Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BIO 225 > Exam 2 > Flashcards

Exam 2 Flashcards

1
Q

How is a membrane potential established

A

It arises from the unequal distribution of ions (inside of the cell is more negative, outside is more positive)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is equilibrium potential

A

The membrane potential at which the net flow of ions is zero

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How is membrane potential maintained

A

Na+/K+ pump and leaky channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is depolarization

A

Membrane potential increases caused by cations entering or anions exiting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is hyperpolarization

A

Membrane potential decreasing caused by cations exiting or anions entering

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Reception zone of the neuron

A

Incoming signals are received in dendrites and converted to a change in membrane potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Integration zone of the neuron

A

A change in membrane potential initiates action potentials in the axon hillock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Conduction zone of the neuron

A

Action potentials are conducted to axon terminals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Signal transmission zone of the neuron

A

Neurotransmitter release transmits a signal to the target cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Graded potentials

A

Caused by ligand gated ion channels (more ligands, more depolarization)

Transient signals that occur at a specific location

Short distance

Vary in magnitude and direction

Stronger stimuli=stronger depolarization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Action potentials

A

All or none

Spatial summation - graded potentials close together which increases threshold

Temporal summation - increasing membrane potentizl little by little

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Threshold

A

Membrane potential required to initiate an action potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Absolute refractory period

A

The time when another action potential cannot be triggered

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Relative refractory period

A

The time when a much stronger stimuli is required to trigger action potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Relationship of stimulus strength to axon potentials

A

Stronger stimulus = higher frequency of AP’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Key events of neurotransmitter release

A

Synthesized in neuron, released at pre-synapse following depolarization, bind & cause effect at post-synapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Sensory neurons

A

Afferent
Unipolar
Trigger zone at interface between dendrites and axon
Carry impulse from PNS to CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Interneurons

A

Connect one neuron to another, multipolar and have many terminals, unmyelinated, many dendrites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Motor neurons

A

Efferent, multipolar, carry signal from CNS to target organ to elicit a response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does myelination increase action potential conduction speed

A

It restricts the action potentials to the nodes of ranvier which forces electronic spread through the internodes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How does large-diameter axons increase action potential conduction speed

A

They decrease resistance to electrical current flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Ionotropic vs metabotropic

A

Ionotropic are receptors that open/close upon a neurotransmitter binding

Metabotropic is when a neurotransmitter binds to a receptor and causes a signal transduction to occur which causes the opening/closing of a different channel elsewhere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Tonic receptors

A

Decrease response to stimulus as duration increases (ex. sitting down)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Phasic receptors

