Neurobiology III ( Lecture 21 - 23)

Question 1

What is the PNS in charge of

Answer 1

transmitting signals from the CNS to effector parts of the body

Question 2

Branch out the PNS and name their functions

Answer 2

PNS

• — Somatic
• ——- Skeletal system
• — autonomic
• ——- Sympathetic (excitement or activity)
• ——- Parasympathetic ( resting )

Question 3

Cell bodies of somatic neurons are located at the ______

Answer 3

spinal cord

Question 4

(T/F) somatic motor neurons (myelinated) leave the CNS and pass other synapses to skeletal muscles

Answer 4

False

Somatic Motor Neurons leave the CNS and pass without any synapses to skeletal muscles

Question 5

Somatic Motor Neurons release the neurotransmitter _____

Answer 5

Ach ( Acetylcholine)

Question 6

Excitation of motor neurons leads to _______ of skeletal muscles ONLY

Answer 6

contraction.

In order to cause relaxation, inhibition of motor neurons are needed in the spinal cord

Question 7

The Autonomic NS is made up of _____ (#) neurons in series that connect the _____ and ______ cells.

Answer 7

two

CNS and effector cells

Question 8

The first and second neuron bodies of the autonomic neurons are located at ? (1) (2)

Answer 8

(1) CNS

(2) autonomic ganglion

Question 9

What is the neurotransmitter released between pre and postganglionic neurons

Answer 9

ACh

Question 10

(T/F) the signal from postganglionic fiber sent to effectors can only be excitatory

Answer 10

False. Signals from the postganglionic fiber to the effectors can be both excitatory and inhibitory

Question 11

What neurotransmitter is released between postganglionic neurons and target?

Answer 11

This differs between the parasympathetic and sympathetic system

Question 12

What is Dual innervation ?

Answer 12

both the parasympathetic and sympathetic system innervate most organs

Question 13

What is the sympathetic NS responsible for

Answer 13

it is responsible for fight or flight / excitation & physical activities

Question 14

What is the parasympathetic NS responsible for

Answer 14

responsible for rest & digest. // stimulates digestion and slows down cardiac heart rate

Question 15

(T/F) Neurons of the sympathetic and parasympathetic divisions leave the CNS the same level.

Answer 15

False. They leave at different levels

Question 16

What region does the sympathetic fibers exit the CNS

Answer 16

The sympathetic fibers leave the CNS at the lumbar and thoracic regions

Question 17

What region does the parasympathetic fibers exit the CNS

Answer 17

the parasympathetic fibers leave the CNS at the brainstem and sacral regions

Question 18

How does the sympathetic fibers leave the CNS (Explain)

Answer 18

Sympathetic fibers leave the CNS through the lumbar ad thoracic region.
Sympathetic ganglias lie close to the spinal cord and forms 2 chains of ganglia called the sympathetic trunks

Question 19

How does the parasympathetic fibers leave the CNS (Explain)

Answer 19

Parasympathetic fibers leave the CNS at the brainstem and sacral region.
Parasympathetic ganglions are usually located near organs that the postganglionic neurons can innervate

Question 20

One important cranial neuron from the parasympathetic NS is the _______. It originates from the _______ and carries about ____% of all parasympathetic fibers.

Answer 20

vagus nerve
medulla oblongata
75%

Question 21

The ______ is a modified sympathetic ganglion

Answer 21

adrenal medulla

Question 22

Explain the adrenal medulla pathway

Answer 22

1) preganglionic sympathetic cord projects from the spinal cord to the adrenal medulla where they synapse
2) The pregonglionic sympathetic cord produces ACh at the on to chromaffin cells in the adrenal medulla
3) Chormaffic cells are postganglionic specialized cells that lack axons. Once they are stimulated, the release catecholamines directly into the blood.

Question 23

In the Somatic branch of the PNS, the neurotransmitters released between the somatic motor neuron and effectors is _______

Answer 23

Acetylcholine (ACh)

Question 24

The neurotransmitter ______ is also used between the pre and postganglionic neurons in both the ________ and _______ branches of the autonomic NS

Answer 24

ACh

parasympathetic and sympathetic

Question 25

Neurotransmitter between parasympathetic postganglionic neurons and effects is the _____

Answer 25

AcH

Question 26

Neurotransmitter between sympathetic postganglionic neurons and effects are _____ or ________

Answer 26

Epinephrine or Norepinephrine

Question 27

What are Agonists

Answer 27

molecules that bind to receptors and trigger signaling pathways

Question 28

What are antagonists

Answer 28

molecules that bind to receptors but do not trigger signaling pathways

Question 29

The __________ is found in the ______ NS and responds to nicotine found in tobacco products. It is also found between the ______ and _______ in the ______ system.

Answer 29

Nicotine ACh-R Somatic pre and post ganglionic receptors Autonomic NS

Question 30

The ______ is found in the autonomic NS and responds to the mushroom poison, muscarine.

Answer 30

Muscarinic AChR

Question 31

_______ is a competitive ______ of M-AchR

Answer 31

Atropine | antagonist

Question 32

Adrenergic receptors of which many subtypes exist are activated by ________

Answer 32

catecholamines

Question 33

Receptor ______ expressed by a target cell determines the cell's response to a signal An example would be _____ receptors that are activated by ______.

Answer 33

subtypes Androgenic catecholamines

Question 34

(T/F) There are cells in the body with no charge

Answer 34

False | All cells in the body have a slight charge

Question 35

Within the Intracellular Fluid, _____ is a major cation

Answer 35

Potassium (K+)

Question 36

Within the Extracellular Fluid, ______ is a major cation

Answer 36

Sodium ( Na+)

Question 37

In the intracellular fluid, ______ and _______ are the major anion

Answer 37

phosphate ions and negatively charged proteins

Question 38

In the extracellular fluid, ______ is the major anion

Answer 38

Chlorine (Cl-)

Question 39

The intracellular fluid is slightly _______.

Answer 39

negative

Question 40

The extracellular fluid is slightly ______

Answer 40

positive

Question 41

The 2 compartments exist in a state of _____________

Answer 41

electrical disequilibrium

Question 42

What is the Law of Conservation of electrical charges

Answer 42

The net amount of electrical charges produced within the cell is 0. The human body is overall electrically neutral

Question 43

(T/F) The phospholipid bilayer of the artificial cell is permeable to ions

Answer 43

False | The phospholipid bilayer of artificial cell is not permeable to ions

Question 44

What is an electrical gradient

Answer 44

When the electrical net charge between the intracellular and extracellular ion is different

Question 45

What is an concentration gradient

Answer 45

When there is one more positive ion outside the cell compared to the inside

Question 46

(T/F) Electrical gradients are measured on an absolute scale

Answer 46

False. Electrical gradients are normally measured on a relative scale.

Question 47

Explain the difference between an absolute scale vs relative scale

Answer 47

Absolute scale involves the counting the number of ions on either side of the membrane. Relative scale involves counting the difference in charge between two points.

Question 48

Neurons and muscle cells typically have a resting potential of ____ to _____ mV

Answer 48

-40 to -90 mV