Nervous system part 1

Question 1

Afferent neurons are what?

Answer 1

Sensory

Question 2

Efferent Neurons are what?

Answer 2

motor

Question 3

Most nervous system are organized into three divisions

Answer 3

Afferent, Efferent, integration

Question 4

What organisms are the excepton to the three division rule?

Answer 4

Cnidarians

Question 5

Cniarians have what type of nervous system?

Answer 5

Nerve net

neurons are not specialized

Question 6

What is different about Cnidarians AP’s

Answer 6

They travel in both directions

Question 7

What is different about Cnidarians neurons?

Answer 7

not specifically sensory or motor

but can still perform complex behavior

Question 8

Cephalization occurs in most animals and is more apparent in more complex nervous systems what are two exceptions?

Answer 8

Cnidarians and Echinoderms

both lack cephalization

Question 9

What is different about more complex organisms neurons?

Answer 9

they have more neurons and more synapses

Question 10

What does increased synapses allow?

Answer 10

increases number of synapses allow for more integration of information and more complex behaviour

since memories are stored in synapses, a complex nervous system also allows for greater potential for learning

Question 11

The vertebrate central nervous system:

What are some characteristics?

(4)

Answer 11

high degree of cephalization

unique in having a hollow dorsal nerve cord

part of the nervous system is encased within cartilage or bone (CNS-brain and spinal cord)

part of the nervous system extends to the periphery of the body (PNS nerves outside of the CNS)

Question 12

Cranial and spinal nerve:

where does it exit from, how many pairs, what type of signals?

Answer 12

directly from skull

13 pairs

afferent and efferent signals

Question 13

Spinal nerve:

Where does it branch off from?

Answer 13

branch from spinal cord

enter and exit between adjacent vertebrae

named based on region of vertebral column from which they emerge

Question 14

What is grey mater?

Answer 14

neuronal cell bodies

Question 15

What is white matter?

Answer 15

tracts of axons and their myelin sheaths

Question 16

where is the white matter and grey matter located in spinal chord?

Answer 16

white matter on surface and grey matter inside

Question 17

where is the white matter and grey matter located in cerebral cortex

Answer 17

grey matter on surface

white matter inside

Question 18

Characteristics of Meninges?

2

Answer 18

connective tissue that surround brain and spinal cord

number of menings vary across taxa

Question 19

Characteristics of CSF?

Answer 19

fills spaces within the CNS and acts as shock absorber

Question 20

Characteristics of BBB

Answer 20

tight junctions in brain capillary endothelium astrocytes endfeet pericytes limit the passage of solutes from bloodstream into CSF protects brain from harmful substances

transporters for glucose and AA

except pineal gland, pituitary and parts of hypothalamus are permeable

Question 21

What are the three main regions in the brain?

Answer 21

Rhombencephalon (hindbrain)

Mesencephalon (Midbrain)

Prosencephalon (forebrain)

Question 22

What are the ventricals in the brain?

Answer 22

Cavities inside brain filled with CSF

ciliated ependymal cells, lining the ventricles circulate the CSF

Question 23

What are the three regions of the Rhombencephalon ( Hidbrain )

Answer 23

Pons

cerebellum

medula

Question 24

What does the pons do?

Answer 24

located rostral to medulla

pathway between medulla, cerebellum, and forebrain

controls alertness, initiates sleep and dreaming

linked to cerebellum: motor control

Question 25

What is the cerebellum

Answer 25

two hem. at back of brain responsible for motor coordination contains half of the neurons in the brain!! (woah)

Question 26

What are the characteristics of the Medulla?

Answer 26

Located at the top of spinal cord regulates breathing, heart rate, diameter of blood vessels, blood pressure contains pathways from spine to brain many cross overs (L -->R)

Question 27

What is the midbrains function?

Answer 27

Primary center for coordination and initiating reflex responses to auditory and visual information in fish and amphibians

Question 28

What is the inferior colliculi?

Answer 28

Auditory input

Question 29

What is the superior colliculi?

Answer 29

visual input

Question 30

What changes about the midbrain in mammals?

Answer 30

size and function is reduced compared to amphibians

Question 31

What process is the forebrain involved in?

Answer 31

Involved in processing and intergrating sensory info, and coordinating behavior

Question 32

What are the main regions of the forebrain?

Answer 32

limbic system hypothalamus thalamus hippocampus cerebrum

Question 33

What is the Cerebrum? what do the left and right sides do

Answer 33

Outer layer in the cortex divided into two hem. left side- controls right side right side- controls left side neurons innervate the opposite side via corpus callosum

Question 34

What does the hypothalamus do?

Answer 34

Located at base of forebrain (under thalamus) helps maintain homeostasis (Body temp, thirst, hunger) feeding fucking interacts with automonic system regulated secretion via pituitary hormones

Question 35

What does the limbic system do?

Answer 35

network of connected structures that lie between the cortex and the rest of the brain influences emotions, motivation, memory

Question 36

What are the 5 parts that make up the limbic system?

Answer 36

Amygdala- aggression and fear response hippocampus- converts short term memory to long-term memory olfactory bulbs- smell Nucleus accumbens- reward, addiction Cingulate cortex- executive function of brain, decision making, motivation and planning

Question 37

Characteristics of the thalamus?

Answer 37

Large grouping of grey matter above hypothalamus receives input from limbic system and all senses except olfaction relays sensory info to cortex;auditory, visual, somatosensory, visceral major rol in regulating states of sleep and wakefulness

Question 38

What are the characteristics of the cortex?

Answer 38

Intergrates and interprets sensory info initiates voluntary movement has taken over many of the midbrain functions of lower vertebrates Contains ISOCORTEX- necessary for cognition and higher brain functions

Question 39

What are Gyri?

Answer 39

Folds

Question 40

What are sulci?

Answer 40

grooves

Question 41

How many cortical layers? how do the layer differ? where are pyramidal neurons located? what form the local connections?

Answer 41

6 differ in shape and density 2/3, 5, 6 interneurons

Question 42

How are the cortical lobes named?

Answer 42

According to the function or overlying bone of the skull