A

Firing many action potentials all at once and then stops and quickly adapts to stimulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Sensory stimuli types
Chemoreceptors: presence of chemicals in environment Mechanoreceptors: detect pressure and movement Photoreceptors: detect light Thermoreceptors: detect temperature Electroreceptors: detect electric fields Magnetoreceptors: detect magnetic field
26
Unimodal
One particular afferent neuron is associated with one type of receptor
27
Polymodal receptors
sensitive to multiple modalities, overlapping receptive fields, lateral inhibition
28
Lateral inhibition
Suppresses signals from neighboring neurons which enhances the focus on the strongest stimuli and prevents overlap
29
Dynamic range
The difference between the maximum and minimum stimulus intensities a sensory system can detect and encode
30
Range fractionation
Encodes a wide range of stimulus intensities via high and low threshold receptors
31
Logarithmic encoding
Distinguishes between low intensities with sight and hearing weight
32
Discrimination
Distinguishes between different stimuli based on intensity, location, modality, or duration
33
Exteroception
external to body (mouth/nasal passages) and includes olfaction, gustation, nocioception, and pheromones
34
Interoceptors
Internal to body (blood pH, chemosensors in the stomach)
35
Olfaction
Smell ORNs express GPCRs single odorant GPCR
36
Gustatory
Taste GPCRs to detect sweet and bitter
37
Nicotinic receptor
Acetylcholine receptor in the neuromuscular junctions, ganglionic neurons, and adrenal medulla (ionotropic)
38
Muscarinic receptors
Acetylcholine receptor in the gut, heart, bronchioles, sweat glands, and skeletal muscle (metabotropic)
39
A1 receptor
Adrenergic receptor that causes vasoconstriction in smooth muscle
40
A2 receptor
Adrenergic receptor that inactivates calcium channels and reduces the release of NE
41
B1 receptor
Adrenergic receptor that activates calcium channels and increases muscle contraction in cardiac muscle
42
B2 receptor
Adrenergic receptor that reduces muscle contraction and causes vasodilation
43
Signal transduction pathways in olfactory receptor cells
1. Odorant binds to odorant receptor which causes a conformational change 2. G-protein is activated and G(olf) moves through membrane and activates adenylate cyclase 3. Adenylate cyclase converts ATP into cAMP 4. cAMP opens cAMP gated ion channels 5. Ca2+ and Na+ enter the cell causing generator potential 6. Ca2+ opens Ca2+-activated Cl- channels causing Cl- to exit the cell causing depolarization 7. Generator potential opens voltage-gated Na+ channels triggering APs
44
Sweet signal transduction
1. Sweet substance binds to receptor, causes conformational change 2. Activated G-Protein activates adenylate cyclase 3. Adenylate cyclase catalyzes ATP to cAMP 4. cAMP activates protein kinase that phosphorylates and closes K+ channel 5. Depolarization opens voltage gated Ca2+ channels 6. Influx of Ca2+ causes neurotransmitter release
45
Bitter signal transduction
1. Bitter substance binds to receptor, causes conformational change 2. Activated G-Protein activates phospholipase C (PLC) 3. PLC catalyzes conversion of PIP2 into 2nd messenger IP3 4. IP3 causes release of Ca2+ from intracellular stores 5. Influx of Ca2+ causes neurotransmitter release
46
Salty signal transduction
1. Na+ from salty foods enters through Na+ channels 2. Resulting depolarization opens voltage gated Ca2+ channels 3. Influx of Ca2+ causes neurotransmitter release
47
Sour signal transduction
1. H+ from sour foods block K+ channel 2. Blockage prevents K+ from leaving cell 3. depolarization opens voltage-gated Ca2+ channels 4. Influx of Ca2+ causes neurotransmitter release
48
Structures that mediate mechanosensation in touch
They are located outside of the body, merkel's disks (tonic), ruffini corpuscle & pacinian corpuscles (phasic), free nerve endings
49
Structures that mediate mechanosensation in proprioception
golgi tendon organ (relaxtion), muscle spindle fibers (contraction)
50
Signal transduction in hair cells
Higher K+ outside, higher Na+ inside Mechanically gated K+ channels are attached to afferent sensory neuron TRP's open when kinocillium move to the right, K+ rushes in and stimulates AP, Ca+ channels and neurotransmitter is releases TRP's close when kinocillium moves toward the right
51
Utricle
Detect movements of otolithic membranes up and down
52
Saccule
Detect movements of otolithic membranes side to side
53
Semicircular canals
Cupula recognizes rotation
54
Cochlea
Amplify and transduces basilar membrane movement
55
Pinna
Protects ears
56
Tympanic membrane
Ear drum, vibrates sound in & out
57
ossicles
Bones move in and out
58
What makes up the vestibular apparatus
Utricle, saccule, semicircular canals
59
Organ of corti
Recognizes volume and frequency
60
Cornea
fixed, refocuses light
60
Ciliary photoreceptors
Resting membrane potential at -30mV, when stimulated it is hyperpolarized Composed of rods and cones Expresses c-opsins via Gi
60
Aqueous humor
watery liquid
60
Iris
colored part
60
Rhabdomeric
Has resting membrane potential higher than neurons More light = taller depolarization Conformational change induces G-protein signaling
61
Lens
focuses light
62
Cilliary bodies
contract to change focus of light on the eye
63
Pupil
focuses
64
Vitreous humor
Thick liquid (transmits light)
65
retina
photo sensors
66
fovea
location of focus center
67
optic disk
nerve location
68
choroid
dark pigmented, reflects light
69
Rods
Converge onto one nerve and are on or off Rod -> bipolar cell -> ganglion cell -> optic nerve Sensitive to dim light controls Brightness
70
Cones
Cone shaped Sensitive to bright light Color sensors
71
Pathway of stimulus to effector
Internal/ecternal sensory stimuli -> afferent neuronss -> CNS -> efferent neurons -> motor or autonomic pathways -> body systems
72
Division of autonomic nervous system
Sympathetic, parasympathetic, enteric
73
Afferent vs efferent
Afferent receives the stimuli from internal and external sensory stimuli Efferent receives message from spinal cord to signal to rest of body
74
How are neurons related to nerves
Many neurons make up one nerve
75
What are tracts
Bundles of axons in the CNS
76
Ascending vs descending tracts
Ascending is sensory/afferent information, descending is motor/efferent information
77
Dura mater
tough, outermost layer of spinal cord
78
Arachnoid
weblike, middle layer of spinal cord
79
Pia mater
delicate matter, thing inner layer of spinal cord
80
Ipsalateral vs contralateral
same side vs opposite side
81
Sympathetic nervous system
Stress, excitement, physical activity, fight or flight, increases HR
82
Parasympathetic nervous system
Active during rest, resting and digesting, maintenance activites
83
Enteric nervous system
Digestion
84
Sympathetic vs parasympathetic
Parasympathetic: preganglionic neuron long, postganglionic short, ACH, Muscarinic receptors Sympathetic: preganglionic neuron is short, post ganglionic is long, NE, adrenergic receptors
85
Relationship between parasympathetic and sympathetic branches
Antagonistic

BIO 225 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions