animal physiology: responding to stimuli

Question 1

Responding usually takes three steps:

Answer 1

Senses to detect
Interpret analyze and decide what to do
systems that can cause change

Question 2

All of life strives for

Answer 2

homeostasis

Question 3

What are some factors that can affect homeostasis

Answer 3

pH, temperature, O2 and CO2 levels, glucose

Question 4

What are some systems that can contribute to homeostasis

Answer 4

1. respiratory and cardio- levels of CO2 and O2
2. renal- kidneys and bladder, controls water amounts
3. gastrointestinal- blood sugar
4. nervous and endocrine- controls all three, main controller of homeostasis

Question 5

Negative feedback

Answer 5

most common, corrects the original stimulus

Question 6

Name the pathways of negative feedback and the process

Answer 6

variable –> sensor –> comparer –> reference input (good match) or controller (bad match)

Question 7

If they signal is sent to the controller and is a bad match it is sent back to the

Answer 7

original variable

Question 8

negative feedback restores homeostasis in the

Answer 8

opposite direction

Question 9

Positive feedback

Answer 9

less common, increases original stimuli

Question 10

give two examples of positive feedback

Answer 10

1. giving birth- increases contractions will cause birth

2. fever- increasing body temp fights infections

Question 11

Name the two types of stimuli

Answer 11

external and internal stimuli

Question 12

external stimuli are also called

Answer 12

exteroceptors

Question 13

external stimuli

Answer 13

face out, the five senses, respond to the external environment

Question 14

internal stimuli are also called

Answer 14

interoceptors

Question 15

internal stimuli

Answer 15

face in, blood pressure, body temp

Question 16

Name the four types of receptors

Answer 16

1. chemoreceptors
2. mechanoreceptors
3. photoreceptors
4. thermoreceptors

Question 17

the nervous system is composed of two parts

Answer 17

Central nervous system- brain and spinal cord

Peripheral nervous system- nerves and ganglia

Question 18

the CNS is _____ and the PNS is ____

Answer 18

internal, external

Question 19

neurons are living ____. They contain the ___, ____, ___. Give the function of each

Answer 19

cells
cell body- nucleus and ER, takes signals in and sends them down
axon- sends info out
dendrites- receives info in

Question 20

axon terminals

Answer 20

ends of neurons that signal to others

Question 21

synapse

Answer 21

very small gap between the axon of one neuron and the dendrites of another

Question 22

Name the four types of neurons

Answer 22

1. bipolar- the most common, receives info and makes decisions
2. unipolar- cell body not in line, quick response, hot pan example
3. multipolar- multiple dendrite sites
4. pyrimdal- brain and memory storage, long dendrites

Question 23

The function of sensory neurons

Answer 23

send info from sensory receptors to CNS

Question 24

the function of interneuron neurons

Answer 24

info from CNS to the motor neurons

Question 25

motor neurons function

Answer 25

CNS impulses to effector (gland or muscles)

Question 26

Name the four functions of neurons

Answer 26

1. Collect info- from internal or external 2. Make decisions- pass along or ignore 3. Transmit Info-product signals 4. Transfer info- tells sweat glands to sweat for example

Question 27

Neurons transmit info by producing signals ____

Answer 27

electrochemically

Question 28

The first Neuron function experiment results showed that

Answer 28

no matter how much voltage or juice, the squid leg will always produce the same action potential maximum

Question 29

In the first experiment, explain the charge within the membrane

Answer 29

starts at negative in resting potential, shoots up to positive charge, then ends in more negative than resting potential value at one point

Question 30

threshold definition

Answer 30

amount of stimulation needed for action potential to occur

Question 31

all or nothing principle

Answer 31

the action potential will always fire at its maximum or nothing at all, regardless of the voltage given

Question 32

resting potential

Answer 32

axon not conduction a nerve impulse

Question 33

when the squid leg was at resting potential the charge was

Answer 33

negative because the sodium ions could not get in and potassium ions could not get out through the blocked plasma membrane

Question 34

action potential

Answer 34

rapid change in axon that causes a nerve impulse

Question 35

the action potential is what caused the

Answer 35

sodium gates to open

Question 36

action potential causes ______.

Answer 36

depolarization- change in electronegativity

Question 37

once the sodium gates opened up

Answer 37

potassium remains, sodium rushes in, more ions within so positive membrane

Question 38

repolarization

Answer 38

opens the potassium gate

Question 39

once the potassium gate is opened

Answer 39

potassium leaves the membrane and sodium remains in the membrane

Question 40

how can the potassium ions leave through the opened gates

Answer 40

by the increased level in positive ions

Question 41

after potassium is released and sodium remains inside,

Answer 41

the gates are both blocked off, and resting potential is restored for the process to be repeated and another neuron can fire

Question 42

hyperpolarization

Answer 42

voltage drops lower and more negative than the voltage reading at resting potential

Question 43

hyperpolarization allows

Answer 43

the potassium and sodium concentrations to build back up on both sides of the membrane

Question 44

the second neuron experiment results shows that

Answer 44

two volt meters were connected, shows that neurons process one signal at a time and at different times

Question 45

what are three ways to generate an action potential without electric stimulation

Answer 45

1. spontaneous generation- randomly opens the gates of potassium and sodium 2. receiving info from firing neuron- most common 3. sensory receptors- what starts it all

Question 46

the function of neurotransmitters

Answer 46

to send the information across the synapse gap

Question 47

neurotransmitters are stored in

Answer 47

the axon terminals

Question 48

two parts to the synapse

Answer 48

presynaptic membrane- sending neuron | postsynaptic membrane- receiving neuron

Question 49

the _____ in the muscles causes action potential

Answer 49

contraction

Question 50

the third neuron functioning experiment showed that

Answer 50

the maximum value of the action potential does not increase, by frequency increases and firing is more rapid

Question 51

the fourth neuron functioning experiment showed that

Answer 51

neurons get fatigued and will stop signaling after a while, this is a good thing

Question 52

sensory adaptation

Answer 52

presence of constant stimulation= less sensitive receptor= excitement rate slows