3 Flashcards
(84 cards)
1
Q
The Motor Unit
A
One motor axon and all the muscle fibers it innervates
2
Q
What is the basic unit of movement
A
The Reflex
3
Q
What does closed-loop mechanism maximize
A
Accuracy
4
Q
What transmitters is used at the neuromuscular junction
A
ACH
5
Q
What is the neuromuscular junction?
A
Where the motor neuron axon innervates the muscle fiber
6
Q
The size principle of motor neruon recruitment
A
Strong contraction =large fast twitch fibers.
Weak contraction =small slow twitch
7
Q
Fibers that lie within the muscle spindle are known as what
A
Intrafusal
8
Q
What has a low innervation ratio
A
fine movements such as in fingers
9
Q
What does poliovirus destroy
A
Motor neurons in brain stem and Spinal cord
10
Q
What do Golgi tendon organs report
A
Contraction and tension
11
Q
Sperm and ova are known as what and what do they form when fused
A
Gametes, and zygote
12
Q
What does the SRY gene code for?
A
SRY protein that differentiates the gonad into the testes
13
Q
In mammals, whether the body develops in a male or female pattern depends mostly on…
A
Testosterone
14
Q
What are the stages of reproductive behavior?
A
- Sexual attraction
- Appetitive Behavior
- Copulation
- Post Copulatory Behavior
15
Q
Which of the following factors is most important in determining whether an adult male rat and a female rat will mate?
A
Willingness of the female
16
Q
Animals born in a rather early stage of bodily development are called
A
Altricial vs the more developed precocial
17
Q
What does the organizational/activational Hypothesis state
A
a single steroid signal masculinizes the body, the brain during development and activate later in adulthood the associated behaviors
18
Q
Sexual receptivity often corresponds with ovulation in female mammals and it is necessary for ____________.
A
Copulation
19
Q
What does the Vomeronasal organ in rats detect?
A
Pheromones
20
Q
What will a proceptive female do?
A
perform different behaviors to attract a male
21
Q
What are the phases of response in human sexual behavior?
A
excitement, plateau, orgasm, and resolution
22
Q
What is 5alpha reductase important for developing?
A
external genitalia in males
23
Q
How are muscles attached to the bone?
A
Special tissue connects the muscle and bones, holding them together
24
Q
Which sensory organ forms the proprioception system?
A
Spindle systems(length) and Golgi organs(tension)
25
Coolidge effect
no refractory phase when exposed to novel female
26
What is the main coordinator of male sexual behavior
Medial pre-optic area
27
At what age foes the early gender identity occur?
3-4 years of age
28
where does the expression of the gene SRY occur
Pregonads to turn them into testes
29
Does REM increase with age?
no it decreases dramatically very early and then more as a senior.
30
In humans , the free running period is
longer than 24 hours
31
tau mutation is hamsters is results in what?
short circadian cycle, one mutation 2 hour less, two =4 hour less
32
Motor plan
a set of muscle commands established before the action occurs, like in speech
33
Ramp movements
Slow , sustained motions
34
Striated muscles and their two types
under voluntary control, Fast-twitch, slow-twitch
35
Primary motor cortex's relationship with the nonprimary cortex
Primary intitiates command
| Non primary intitiates cortical processing
36
Meaning of final common pathway
Motoneurons are the final pathway which the brain and spinal cord can control muscles
37
Two receptor endings for muscle spindles
Primary:Wrap center and are dynamic, sensitive early in a stretch
secondary:Wrap ends and are static, they change rate slowly, more sensitive to maintained length
38
What are the two factors affecting muscle stretch
THe rate of change of muscle length,
| The necessary force exerted to maintain the desired activity.
39
Gamma motoneurons(efferents)
alter tension withing hte spindle and control receptor sensitivity, contrast to alpha motoneurons for extrafusal muscle fibers.
40
Function of golgi tendon organ,
Responsive to muscle contraction and when stimulated inhibits motoneuron action on muscles to prevent damage.
41
afferent
Bottom up
42
efferent
top-down
43
Pyramidal (corticospinal) system
From cortex to spinal cord through brain stem at the pyramid of the medulla, cross at decussation in medualla, split into left side and right where opposite cortex controls
44
EXtrapyramdal system
Reticulo spinal tract and rubrospinal tract. Former originates in reticular fomration and the latter in the red nucleus of the midbrain.
45
Nonprimary cortex
anterior to M1 and has SMA and premotor cortex modulates M1
46
SMA
supplementary motor area, receives some input from basal ganglia initiates sequences of movements and PLANNING movements that are internally generated.
47
Premotor cortex
anterior to the primary motor cortex, directs movement in response to external cues
48
Reticulospinal tract
originates in reticular formation and has inhibitory and excitatory effects
49
Rubrospinal tract
Red nucleus of midbrain. is involved in motor output
50
Cerebellum in motor control
Cerebellar cortex purkinje cells guide movement through inhibition. important for repeated and skilled movements.
