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bio110 > Chapter 7,8,9 > Flashcards

Chapter 7,8,9 Flashcards

1
Q

Which component of the endocrine system produces the body’s major metabolic hormone? and what two hormones?

A

Thyroid gland (thyroid hormone- stimulates the metabolic rate)
and
(calcitonin- decreases blood calcium levels, stimulates osteoblasts in bone to take Ca+2 from the blood and deposit it in bone matrix) this hormone is antagonistic to parathyroid hormone

found at base of the throat and has 2 lobes and a connecting isthmus
the thyroid hormone

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2
Q

What has four small masses on posterior of the thyroid gland? what hormone does this gland secrete?

A

parathyroid glands
PTH (Parathyroid hormone-increases blood calcium levels, stimulates osteoclasts to release Ca+2 from bone matrix, stimulates kidneys and intestine to absorb more Ca+2) antagonistic to calcitonin
regulates blood calcium levels

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3
Q

what secretes insulin and glucagon to regulate blood glucose levels and where is it located

A

the pancreas- located in abdomen, close to stomach
mixed gland and has both endocrine and exocrine functions

alpha cells release glucagon

beta cells release insulin

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4
Q

What is the size of a pea, protected by the sphenoid bone, connected to hypothalamus by —- stalk? Hormone it releases is controlled by hypothalamus. It has 2 functional lobes

A

anterior pituitary gland- glandular tissue: secretes 6 hormones
posterior pituitary-nervous tissue secretes 2 hormones

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5
Q

How are blood levels of most hormones kept within a narrow range ?

A

negative feedback: which is a homeostatic mechanism. endocrine gland secretes hormone until it receives a feedback signaling the gland to inhibit hormone secretion

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6
Q

what involves nerve fibers directly stimulating hormone release from an endocrine gland?

A

neural stimuli,

most endocrine glands respond to hormonal or humoral stimuli

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7
Q

one of the cell mechanisms hormones act through is
(H-R)hormone receptors binding initiates a series of reactions that result in the activation of enzymes and changes in metabolism.

A

second-messenger system
They are used by protein, peptide, and amine hormones which are water soluble. so must bind to receptor

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8
Q

this results in synthesis of new proteins, used by steroid hormones. they are lipid soluble

A

direct gene activation
all steroids use gene activation

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9
Q

what releases insulin in response to high blood glucose levels?

A

produced by beta cells of pancreatic islets
actions: lowers blood sugar level and stimulate the uptake of sugar by body cells, especially liver, adipose, and skeletal muscle cells

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10
Q

what releases glucagon in response to low blood glucose levels produced in pancreatic islets

A

alpha cells - raises blood sugar level and stimulates the release of stored sugar from liver

glucagon increases blood glucose levels by stimulating the liver to break down stored glycogen into glucose and release that glucose into the blood

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11
Q

the hormone that simulates the contraction of smooth muscle in the uterus is

A

oxytocin, oxytocin also initiates milk ejection during lactation

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12
Q

what triggers ovulation and ovarian production of estrogens and progesterone in women?

A

luteinizing hormone, this stimulates testosterone production in men

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13
Q

what promotes maturation of ovarian follicles and stimulates production of eggs and sperm

A

follicle stimulating hormone, in men it stimulates sperm production

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14
Q

the posterior pituitary stores and releases which hormones?

A

(oxytocin-stimulates uterine contractions)OT
(antidiuretic hormrone, produced by the hypothalamic neurons- stimulates water retention by the kidneys) ADH

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15
Q

what does the anterior pituitary gland produce and release?

A

(prolactin-stimulates milk production)PRL
(growth hormone-stimulates growth, especially in bones and muscles) GH
(Thyroid-stimulated hormone - stimulates thyroid gland to secrete thyroid hormone)TSH
(adrenocorticotropic hormone-stimulates the adrenal cortex to secrete glucocorticoids like cortisol) ACTH
(follicle-stimulating hormone-stimulates the production of sperm and eggs) FSH
(luteinizing hormone-stimulates the testes and ovaries) LH

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16
Q

what hormone produced by the placenta loosens pelvic ligaments prior to birth

A

relaxin

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17
Q

what triggers ovulation of an egg from the ovary and stimulates testosterone production in the testes

A

(luteinizing hormone-stimulates the testes and ovaries) LH

an anterior pituitary hormone

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18
Q

where are the parathyroid glands located

A

posterior surface of the thyroid gland, they release parathyroid hormone in response to low blood calcium ion levels

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19
Q

where is the thymus located and what hormone does it secrete for what?

A

anterior to heart and posterior to the sternum
largest in infants and children
Secretes thymosin-involved with the development of the immune system

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20
Q

ON the the superior surface of each kidney (suprarenal glands)
has 2 regions

A

Adrenal glands
(adrenal cortex-outer 80-90% of gland)
(adrenal medulla- inner 10-20% of gland, nervous tissue

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21
Q

what secretes nonhormonal substances into ducts that empty onto a membrane surface

A

exocrine glands, such as salivary glands and sweat glands

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22
Q

what are the gonadotropic hormones

A

luteinizing hormone and follicle stimulating hormone

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23
Q

what causes acromegaly a condition in which the bones of the face, hands and feet enlarge and widen

A

hypersecretion of growth hormone in an adult
what is it called when there is hyposecretion of growth hormone, gigantism

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24
Q

Has three layers that secrete different steroid hormones in region of adrenal glands

A

adrenal cortex
Mineralocorticoids (mainly aldosterone) stimulates Na+ retention and K+ elimination by the kidneys

glucocorticoids (mainly cortisol) stimulates increase in blood sugar level in response to long-term stress

Sex hormones- low levels of androgens and estrogens

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25
Q

which hormone from the adrenal cortex targets the kidney tubules by stimulating the retention of sodium ions and secretion of potassium ions into the urine?

