QUIZZAM 10 Flashcards
Autonomic Nervous System
PNS functions w/o conscious effort
ANS Regulations
heart rate, blood pressure, breathing rate, and body temp
ANS Characteristics
- preganglionic fibers
- ganglia
- postganglionic fibers
Parasympathetic
‘rest and digest’
ordinary conditions
Sympathetic
‘fight or flight’
stressful or emergency conditions
Structural Differences btwn parasym. and sym.
- origin sites
- fiber length
- ganglia location
- ganglia types
Dual Innervation
when visceral organs receive info from both para and sym ANS divisions
Autonomic Plexuses
nerve networks formed from sym postganglionic fibers ‘mingle’ with para preganglionic fibers
photoreceptors
rods and cones
Rods
dim light and no color
Cones
bright light and high color vision
Light is refracted…
- at the cornea
- entering the lens
- leaving the lens
Lens
precise focusing of light
Close Vision requires…
- Accommodation
- Constriction
- Convergence
Accommodation
changing of lens shape by ciliary muscles to increase refraction power
Constriction
pupillary reflex constricts the pupil
Convergence
medial rotation of the eyeballs toward objects being viewed
When lights are off…
photoreceptor cell (rods) says don’t send signal to bipolar cell –> ganglion doesn’t send signal
When lights are on…
photoreceptor cells (rods) don’t tell bipolar cells to not send signal (they don’t say anything) –> ganglion sends signal
Thalamic Processing
- relays info on movement
- segregates the retinal axons in preparation for depth perception
- emphasizes visual inputs from regions of high cone density
- sharpens contrast info
Cortical Processing
- Striate cortex (primary)
- Prestriate (visual association)
What processes identification of objects?
temporal lobe
What determines spatial location?
parietal cortex
Chemical sense
taste and smell
Types of tastebuds
- Circumvallate
- Foliate
- Fungiform
Basic taste sensations
- sweet (sugars, alcohol)
- sour (H ions)
- salt (metal ions)
- bitter (alkaloids)
- umami (amino acids)
In order to be tasted, a chemical…
- must be dissolved in saliva
- must contact gustatory hairs
Binding of the food chemical…
- depolarizes the taste cell membrane, causing release of neurotransmitter
- initiates a generator potential that elicits an action potential
Taste Transduction
- taste is 80% smell
- thermo-, mechano-, and nociceptors in the mouth also influence tastes
- temp and texture enhance or detract from taste
Parts of the Ear
- External ear
- Middle ear
- Internal ear
Properties of Sound Waves
- frequency - # of waves
- wavelength - distance btwn two crests
- amplitude - height of crests
- pitch - perceptions of different frequencies
- loudness - sound intensity (decibels)
Localization
intensity and timing of sound waves reaching both ears
Nervous System
short term effects and regulates glands and muscles
Endocrine system
long term effects and influence metabolic activity by means of hormones
Communication by Cells
- direct communicaiton (gap junctions, directly to next cell)
- autocrine (extracellular fluid, back to itself)
- paracrine (extracellular fluid, to another cell)
- endocrine (bloodstream, to another cell)
Exocrine vs Endocrine
exocrine - into ducts, sweat and digestive glands
endocrine - directly into bloodstream, “target cell”
Hormone Characteristics
- needed in very small amounts
- produce long-lasting effects in cells they target
- regulate metabolic processes
- regulated by negative feedback mechanisms
Hormone Functions
- stimulate synthesis of an enzyme/protein by activating genes in target cells
- increase/decrease the rate of enzyme/protein by changing transcription or translation rates
- turns enzyme or membrane channels “on” or “off”
Freely circulating hormones…
- diffuse out of bloodstream or bind to receptor
- are broken down by the liver or kidney
- are broken down by enzymes in blood plasma
Endocrine Reflexes
- humoral stimuli (thyroid)
- hormonal stimuli (pituitary gland)
- neural stimuli
Anterior Pituitary Gland secrete…
- human growth hormone - cell growth and replication
- thyroid stimulating hormone - secretion of hormones by the thyroid gland
- adrenocorticotropic hormone - release of steroid hormones and glucose metabolism
- prolactin - mammary gland, development, and milk
- follicle stimulating hormone - primary sex organs and maturation
- luteinizing hormone - primary sex organs and secretion of estrogens and testosterone
Posterior Pituitary Gland
- anti-diuretic hormone - decrease water loss in kidneys
- oxytocin - pregnancy stuff and pleasure
Thyroid Gland Hormones
- thyroxine (T4) - metabolic rate
- triiodothreonine (T3) - metabolic rate
- calcitonin - calcium
Adrenal Glands
highly vascularized
two parts:
1. adrenal cortex - aldosterone and cortisol
2, adrenal medulla - epinephrine and norepinephrine
Pineal Gland
epithalamus
melatonin
functions:
1. awake/sleep cycle
2. inhibiting reproductive function
Pancreas
- alpha cells - glucagon (blood glucose levels)
- beta cells - insulin (promote glycogen formation)hj