51
Basal ganglia and cerebellum correlations with cortical areas
The cerebellum lines up with SMA to monitor ongoing activity and produce smooth movements
Basal ganglia lines up with M1 to initiate and terminate movements
52
explain stretch reflex
Weight added, muscles stretched and afferents in spindle are excite, go directly to motor neurons that control the stretched muscle then stimulate the muscle to oppose muscle streth
53
Pheromones and how they guide sexual behavior
male rats have VNO which sends signal to medial amygdala then mPOA, allows communicaion for
54
How is parental behavior in rodents studied?
parabiotic exchange showed hormones induce parental behavior in mice
55
Sexual differentiation
The process by which individuals develop male or female bodies and behavior
56
Sexu determination
early developmental event that decides if a fetus will be male or female
57
What does SRY, Test, AMH and DHT do for humans?
SRY-differentiates gonads to testes.
TEST-promotes development of wolffiean system
AMH-induces the regression of the mullerian system(ANTI-MULLERIAN)
DHT-external genitalia by 5a reductase from TEST
58
What are the different malformations of the sexual organs?
Turners- one X ,slow growth, hearing loss, retardation
CAH- result of female exposure to androgens before birth
Cloacal exstrophy-boys born with testes but no penis
AIS-occurs in XY with no androgen receptors
59
How can gender be defined?
Chromosomal, Gonadal, Hormonal, MOrphological, Behavioral (the most difficult to place down)
60
What is the organizationala nd activational effect of hormones
1st is a permanent alteration of behavior( through nervous system) while activational is temporary
61
How does testosterone and estrogen masculinize the brain during development
Aromatization hypothesis
62
Alfa-fetoprotein in females
Blocks maternal estrogen from entering the brain , test is the bypass in males that gets converted into estradiol by Aromatase
63
Define Sexual dimorphism
Male and females are different. male birds have larger syrinxes. Male rats have larger POA (SDN-POA)
64
How are motoneruons in the spinal cord affected by test during development.
motoneurons that control BC muscles are receptive to testosterone and cause secretion of trophic(CNTF) factors.
65
Possible biological and cultural factors for sexual orientationa
Guevedoces show alteration of behavior (female to male) at puberty so it may be neonatal, prenatal, or at the second sensitive period
66
What factors may play a role in homosexuality in humans?
some brain structures are noticable larger in heterosexual , INAH-3. This can just be an indicator of early influences from certain hormones or socially.
67
WHat is circadian, infradian, and ultradian?
circadian is the daily rhyhym, infradian is longer than circadian, ultradian is shorter than circadian
68
Zeitgeber
the light stimulus that entrains the circadian cycle
69
SCN
the suprachiasmatic Nucleus of the hypothalamus takes signals directly from the optic nerve to set the circadian cycle by way of the retinohypothalamic pathway. hamster experiments prove
70
how did fruit flies affect the discovery of the internal clock.
allowed discovery of genes responsible for rhythym
71
how does the mammalian molecular clock work?
1. CLock and BMAL1 bind together to a dimer that enhances transcription of Per and Cry genes. Here also glutamate form RNH pathway is introduced to enhance transcription of Per
2. The per and cry proteins inhibit production of more per and cry for around 24 hours
72
What are different approaches to study sleep rhythyms
EEG, EOG EMG
73
Stages and characteristics of reNREM
15-20 hz low amp waves- beta activity or desynchronized eeg
8-12 hz is alpha rhythm which is where relaxation occurs
74
stages and characteristics of NREM
Vertex spikes at stage 1
12-14hz waves called sleep spindles and k complexes is stage 2
-If awakened here people will deny that they were asleep
SWS when 1 hz large amp delta waves are present. This stage is likened to chanting and is stage 3. GH is also most eminent here.
75
Stages and Characteristics of REM
EEG similar to wakefulness but totally flaccid musculature.
76
Night terrors vs. Nightmares vs. Dreams.
terrors are sudden arousal's. nightmare and dreams are on in the same
77
Dreams in early development
largee amount of REM and short sleep cycles in infants. and are able to slip immediately into REM. REM experiences may provide stimulation that is essential for maturation of the brain
78
How do sleep patterns change over the span of life.
total sleep declines with age ;
79
Evolutionary aspects of REM SLEEP and which animals don't have REM
REM arose in a common ancestor to reptiles, birds, and mammals.
80
4 functions of sleep
1. niche adaptation
2. Energy conservation- carnivores more than omnivores more than herbivores
3. Body restoration
4. memory consolidation.
81
What are the different brain areas involved in sleep and what are their roles?
1. basal forebrain generates SWS by regulating GABA ergic neurons that send signals to tuberomammillary nucleus that promotes sleep and brainstem
2. Reticular formation wakes up the forebrain and is inhibited by the forebrain
3. pontine system introduces REM at the subcoeruleus that uses GABA and Glycine to inhibit motor neurone
4. Hypothalamic system uses hypocretin to keep slepp at bay and prevent the direct transition from wakefulness to REM . axons from here go to all of the above systems.
82
Explain narcolepsy and sleep walking
narcolepsy tends to jump immediately into REM and can show sudden cataplexy. caused by an interference in hypocretin signalling
83
What are the most common sleeping disorders
sleep enuresis. bed wetting. Somambulism. sleep walking. Rem Behavior disoder has lesions in subcoeruleus
84
What is sleep apnea.
a sleep disorder where respiration slows or stops periodically