A

aldosterone

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26
Q

where is thyroid gland located

A

in the anterior neck just inferior to the voice box

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27
Q

a hormone that works by direct gene activation must be

A

lipid soluble

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28
Q

which hormone is the most important regulator of blood calcium ion levels

A

parathyroid hormone

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29
Q

a current that is continuously regenerated along the length of the axon and does not die out

A

action potential

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30
Q

the part of the PNS that sends sensory input to the CNS from sensory receptors around the body

A

afferent (sensory division)
Sensory (afferent) neurons
Structure: most unipolar; some bipolar
Cell bodies in ganglia
Carry impulses from the sensory receptors to
the CNS

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31
Q

the middle layer of the meninges, had weblike extensions attach to the inner layer, the pia mater

A

arachnoid mater

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32
Q

nervous tissue support cells
abundant, start shaped cells
form barrier btwn capillaries and neurons
control the chemical environment of the brain

A

astrocytes

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33
Q

what is a stimulus

A

a change in the environment

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34
Q

what is the master controlling and communicating system of the body
fasting acting, skeletal muscles contract;; exocrine glands secrete

A

nervous system: it uses nerve impulses and neurotransmitters

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35
Q

what are the functions of the nervous system

A

3 overlapping functions

Sensory input
To monitor changes (stimuli) occurring
inside and outside the body
Gather information

Integration
Process and interpret sensory input
Decide if action is needed

Motor output
Response to integrated stimuli
Activates muscles or glands

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36
Q

what gathers information and monitors changes, stimuli occuring inside and outside the body

A

sensory input

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37
Q

what is the process and interpret sensory input and decide if action is needed

A

integration

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38
Q

what response to integrated stimuli and activate muscles to contract or glands secrete

A

motor output

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39
Q

PNSperipheral nervous system

A

Nerves and ganglia
Nerve = bundle of neuron fibers (axons)
Cranial nerves arise from brain
12 pairs
Vagus (CN X) – main parasympathetic nerve
Spinal nerves arise from spinal cord
31 pairs of mixed nerves
Carry both sensory and motor fibers
Ganglion – cluster of neuronal cell bodies in PNS

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40
Q

what is the region that initiates action potential (impulses)

A

trigger zone

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41
Q

what is a neurons ability to respond to stimuli and convert it into an action potential (nerve impulse)

A

irritability

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42
Q

what is a neurons ability to transmit an impulse and send signal to next cell

A

conductivity

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43
Q

what part of nervous system monitors changes (stimuli) occurring in side and outside the body

gathers information

A

sensory input (on afferent pathway)

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44
Q

what part of nervous system responds to integrated stimuli

and activates muscle or glands

A

motor output to an effector like skeletal muscle

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45
Q

what is the structural classification of nervous system

A

Structural Classification

Central Nervous System
(CNS)
Brain and Spinal Cord

Peripheral Nervous System
(PNS)
Nerves outside the
brain and spinal cord
Cranial and spinal
nerves

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46
Q

what is central nervous system composed of

A

brain and spinal cord

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47
Q

what is the peripheral nervous system composed of

A

cranial nerves and spinal nerves

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48
Q

in the sensory division
what carries information from peripheral Nervous system to the central nervous system

A

nerve fibers

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49
Q

what are the two subdivisions of the motor division (efferent)

A

somatic nervous system: voluntary, skeletal muscle

autonomic nervous system
involuntary, smooth muscle cardiac muscle glands

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50
Q

what are the effectors of the autonomic nervous system?

A

smooth muscle, cardiac muscle, and glands

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51
Q

what does nervous system consists of

A

neurons and neuroglia
(6types of glial cells)
oligodendrocytes
schwann cells
ependymal cells
astrocytes
microglia
satellite cells

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52
Q

what are structural and functional differences between neurons and neuroglia

A

neurons are the structural and functional unit of the nervous system and conduct nerve impulse

neuroglia are support cells that provide physical support insulation and nutrients to neurons

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53
Q

what is another name for nerve impulses?

A

action potentials

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54
Q

what is most abundant glial cell? star shaped cells
touch capillaries and neuron

A

astrocytes

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55
Q

what does blood brain barrior do by the astrocytes

A

forms a barrier btwn capillaries and neurons and controls the chemical environment of the brain

Includes the least permeable capillaries of the
body
Excludes many potentially harmful substances
Useless as a barrier against some substances
Fats and fat soluble molecules
Respiratory gases (CO2 and O2)
Alcohol
Nicotine
Anesthesia

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56
Q

nervous tissue support cells
phagocytose bacterial cells and cellular debris in the CNS

A

microglia

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57
Q

what lines the cavities of the brain and the central canal of the spinal cord and circulate cerebrospinal fluid

A

ependymal cells

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58
Q

what wraps around nerve fibers (axons) in the CNS and produce myelin sheaths made of nervous tissue support cells

A

oligodendrocytes

In CNS, oligodendrocytes
form the myelin sheath
No neurilemma

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59
Q

nervous tissue support cells that protect neuron cell bodies in ganglia of the peripheral nervous system

A

satellite cells

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60
Q

other glial cell found in PNS that form myelin sheath around axons in the peripheral nervous system like a jelly roll fashion

A

schwann cells

Axons are either myelinated or
unmyleinated

Unmyelinated axon
Schwann cell surrounds
region of several axons

Myelinated axons
In PNS, Schwann cells wrap
around peripheral axons in
jelly-roll fashion

Layers of cell membrane
create myelin sheath
Whitish, fatty material

Neurilemma
Portion of Schwann cell
that contains most of the
cytoplasm and nucleus

n CNS, oligodendrocytes
form the myelin sheath
No neurilemma

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61
Q

cells specialized to transmit nerve impulses or action potential. the 3 major regions of have a cell body, dendrites, axon

A

neurons=nerve cells

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62
Q

what is another name for cell body

A

soma

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63
Q

anatomy of cell body

A

nucleus
large nucleolus
nissl substance
neurofibrils

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64
Q

what is the specialized rough endoplasmic reticulum of the cell body

A

nissl substance

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65
Q

what helps maintain cell shape of cell body

A

neurofibrils

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66
Q

what is short highly branched cytoplasmic extensions that conduct signoals toward the cell body

A

dendrites

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67
Q

what only has one neuron, arises from the axon hillock and may have branches, collaterals
and a
trigger zone

A

axon

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68
Q

what contains vesicles with neurotransmitters

A

axon terminals

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69
Q

what is gap separated from one neuron to next

A

synaptic cleft, gap btwn adjacent neurons

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70
Q

transmission of a signal at synapses

A

Impulses are not directly able to cross the synapse to
another neuron
1. Action potential causes synaptic vesicle to move
to membrane
2. Neurotransmitter is released from axon terminal
3. Neurotransmitter diffuses across synaptic cleft
4. Neurotransmitter binds to receptor channel on
the dendrite or soma of the postsynaptic neuron
5. Receptor channel opens
6. Na+ entering postsynaptic neuron helps neuron
reach threshold and generate an action potential

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71
Q

How does nervous system function? the process?

