Nervous and Sensory Systems

Question 1

What is essential for coordination of different systems with the nervous system?

Answer 1

synapses

Question 2

What were the first to develop a nerve net?

Answer 2

cnidarians

Question 3

How did the Cambrian Explosion affect the nervous system?

Answer 3

appearance of specialized nervous systems, became more complex

Question 4

What are ganglia?

Answer 4

concentrated regions of neurons evolved with bilateral symmetry, allowing many signals to be compared/processed together

Question 5

What did ganglia lead to?

Answer 5

development of the central nervous system

Question 6

What is cephalization?

Answer 6

clustering sensory organs and interneurons at the front of the body
facilitated evolution of head region, the brain, and the CNS

Question 7

Where is the longitudinal nerve cord located in invertebrates?

Answer 7

ventral (below)

Question 8

Where is the longitudinal nerve cord located in chordates?

Answer 8

dorsal (above) the spinal cord in vertebrates

Question 9

What are nerves?

Answer 9

groups of neurons with similar functions with axons that are bundled together
evolved due to advantage of neurons with similar wiring taking shortest path to target

Question 10

What is a reflex?

Answer 10

the body’s automatic response to certain stimuli

Question 11

What does the CNS consist of?

Answer 11

the brain and spinal cord

Question 12

What does the PNS consist of?

Answer 12

nerves and glangia

Question 13

What is grey matter of the brain?

Answer 13

neuron cell bodies, dendrites, unmyelinated axons

Question 14

What is white matter of the brain?

Answer 14

bundles of nerve fibers with myelinated axons

Question 15

What are the four main areas of the brain?

Answer 15

brainstem
diencephalon
cerebellum
cerebum

Question 16

What is the brainstem?

Answer 16

coordinates and conducts information between brain centers

controls and integrates some basal functions, like respiration and cardiovascular control

Question 17

What is the diencephalon?

Answer 17

neuroendocrine tissue like the hypothalamus, pituitary
regulates homeostasis
basic survival behaviors such as feeding, fighting, fleeing, and reproduction
relay center for the cerebrum

Question 18

What is the cerebellum?

Answer 18

coordination and error checking during motor, perceptual, and cognitive functions.
also involved in learning and remembering motor skills

Question 19

What is the cerebrum?

Answer 19

largest and most complex part of the brain
primary sensory areas where information is integrated
voluntary movement of skeletal muscles
cognitive functions like thought, language, speech, and learning

Question 20

What does vertebrate sensory PNS form from?

Answer 20

neural crest cells: specialized ectodermal cells that develop, separate, and migrate during neural tube formation
form numerous tissues, including sensory neuron in the PNS

Question 21

What does the PNS do?

Answer 21

transmits information to and from the CNS

Question 22

What are cranial nerves?

Answer 22

originate in the brain and mostly terminate in the head and upper body

Question 23

What are spinal nerves?

Answer 23

originate in the spinal cord and extend to parts of the body below the head

Question 24

What are afferent neurons?

Answer 24

transmit information towards the CNS (sensory neurons)

Question 25

What are efferent neurons?

Answer 25

transmit signals away from the CNS (output response neurons)

Question 26

What are mechanosensors?

Answer 26

neurons that have receptors designed to cause a depolarization when there are changes in membrane pressure, vibration, movement

Question 27

What are thermosensors?

Answer 27

specialized membrane proteins that change conformation with temperature

Question 28

What are nociceptors?

Answer 28

detect noxious, chemical (pain receptors)

Question 29

What are gustatory receptors?

Answer 29

neurons with ligand gated ion channels that open in when binding to a particular tastant

Question 30

What are olfactory receptors?

Answer 30

neurons with ligand gated ion channels that open in when binding to a particular odorant

Question 31

What do photoreceptors have? How do they behave?

Answer 31

they have special membrane protein with Rhodopsin

changes shape when light hits it

Question 32

What are the two efferent systems?

Answer 32

Autonomic and Motor

Question 33

What is the Autonomic system?

Answer 33

regulates an organism’s internal environment in an involuntary manner

sympathetic: fight or flight
parasympathetic: promotes rest and digest responses
enteric: controls digestions, pancreas, gallbladder

Question 34

What is the motor system?

Answer 34

carries signals from the CNS, and to the skeletal muscles

under voluntary control