

A quick response to stimuli that occurs without brain involvement

Question 16

How many major divisions does the brain have and what are they?

Answer 16

brain has 6 major divisions: cerebrum, diencephalon, midbrain, cerebellum, pons, and medulla.

Question 16

what is an example of a spinal reflex?

Answer 16

knee-jerk reflex

Question 17

What functions are controlled by the brain stem?

Answer 17

It controls autonomic functions like breathing, swallowing, vomiting, and regulating blood pressure.

Question 18

What does the thalamus do?

Answer 18

It processes information going to and from the cerebral cortex.

Question 19

What is the function of the hypothalamus?

Answer 19

It regulates behavioural drives and autonomic homeostasis.

Question 20

What connects the two hemispheres of the cerebrum?

Answer 20

corpus callosum

Question 21

What is the idea behind cerebral lateralization?

Answer 21

idea that each hemisphere of the brain is geared towards specific functions for example, the left hemisphere is more involved in language.

Question 22

What are the four lobes of each cerebral hemisphere?

Answer 22

Frontal, Parietal, Occipital, and Temporal lobes.

Question 23

What structures are part of the limbic system?

Answer 23

cingulate gyrus, hippocampus, and amygdala

Question 23

What is the limbic system responsible for?

Answer 23

motivation, emotion, and memory