A

Functional Classification

Sensory (afferent) division
Nerve fibers that carry
information to the central
nervous system

Motor (efferent) division
Nerve fibers that carry
impulses away from the
central nervous system

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72
Q

what are the two control systems in the body

A

nervous system and endocrine system

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73
Q

slow acting control system could take minutes to hours to days as well as turning off; controls metabolism of virtually all cells; uses hormones (chemical messenger)

A

endocrine system

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74
Q

what are some major hormonal actions

A

regulation of metabolism
maintenance of homeostasis
mobilzation of body defenses
growth and development
reproduction

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75
Q

what are ductless glands;
produce hormones and secrete hormones into the blood, and have a rich blood supply, formed from epithelial tissue

A

endocrine glands

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76
Q

what only has cells with the appropriate receptors are affected by a specific hormone;

H-R (Hormone receptor binding initiates a cellular response

Blood transports hormones to these

A

target cells: it has a receptor for a specific hormone

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77
Q

what are the 3 groups of chemical classification of the chemistry of hormones

A

amino acids-proteins; peptides; amines (structure based on amino acids)

steroids-made from cholesterol

prostaglandins-made from lipids (secreted by virtually body cells) classified as local hormones meaning the target cells are neighboring cells. ex: inflammation, fever, blood clotting, gastric secretions

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78
Q

what are hormones made from proteins, peptides, amines

A

amino acids

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79
Q

what are the hormones made from cholesterol

A

steroids

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80
Q

what are the hormones made from lipids secreted by virtually all body cells;

A

prostaglandins

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81
Q

what are the mechanisms of hormones action. what activates genes so proteins are synthesized?

A

steroid hormones

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82
Q

What is irritability

A

The ability to respond to stimuli and convert it into an action potential

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83
Q

What is conductivity

A

Ability to transmit an impulse and send signal to next cell

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84
Q

Membrane potential

A

Means voltage.
It is a difference in charge btwn the extracellular fluid and the intercellular fluid

Potential difference across cell membrane
Plasma membrane is polarized at rest
Fewer positive ions are inside the cell than
outside the cell
Resting membrane potential (RMP) varies with
cell type
-40 to -90 mV

Membrane potential is due to
Distribution of ions across plasma membrane
[Na+] high outside cell; low inside
[K+] low outside cell; high inside
Negatively charge molecules
DNA, RNA, proteins
Membrane permeability to Na+ and K+
Na+/K+ pump (3Na+ out: 2K+ in)

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85
Q

At resting what is membrane considered

A

Polarized membrane potential

Outside is positive and inside negative because fewer positive ions are inside the cell than outside the cell

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86
Q

Resting membrane potential

A

The voltage difference at resting varies with cell type
-40 to -90 mV

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87
Q

Resting Membrane potential for sodium and potassium is due to

A

Distribution of ions across plasma membrane

Na+ high outside cell; low inside

K+ low outside cell; high inside

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88
Q

DNA, RBA, proteins contribute to resting membrane potential because

A

Negatively charged molecules

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89
Q

What contributes to membrane potential in resting neuron

A
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90
Q

What is depolarization and repolarization

A

Membrane Potential Changes

Depolarization
Membrane potential becomes less
negative (more positive)
Na+ channels open; K+ channels closed
Na+ enters cell sodium defuses into the cell
sodium enters the cell

at peak of action potential the sodium channels close

Repolarization
Membrane potential returns to RMP
K+ channels open; Na+ channels closed
K+ leaves cell

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91
Q

What is repolarization

A

when membrane potential returns to resting membrane potential or RMP

what happens is k+ potassium channels open, and Na+ sodium channels are closed

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92
Q

What is an action potential

A

Rapid sequence of depolarization and repolarization

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93
Q

Resting potential of a neuron

A

-70

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94
Q

Threshold potential

A

Membrane potential at which an action potential is generated

Stimuli from other neurons sum to bring membrane to threshold

For a neuron threshold potential is
-55mV

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95
Q

What is the peak voltage of action potential for a neuron

A

+10mV

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96
Q

Where is action potential will be initiated at

A

The trigger zone of an axon

If the action potential is generated it is propagated over the entire action

Begins at trigger zone to end at axon terminals

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97
Q

how are action potentials conducted down the axon

A

depends whether it is myelinated or unmyelinated

On myelinated axons
Action potentials occur only at nodes of
Ranvier
Saltatory conduction: AP appears to jump
from node to node
Relatively fast: 120 m/sec

On unmyelinated axon
Action potential travels along entire
plasma membrane
Relatively slow: 0.5 m/sec

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98
Q

AP appears to jump from node of ranvier to node of ranvier

A

saltatory conduction, relatively fast 120m/sec on myelinated axon

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99
Q

What is the membrane potential at which the action potential is generated

A

an action potential is generated when a stimulus changes the membrane potential to the values of threshold potential. The threshold potential is usually around -50 to -55 mV.

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100
Q

conduction on unmyelinated axon

A

action potential travels along entire plasma membrane

relatively slow .5m/sec slow for action potential

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101
Q

neurons not in direct physical contact with cell that it stimulate or innervates
the fluid filled space btwn axon terminal and membrane

A

synaptic cleft is the name of the gap

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102
Q

post synaptic neuron transmits to?

