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Bio 231 Cumulative Final

Terms in this set (40)

Define homeostasis and detail examples of physiologic regulation of homeostasis used in the lecture (example: thermoregulation)
Homeostasis: Ability to maintain consistent internal environent.
Thermoregulation-Negative Feedback Loop: (Stimulus) Cold temperature lowers body temp below normal ->(Receptors) Sensory receptors in skin detect cold -> (Control Center) Hypothalamus compares sensory info regarding temp decrease to normal body temp 37 degrees C, directs response to effectors -> (Effectors) Vasoconstriction in skin, inactivated sweat glands, skeletal muscles shiver to generate heat-> (Homeostasis) Body temp back to normal
Describe the layers of the skin by stating what tissue type composes each layer, from superficial to deep.
Stratum Corneum
Dead, no nucleus, keratin filled keratinocytes

Stratum Lucindum (thick skin)
Stratum Granulosum
Last living, keratinization occurs in this layer
Stratum Spinosum
Epidermal dendritic cells present
Stratum Basale
Keratinocytes-stem cells that make Keratin
Melanocytes- make and store melanin
Merkel Cells (tactile)-sensitive to touch

2.) Dermis (2 LAYERS)
a.) Papillary Layer
(i) Areolar CT-forms dermal papillae; has capillaries and tactile recptors
b.) Reticular Layer
(ii) Dense irregular CT- surrounds/supports hair follicles, sebacious glands, sweat glands, nerves, blood vessels

3.) Subcutaneous
a.) one layer; composed of areolar and adipose CT
For a given cell type, state a primary function.
Melanocyte- Stratum Basale: Produce and store melanin
Keratinocyte- Stratum Basale: make keratin cells
Langerhans Cells-Found mostly in Stratum Spinosum- immune cells
Merkel Cells-Stratum Basale: tactile touch
Define what is a hormone and compare the three methods of stimulus for hormone release.
Hormone: Chemical formed by an endocrine gland and transported by the blood to its target organ to alter cellular activity.
Three methods of stimulus of hormone release: HORMONAL, HUMORAL, NERVOUS SYSTEM.
Hormonal: Release of another hormone stimulates release of another (e.g Anterior pituitary releases TSH-thyroid stimulating hormone- to stimulate the thyroid to release TH-thyroid hormone.
Humoral: Changes in levels of nutrients or ions in blood triggers release of hormones (e.g blood glucose levels increase so pancrease is stimulated to release insulin)
Nervous System: Stimulation by the nervous system triggers release of hormones (e.g Fight or flight)
Determine which molecular class a given hormone is: amino acid or steroid, based on a description, given location, or visual aid.
Amino Acid Hormones: Proteins (most hormones), "Tyr" based
Hydrophilic, unbound transport
Target interaction: Extracellular pathway- i.e cAMP ( 2nd Messenger)
Steroids: Sysnthesized from cholesterol, gonadal and adrenocrotical
STEROIDS TO MEMORIZE: Estrogen, Testosterone, Progesterone, Cortisol, Aldosterone
Hydrophobic: requires protein for transport (bound)
Target interaction: intracellular pathway
Makes new protein as result of meeting between steroid and cell
List all major endocrine organs and the hormones they produce, and name biologic targets (organs, cells, etc.).
Anterior Pituitary Gland Hormones: (TP-FLAG)
T=Thyroid Stimulating Hormone-
Target:Thyroid
Effect: Thyroid gland releases thyroid hormone
P= Prolactin-
Target: Mammary Glands
Effect: regulates mammary growth and milk production
F=Follicle Stimulating Hormone
Target: Ovaries/Testes
Effect: controls development of both oocyte and ovarian follicle within ovaries , controls development of sperm
L=Luteinizing Hormone
Target: Ovaries/Testes
Effect:induces ovulation, controls testosterone synthesis within testes
A= Adrenocorticotropic Hormone
Target: Adrenal Cortex
Effect: stimulates adrenal cortex to release corticosteroids (e.g cortisol)
G=Growth Hormone
Target: All cells
Effect: release opf insulin like growth factors (IGF) from liver- works synergistally with GH to induce growth
Pineal Gland
Melatonin
Target: Brain
Effect: regulates body's circadian rhythm, functions in sexual maturation