A

can be dendrites or cell body, covered with synapses

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103
Q

what is junction btwn 2 neurons

A

synapse

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104
Q

transmission of the signal at synapses steps or events at a synapse

A

impulses are not directly able to cross the synapse to another neuron, transmission involves neurotransmitter

  1. AP causes synaptic vesicle to move membrane
    2.neurotransmitter is released from axon terminal
    3.neurotransmitter diffuses across synaptic cleft
    4.neurotransmitter binds to receptor channel on the dendrite or soma of the postsynaptic neuron
    5.receptor channel opens
    6.Na+ entering the post synaptic neuron reaching threshold and generated an action potential

To stop signal:
1. Presynaptic neuron stops releasing
neurotransmitter
2. Neurotransmitter diffuses away from cleft, is
broken down, or is taken up into axon terminal

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105
Q

how do we stop a signal of transmission of signal at synapses

A

1.presynaptic neuron stops releasing neurotransmitter
2.neurotransmiter diffuses away from cleft, is broken down, or is taken up into axon terminal and recycled

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106
Q

where are neurotransmitters stored

A

within synaptic vesicles

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107
Q

what is a physiology reflexes

A

Rapid, predictable and involuntary response to stimuli

Somatic reflexes
Reflexes that stimulate the skeletal muscles

Example: pulling your hand away from a hot object

Autonomic reflexes
Regulate the activity of smooth muscles, the heart,
and glands
Example: regulation of smooth muscles, heart and
blood pressure, glands, digestive system

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108
Q

refexes that stimulate the skeletal muscles, example pulling hand away from hot object

A

somatic reflexes

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109
Q

regulate the activity of smooth muscles, the heart, and glands. ex ample:regulation of smooth muscles, heart and blood pressure, glands, digestive system

A

autonomic reflexes

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110
Q

components of a typical reflex arc

Example: flexor (withdrawal) reflex called three neuron reflex arc

Two-neuron reflex arcs
Simplest type
Example: patellar (knee-jerk) reflex

A

five elements of a reflex
1. sensory receptor-reacts to a stimulus
2.sensory neuron-carries message to the integration center
3.integration center-(CNS; interneuron) processes information and directs motor output
4. motor neuron-carries message to an effector (form of AP)
5. effector organ- is the muscle or gland to be stimulated

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111
Q

what happens in a three-neuron reflex arc
or identify the elements of a reflex in the correct order

A

consists of five elements
1. receptor
2.sensory neuron
3.interneuron
4.motor neuron
5.effector

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112
Q

what are the layers that protect the central nervous system

A

1st layer-scalp and skin
skull and vertebral column
meninges
cerebrospinal fluid (CSF)
blood-brain barrier

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113
Q

what are the meninges layers, 3 connective tissue membranes covering and protecting brain and spinal cord

A

dura mater-very tough
arachnoid mater
pia mater-on surface on brain and spinal cord

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114
Q

what is the fluid surrounding brain and spinal cord

A

cerebrospinal fluid (CSF)

Similar to blood plasma composition
Formed by the choroid plexus; resorbed by
arachnoid villi
Forms a watery cushion to protect the brain
Circulated in subarachnoid space, ventricles, and
central canal of the spinal cord

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115
Q

double-layered external covering
separates to form dural sinuses filled with venus blood

A

dura mater

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116
Q

middle layer
web-like

A

arachnoid mater

117
Q

clings to surface of brain and spinal cord
contain superficial blood vessels

A

pia mater

118
Q

space between arachnoid and pia mater filled with cerebrospinal fluid

A

subarachnoid space

119
Q

what covers brain and spinal cord?

A

meninges

Dura mater
Double-layered external covering
Separates to form dural sinuses
Arachnoid layer
Middle layer
Web-like
Pia mater
Clings to surface of brain and spinal cord
Contain superficial blood vessels

Subarachnoid space
Space between arachnoid and pia mater
Filled with cerebrospinal fluid

120
Q

how many layers is the dura mater in the spinal cord

A

1

121
Q

what is space between meninges surrounding spinal cord and bones of the vertebral canal, filled with adipose tissue and loose connective tissue

A

epidural space
space surround the dura mater

122
Q

similar to blood plasma composition
formed by the choroid plexus
resorbed by arachnoid villi
forms a watery cushion to protect the brain

A

cerebrospinal fluid(CSF)
formed within the ventricles
circulated in subarachnoid space

123
Q

4 interconnected cavities within brain filled with CSF

A

ventricles
(2lateral, 3rd and 4th ventricles)

Ventricles
4 interconnected cavities within brain filled
with CSF (2 lateral, 3rd and 4th ventricles)

124
Q

what structure makes cerebrospinal fluid

A

choroid plexus

125
Q

includes the least permeable capillaries of the body
excludes many potentially harmful substances
useless as a barrier against some substances

A

blood-brain barrier

126
Q

what are some useless as a barrier against some substances

A

fats and fat soluble molecules
respiratory gases (co2 & o2)
alcohol
nicotine
anesthesia

127
Q

what are the 4 major portions for the brain

A

4 major portions
Cerebrum (cerebral hemispheres),
diencephalon, brain stem, cerebellum

128
Q

includes more than half of the brain mass
Three main regions of cerebrum
Gray matter — outer layer in the cerebral
cortex composed mostly of neuron cell bodies
White matter —composed of myelinated axons
Basal nuclei — regions of gray matter buried
within the white matter

A

cerebrum

129
Q

outer layer in the cerebral cortex composed mostly of neuron cell bodies in the cerebrum
and unmyelinated fibers

A

gray matter

Internal gray matter is mostly cell bodies
Dorsal (posterior) horns
Anterior (ventral) horns
Gray commissure surrounds the central canal
Central canal is filled with CSF

130
Q

composed of myelinated axons in the cerebrum

A

white matter

Exterior white mater — fiber tracts
Ascending tracts
Carry sensory information to brain
Descending tracts
Conduct motor impulses from brain to
motor neurons

131
Q

regions of gray matter buried within the white matter of cerebrum

A

basal nuclei

132
Q

what is the thin layer of gray matter on the surface of the brain called

A

cerebral cortex

133
Q

midsaggital line the longitudinal fissure divides the cerebrum into 2 hemispheres

A

Cerebrum divided into 2 hemispheres
Paired (left and right) superior parts of the
brain
Connected internally by corpus callosum
Surface is made of ridges (gyri) and grooves
(sulci)

134
Q

in the cerebrum what is an area that is the Primary motor area
Voluntary control of skeletal muscles
Sends impulses to skeletal muscles
Broca’s area - “motor speech”
Involved in our ability to speak
Problem solving; working memory; judgment
Language comprehension region

A

primary motor area in the frontal lobe

135
Q

in the cerebrum what is an area that is involved in our ability to speak

A

broca’s area-motor speech also in the frontal lobe

136
Q

vision area in the cerebrum, everything involved with vision

A

occipital lobe

137
Q

in the cerebrum the fiber tracts-bundles of myelinated axons, deep to grey matter

A

white matter

138
Q

what are bundles of myelinated axons

A

fiber tracts

139
Q

what is the largest fiber tract that connects hemispheres of the cerebrum

A

corpus callosum

140
Q

regulate skeletal muscle movements (starting and stopping activity

A

basal nuclei

141
Q

what sits on top of the brain stem, enclosed by the cerebral hemispheres, main parts thalamus and hypothalamus
deep to 2 cerebral hemispheres

A

diencephalon

142
Q

the relay station for sensory impulses;

transfers impulses to the correct part of the cortex for localization and interpretation

what surrounds the third ventricle;

A

thalamus

143
Q

where is hypothalamus located in the body and what does it do?

A

below the thalamus,

important autonomic nervous system center;

helps regulate body temp, controls water balance,

regulates metabolism;

important part of the limbic system (emotions);

regulates secretions of hormones from pituitary gland

144
Q

which part of the brain is a relay station for sensory information

A

thalamus
Surrounds the third
ventricle
The relay station for
sensory impulses
Transfers impulses to
the correct part of the
cortex for localization
and interpretation

145
Q

what attaches to the spinal cord, and has midbrain, pons, medulla oblongata

A

parts of brain stem

146
Q

mostly composed of tracts of nerve fibers;
reflex centers for vision and hearing in the brain stem

A

midbrain

147
Q

mostly fiber tracts;
modifies activity of respiratory centers in the medulla

A

pons

148
Q

what important control centers that control heart rate ; blood pressure regulation ;breathing (respiratory center-set basic rate and depth of breathing); swallowing and vomiting

A

medulla oblongata
the lowest part of the brain stem;
merges into spinal cord (has tracts); contains important control centers

149
Q

coordinates skeletal muscle activity; helps maintain posture; balance and equilibrium

A

cerebellum

150
Q

Slender column of nerve fibers (tracts) and neurons
Center for spinal reflexes
Surface anatomy
Occipital bone to the 1st or 2nd lumbar vertebra
(L1-L2)
31 pairs of spinal nerves
Cauda equina is a collection of spinal roots at the
inferior end
Anterior median fissure
Posterior median sulcus

A

spinal cord

151
Q

how many pairs of spinal nerves are there in the spinal cord

A

31pairs

152
Q

what is a collection of spinal roots or cluster of nerve roots at the inferior end of the spinal cord

A

cauda equina

153
Q

a deep groove; on the front surface of spine; anterior on the midline

A

anterior median fissure

154
Q

shallow groove on the midline on the posterior spinal cord

A

posterior median sulcus

155
Q

at what vertebral level does the spinal cord end

A

L1

156
Q

which type of matter is on the exterior of spinal cord

A

exterior white matter

157
Q

sensory fibers; cell bodies of these neurons found in the dorsal root ganglia

A

dorsal (posterior) roots

158
Q

contains motor fibers; cell bodies of these motor neurons are found in the anterior horn

A

ventral (anterior) roots

159
Q

what type of fiber is located in the posterior roots

A

sensory fibers

160
Q

what conducts signal away from cell body toward axon terminal

A

axon

161
Q

when membrane potential becomes more positive or less negative

A

depolarization

162
Q

what is the end of axon called

A

axon terminal

163
Q

what is the specialized RER found in a neuron

A

nissl substance

164
Q

what are the phagocytic cells found in CNS called

A

microglia

165
Q

what produce myelin sheath in CNS

A

oligodendrocytes

166
Q

brain and spinal cord

A

central nervous system

167
Q

form myelin sheath in PNS

A

schwann cells

168
Q

conduction of an action potential in a myelinated axon

A

saltatory conduction

169
Q

rapid, involuntary, predictable response to stimulus

A

reflex

170
Q

nerous tissue support cells
line cavities of the brain and spinal cord
circulate cerebrospinal fluid
(glial cells that help circulate CSF)

A

ependymal cells

171
Q

protein on postsynaptic membrane that binds neurotransmitter

A

neurotransmitter receptor

172
Q

when membrane potential returns to resting values

A

repolarization

173
Q

part of a neuron that sends incoming signals toward cell body

A

dendrites

174
Q

structure of most common sensory neuron

A

unipolar

175
Q

found completely with the CNS connecting neurons together

A

interneurons

176
Q

glial cells that control chemical environment of the brain

A

astrocytes

177
Q

ion that enters cell causing depolarization

A

sodium ion

178
Q

junction between 2 neurons

A

synapse

179
Q

region of any axon where an action potential is initiated

A

trigger zone

180
Q

gaps in the myelin sheath along axon

A

nodes of ranvier

181
Q

what is the membrane potential at which an action potential is generated

A

threshhold potential

Threshold potential
Membrane potential at which an action
potential is generated
Stimuli from other neurons sum to bring
membrane to threshold

182
Q

neuron with many extensions from cell body

A

multipolar neuron

183
Q

collection of neuronal cell bodies located within the PNS

A

ganglion

184
Q

part of the ANS that takes care of housekeeping activities

A

parasympathetic nervous system

185
Q

contains vital centers for breathing, heart rate and blood pressure

A

medulla oblongata

The lowest part of the brain stem
Merges into the spinal cord (has tracts)
Contains important control centers
Heart rate control
Blood pressure regulation
Breathing (respiratory centers – set basic
rate and depth of breathing)
Swallowing & Vomiting

186
Q

location of cell bodies of motor neurons that innervate skeletal muscle

A

anterior horn

187
Q

connective tissue that surrounds a nerve

A

epineurium

188
Q

collection of nerve roots that hangs from the inferior spinal cord

A

cauda equina

189
Q

coordinates skeletal muscle activity; balance and coordination

A

cerebellum

190
Q

bundle of axons found in the CNS

A

tract

191
Q

type of fiber located in anterior roots

A

motor fiber

192
Q

space between arachnoid and pia mater

A

subarachnoid space

193
Q

formed when posterior and anterior roots merge

A

spinal nerve

194
Q

region of the brain that interprets most body sensations

A

parietal lobe

Primary somatic sensory area
Receives and interprets impulses from the
body’s sensory receptors
Speech/language region

195
Q

helps regulate body temperature and water balance

A

hypothalamus
Under the thalamus
**important autonomic
nervous system center
**Helps regulate body
temperature
**Controls water
balance
**Regulates
metabolism
**Important part of the
limbic system (emotions)
** Regulates secretions of
hormones from pituitary
gland

196
Q

type of fiber located within the posterior roots

A

sensory fiber

197
Q

part of the ANS used in emergencies and during exercise

A

sympathetic nervous system

198
Q

tracts that carry sensory information to brain

A

ascending tracts

199
Q

bundle of axons found in the peripheral nervous system

A

nerves
Neuron fibers are bundled by
connective tissue
* Endoneurium surrounds
each fiber
* Groups of fibers are bound
into fascicles by perineurium
* Fascicles are bound together
by epineurium

200
Q

Label images

A

Dendrites
Axon hillock
Cell body/soma
Nucleus
Schwann cells
Node of ranvier
Axon terminals

201
Q
A

Nucleus

202
Q
A

Cell body

203
Q
A

Axon hillock

204
Q
A

Schwann cell

205
Q
A

Axon terminal

206
Q
A

Pia mater

207
Q
A

Longitudinal fissure

208
Q
A

Longitudinal fissure

209
Q
A

Cerebral cortex

210
Q
A

Transverse fissure

211
Q
A

Lateral ventricle

212
Q
A

Lateral ventricle

213
Q
A

Third ventricle

214
Q
A

Fourth ventricle

215
Q

what does this do?

A

Frontal lobe, primary motor area
voluntary control of skeletal muscles
sends impulses to skeletal muscles

Broca’s area- motor speech
involved in our ability to speak

problem solving; working memory; judgment

language comprehension region

216
Q

what does this do?

A

Parietal lobe, primary somatic sensory area.
receives and interprets impulses from the body’s sensory receptors

speech/language region

217
Q

what does this do?

A

Temporal lobe, olfaction (smell), hearing

218
Q

what is a cluster of neuronal cell bodies (somas) located in the peripheral nervous system called

A

ganglion

219
Q

Which connective tissue bundles axons into fascicles

A

Perineurium

220
Q

what is a sensation of pain from visceral organs that appears to arise from skin

A

referred pain

Cutaneous and visceral sensory neurons
conduct nerve impulses through same
ascending tracts

Visceral injury usually results in dull pain
that is hard to localize
* Clinicians know that pain felt in certain
somatic regions could be referred from the
viscera

221
Q

what are the two subdivisions of the autonomic nervous system

A

Sympathetic nervous system (SNS)
Extraordinary situations (fight or flight)
Exercise, excitement, emergency and
embarrassment

Parasympathetic nervous system (PSNS)
Housekeeping activities (rest and repose)
Digestion, defecation, and diuresis

222
Q

the system the involve extraordinary situations, exercise, excitement, emergency, and embarra

A

sympathetic nervous system

223
Q

system that involves the normal housekeeping activities, digestion, defecation, and diuresis

A

parasympathetic nervous system

224
Q

digestive system-effects of sympathetic and parasympathetic divisions of the autonomic nervous system

A

PSNS: increases smooth muscle mobility and amount of secretion by glands and relaxes sphincters

SNS: decreases activity and constricts sphincters

225
Q

lungs-effects of sympathetic and parasympathetic divisions of the autonomic nervous system

A

PSNS: constricts bronchioles

SNS: dilates bronchioles

226
Q

heart-effects of sympathetic and parasympathetic divisions of the autonomic nervous system

A

PSNS: decreases rate; slows and steadies

SNS: increases rate and force

227
Q

blood vessels-effects of sympathetic and parasympathetic divisions of the autonomic nervous system

A

PSNS: no effect on most blood vessels

SNS: constricts blood vessels in viscera and skin; increases blood pressure

228
Q

glands-salivary, lacrimal, gastric-effects of sympathetic and parasympathetic divisions of the autonomic nervous system

A

PSNS: stimulates increases production of saliva, tears,

SNS: inhibits; result is dry mouth and dry eyes

229
Q

eye-effects of sympathetic and parasympathetic divisions of the autonomic nervous system

A

PSNS stimulates constrictor muscles; constricts pupils

SNS: stimulates dilator muscles; dilates pupils

230
Q

sweat glands of skin-effects of sympathetic and parasympathetic divisions of the autonomic nervous system

A

PSNS: no effect

SNS; stimulates to produce perspiration

231
Q

arrector pili muscles attached to hair follicles

A

PSNS; no effect

SNS; stimulates; produces good bumps

232
Q

what is humoral stimulation

A

refers to the control of hormone release in response to changes in extracellular fluids such as blood or the ion concentration in the blood

ions or nutrients cause the release of hormones

233
Q

what secretes epinephrine the flight or flight hormone

A

adrenal medulla
stimulates increases in blood sugar
increases blood flow to skeletal muscles
increases metabolic rate in response to short term stress

234
Q

what simulates milk production

A

(prolactin-stimulates milk production)PRL
affect non-endocrine targets

235
Q

what produces sperm, secretes androgens, testosterone

A

testes, gonads

236
Q

a hormone secreted by the thyroid that has the effect of lowering blood calcium.

A

calcitonin

237
Q

chemical messenger of the endocrine system uses, what actions do they accomplish

A

hormone

regulation of metabolism
maintenance of homeostasis
mobilization of body defenses
reproduction

238
Q

endocrine gland secretes hormone until ?

A

it receives feedback signaling the gland to inhibit hormone secretion.

it uses a negative feedback loop that is a homeostatic mechanism

239
Q

what stimuli that activate endocrine glands: 3 kinds and how do they work

A

hormonal stimulation-most common stimulus. endocrine organs are activated by other hormones

humoral stimulation -changing blood levels of certain ions and nutrients stimulate hormone release examples: calcium (parathyroid hormone & calcitonin) or glucose (insulin & glucagon)

neural- stimulate the nerve and impulses stimulate hormone release
ex: release of epinephrine (& some norepinephrine) by the adrenal medulla

240
Q

humoral stimulation

A

changing blood levels of certain ions and nutrients stimulate hormone release

ex: calcium parathyroid hormone

241
Q

what is it called when there is hyposecretion of parathyroid hormone

A

tetany

hyposecretion of parathyroid hormone (PTH). Insufficient PTH leads to reduced blood calcium ion levels, which in turn cause overactivity in neurons that control muscles. Tetany refers to the resulting uncontrollable muscle spasms.

242
Q

affect non-endocrine targets that stimulates growth, especially in bones and muscles

A

growth hormone

243
Q

what is it called when there is hyposecretion of antidiuretic hormone

A

diabetes insipidus

hyposecretion of antidiuretic hormone (ADH). Without ADH, the kidney tubules are unable to reabsorb enough water, leading to excess urine production and continual thirst.

244
Q

what is it called when there is hyposecretion of insulin

A

diabetes mellitus

hyposecretion of insulin. Without adequate insulin production from the pancreas, blood glucose levels rise dramatically. Affected individuals experience excessive urine production and thirst as well as hunger and weight loss.

245
Q

what is it called when there is hypersecretion of thyroid hormone

A

graves’ disease

hypersecretion of thyroid hormone (TH). Graves’ disease is a form of hyperthyroidism in which overproduction of TH causes increased metabolic rate, hyperactivity, weight loss, and a bulging of the eyes anteriorly.

246
Q

Hormones act through what two different cell mechanisms

A

direct gene activation or second-messenger systems

247
Q

Hormones that stimulate other endocrine glands to release hormones

A

tropic hormones
(Thyroid-stimulated hormone - stimulates thyroid gland to secrete thyroid hormone)TSH
(adrenocorticotropic hormone-stimulates the adrenal cortex to secrete glucocorticoids like cortisol) ACTH
(follicle-stimulating hormone-stimulates the production of sperm and eggs) FSH
(luteinizing hormone-stimulates the testes and ovaries) LH

248
Q

Located posterior to the third ventricle of the brain around midbrain. secretes melatonin which is
involved in biological rhythms

A

pineal gland

249
Q

Gonads

A

Ovaries: produce ova, secretes steroid hormones
estrogens-stimulate development and maintenance of female secondary sex characteristics
progesterone-promotes growth uterine lining (endometrium)

Testes: produce sperm and secrete androgens
testosterone- stimulates development and maintenance of male secondary sex characteristics
supports formation of sperm cells

250
Q

Eye

A

70 % of all sensory receptors
1million nerve fibers (axons)
most of the eye is enclosed in a bony orbit
cushion of fat surrounds most of the eye

251
Q

membrane that lines eyelids and covers the outer surface of eye
secretes mucus to lubricate eye and keep it most

A

conjunctiva-membrane that lines the eyelids
includes blood vessels

252
Q

lacrimal gland and ducts

functions: protects, moistens, and lubricates the eye
empties into nasal cavity
secretions contain: dilute salt solution, mucus, antibodies, lysozyme-destroys bacteria

A

lacrimal apparatus
Lacrimal gland-produces lacrimal fluid tears, situated on lateral aspect of each eye

lacrimal canaliculi-drain lacrimal fluid from eyes medially

lacrimal sac-provides passage of lacrimal fluid towards nasal cavity

nasolacrimal duct-empties lacrimal fluid into the nasal cavity

253
Q

six skeletal muscles produce eye movements
originate on wall of orbit and insert into outer surface of eye

A

external eye muscles

254
Q

fluids that fill the interior of eyeball

A

humors

255
Q

smooth muscle; connected to lens by suspensory ligments

A

ciliary body

256
Q

regulates amount of light entering eye, pigmented layer that give eye color

A

iris
pupil rounded opening in the iris

257
Q

wall of eyeball consists of 3 layers

A

outside fibrous layer
sclera -white of the eye, connective tissue layer
cornea- transparent, central anterior portion, allows light to pass through, repairs itself easily, only human tissue that can be transplanted without fear of rejection

choroid- middle , vascular layer-blood rich nutritive layer in the posterior of eye, pigment prevents light from scattering

retina-inside , sensory layer contains 2 layers
outer pigmented layer absorbs light and prevents it from scattering

  inner neural layer that contains receptor cells (photoreceptors) rods & cones
258
Q

What are Photoreceptors that absorb light and send signal to
bipolar neurons then ganglion cells?
* Signals leave retina through the optic nerve
* Optic disc (blind spot) is where the optic nerve
leaves the eyeball
* No photoreceptor cells are at the optic disc, or
blind spot
* Cannot see images focused on the optic disc

A

Photoreceptor cells
* Rods
* Most are found toward the edges of the retina
* Allow vision in dim light and peripheral vision
* All perception is in gray tones

Photoreceptor cells
* Cones
* Allow for detailed color vision
* Densest in the center of the retina
* Fovea centralis – lateral to blind spot
* Area of the retina with only cones
* Region of sharpest vision (visual acuity

259
Q

Cone sensitivity

A

Three types of cones
* Red
* Green
* Blue
* Different cones are sensitive
to different wavelengths
* Color blindness is the result
of the lack of one cone type

260
Q

Biconvex crystal-like structure
* Focuses image on retina
* Held in place by ciliary zonule (suspensory
ligament) attached to the ciliary body

A

lens

Lens divides the eye into two chambers
1. Anterior segment
* Anterior to the lens
* Contains aqueous humor
* Helps maintain intraocular pressure
* Provides nutrients for the lens and cornea

  1. Posterior segment
    * Posterior to the lens
    * Contains vitreous humor
    * Gel-like substance posterior to the lens
    * Prevents the eye from collapsing
    * Helps maintain intraocular pressure
261
Q

physiology of vision

A

Light must be focused to a point on the retina
for optimal vision
* Light is bent, or refracted, by the cornea,
aqueous humor, lens, and vitreous humor
* The eye is set for distance vision (>20ft away)
* Accommodation — the lens must change shape
to focus on closer objects (< 20ft away)

262
Q

Image formed on the retina is a real image
* Real images are:
* Reversed from left to right
* Upside down
* Smaller than the object

A

The pathway of light
through the eye:
1. Cornea
2. Aqueous humor
3. Through pupil
4. Aqueous humor
5. Lens
6. Vitreous humor
7. Retina

263
Q

Location where the optic nerves cross
* Fibers from the medial side of each eye cross
over to the opposite side of the brain

A

optic chiasma

264
Q

Contain fibers from the lateral side of the eye
on the same side and the medial side of the
opposite eye

A

optic tracts

265
Q

The pathway of nerve impulses from the
retina of the eye into the brain:

A
  1. Optic nerve
  2. Optic chiasm
  3. Optic tract
  4. Thalamus
  5. Optic radiation
  6. Visual cortex in occipital lobe of brain
266
Q

visual fields

A

Visual field – what an eye “sees”
* Slightly different visual field for each eye
* Visual fields overlap
* Inputs from both eyes to each optic cortex
provide for depth perception

267
Q

the ear is divided into three areas

A

External (outer) ear
2. Middle ear (tympanic cavity)
3. Inner ear (bony labyrinth

268
Q

Involved in hearing only
* Structures of the external ear
* Auricle (pinna)
* External acoustic meatus
(auditory canal)
* In the temporal bone
* Lined with skin and
ceruminous glands
* Ends at the tympanic
membrane (eardrum)

A

external ear tympanic cavity

269
Q

Air-filled cavity within the
temporal bone
* Involved only in the sense
of hearing
* Located between tympanic
membrane and oval and
round windows

A

middle ear tympanic cavity

270
Q

Includes sense organs for
hearing and balance
* Maze of bony chambers within
the temporal bone that forms
the:
* Cochlea
* Vestibule
* Semicircular canals

A

inner ear and bony labyrinth
Membranous labyrinth series of sac and tubes that
conform to shape of bony labyrinth
* Fluids
* Perilymph – between bony and membranous labyrinth
* Endolymph - within membranous labyrinth

271
Q

Equilibrium receptors of the inner ear are called
the ?
* It has two functional parts:
1. Static equilibrium
2. Dynamic equilibrium

A

vestibular apparatus

272
Q

Receptors in the vestibule
* Report on the position of the head (static equil)
* Send information via the vestibular nerve

A

maculae

273
Q

In the ampulla of each semicircular canal
* Receptors that respond to angular or rotary
movements (dynamic equilibrium)

A

crista ampullaris

274
Q

cochlear duct

A

Vestibular membrane – separates cochlear duct
from scali vestibule
* Basilar membrane – separates cochlear duct from
scali tympani

275
Q

Located within the cochlear duct
* Receptors  hair cells on the basilar membrane
* Gel-like tectorial membrane is capable of
bending hair cells
* Cochlear nerve attached to hair cells transmits
nerve impulses to auditory cortex on temporal
lobe

A

spiral organ of corti

276
Q

mechanism of hearing

A

Vibrations from sound waves move tectorial
membrane
* Hair cells are bent by the membrane
* An action potential starts in the cochlear nerve
* Impulse travels to the temporal lobe
High-pitched sounds disturb the short, stiff fibers
of the basilar membrane
* Hair cells close to the oval window are stimulated
* Low-pitched sounds disturb the long, floppy
fibers of the basilar membrane
* Hair cells closer to apex are stimulated

277
Q
  1. receptors respond to sugars, saccharine,
    some amino acids?
    2 ? receptors respond to H ions or acids
    3 ? receptors respond to alkaloids
    4 ? receptors respond to metal ions
    5 ? receptors respond to the amino acid
    glutamate or the beefy taste of mea
A

1.Sweet receptors respond to sugars, saccharine,
some amino acids
2 Sour receptors respond to H ions or acids
3Bitter receptors respond to alkaloids
4 Salty receptors respond to metal ions
5 Umami receptors respond to the amino acid
glutamate or the beefy taste of mea

278
Q

receptor cells
* Possess ____ hairs
(long microvilli)
* Hairs are stimulated by
chemicals dissolved in saliva

A

gustatory cells
possess gustatory hairs

Impulses are carried to the gustatory complex
by several cranial nerves because taste buds
are found in different areas

279
Q

Taste buds are replaced
frequently by

A

basal cells

280
Q

Projections on surface of tongue are called

A

Papillae – projections on surface of tongue
* Filiform papillae—sharp with no taste buds
* Fungiform papillae—rounded with taste buds
* Circumvallate papillae—large papillae with taste buds

taste buds are primarily found on the sides of papillae

281
Q

taste buds house the receptor organs
* Locations of taste buds?

A
  • Locations of taste buds
  • Most are on the tongue
  • Soft palate
  • Cheeks
282
Q

Olfactory receptors are in what area and what do they do

A

Olfactory receptors are in roof of nasal cavity

  • Olfactory receptors cells (neurons) with long cilia
    known as olfactory hairs detect chemicals
  • Chemicals must be dissolved in mucus for
    detection by chemoreceptors called olfactory
    receptors
  • Impulses are transmitted carries on the olfactory
    nerve
  • Interpretation of smells is made in the cerebral
    cortex
283
Q

Taste and smell use what receptors?

A

Both senses use chemoreceptors

  • Stimulated by chemicals in solution
  • Taste has at least four types of receptors
  • Smell can differentiate a large range of chemicals
  • Both senses complement each other and
    respond to many of the same stimuli
284
Q

spinal cord anatomy: spinal nerves leave at the level of each vertebra

A

Dorsal (posterior) roots
Sensory fibers

Cell bodies of these neurons found in the
dorsal root ganglia

Ventral (anterior) roots

Contains motor fibers

Cell bodies of these motor neurons are found in anterior horn

285
Q

what are PNS

Structure: multipolar neurons

Cell body within PNS

Carry impulses from the PNS to viscera,
muscles, or glands

A

Motor (efferent) neurons

286
Q

what are Found in neural pathways within the central
nervous system

Structure: multipolar neurons

Some cell bodies in nuclei of CNS

Connect neurons

A

Interneurons (association neurons)

287
Q

Sensory receptor
what do different ones do?

A

Sensory receptor
Specialized dendritic endings, cell or complex
structures

Provide information about internal and
external environment

Sensory receptors in skin and viscera –
temperature, touch, pain, pressure

Proprioceptors

Detect stretch or tension in muscles,
tendons, joints

Gives information on body position

288
Q

Portion of Schwann cell
that contains most of the
cytoplasm and nucleus

A

neurilemma

only on myelinated axons

bio110 (11 decks)

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