Hypothalamus
Antidiuretic Hormone (ADH)
Target: Kidney, Hypothalamus (thirst center), Blood Vessels
Effect: Stimulates kidneys to decrease urine output, and thirst center to increase intake of water, is a vasocontrictor
Thyroid Gland
Thyroid Hormone
Target: All Cells
Effect: increased metabolic rate of cells, increased heat production
Calcitonin
Target: Bone, Kidneys
Effect: decreases blood calcium levels
Parathyroid Glands
Parathyroid Hormone (PTH)
Target: Bone tissue, Kidneys
Effect: Increases blood calcium levels by stimulating release of calcium from bone tissue and decrease of calcium loss in urine- causes formation of calcitriol (vit D) to absorb more in small intestine
Adrenal Cortex
Mineralcorticoids (e.g Aldosterone)
Target: Kidney
Effect: Regulates blood Na+/K+ levels by increasing urine output of K+ and decreasing output of NA+
Glucocorticoids (e.g Cortisol)
Target: Liver, Adipose CT, All cells
Effect: Participate in stress response- increase glucose levels available in blood
Gonadicorticoids (DHEA)
Target: Various body cells
Effect: Stimulates maturing and function of reproductive system
Adrenal Medulla
Epinepherine/Norepinipherine
Target: Various Cells
Effect: Prolongs the effects of the sympathetic division of the autonomic nervous system
Thymus
Thymosin
Thymulin
Thymopoietin
List the meninges in order from superficial to deep, state where cerebrospinal fluid (CSF) is produced, explain its circulatory pathway, and general functions.
Dura mater made of dense CT-2-ply toilet paper (periosteal and meningeal layers). Blood can drain between the two plys (called the dural venus sinus)
Arachnoid mater made of loose CT-web-like structure. CSF can flow in the subarachnoid space
Pia mater made of areolar CT. covers brain surface
CSF is produced in the choroid plexuses within the ventricles. Choroid plexus is made of ependymal cells and blood capillaries in the pia mater. Blood plasma is filtered across capillary walls and pia mater; modified by the ependymal cells.
CSF flow: lateral ventricle to 3rd ventricle to cerebral aqueduct to 4th ventricle to sub arachnoid space to dural venus sinus to internal jugular vein to heart.

CSF functions: buoyancy, protection, ECF stability
Problem solve mechanisms for developing hydrocephalus and coup/countercoup injuries.
Hydrocephalus can be addressed with shunts to drain CSF. Coup/countercoup injuries are like in car crash-frontal lobe hits skull, bounces back and occipital lobe hits skull.
Describe the form and function of the blood brain barrier (BBB).
BBB made of astrocyte class of neuroglial cells. Perivascular feet wrap around capillaries. Endothelial cells of BBB capillaries contain tight junctions and a thickened basement membrane. Prevents toxins, pathogens, waste products, and many solutes from entering interstitial fluid. Allows nutrients, some ions and lipid-soluble stuff to cross (gasses, alcohols, etc.)
Correlate primary cerebral lobes/regions to regional (localized) functions, including special senses, motor and general sense, and Broca's/Wenicke's areas.
Frontal lobe (posterior to anterior): primary motor cortex, frontal eye field, Broca's area (motor speech; issue would be expressive aphasia), prefrontal cortex (reasoning, intellect, emotion)
Insula: primary gustatory cortex; associate taste with emotion; in the parietal/temporal lobes
Parietal lobe: Primary somatosensory cortex, somatosensory association area. Includes Wernicke's area responsible for speech comprehension (issue would be receptive aphasia)
Temporal Lobe: primary auditory cortex, primary olfactory cortex (anterior to auditory cortex). Auditory association area (inferior to cortices; localization).
Occipital lobe (posterior to anterior): primary visual cortex, visual association area
Language lateralized to left hemisphere
Predict where somatic function is lost given a specific locus of damage to the homunculus.
Motor homunculus: medial side of frontal lobe controls below the waist
Sensory homunculus: lateral side of parietal lobe is above the waist
Identify and provide specific functions for the following deep brain regions: basal nuclei (ganglia), diencephalon (including thalamus, hypothalamus, pineal body), brainstem (midbrain, pons, and medulla oblongata), and the cerebellum.
Basal nuclei: deep masses of gray matter regulate motor output initiated by cerebral cortex. Receive plans from a cortex, adjust, send to the thalamus, thalamus sends that back to the cortex
Diencephalon: encloses the third ventricle; Thalamus is the relay point-processes sensory info and sends it to the correct location of the cortex; not everything gets through. Hypothalamus is the homeostasis master. Pineal gland produces melatonin
Brainstem: connects the brain to the spinal cord; Midbrain contains CN III (oculomotor) and IV (trochlear), the superior peduncles, substantia nigra (dopamine producers), the cerebral aqueduct (CSF flow), and corpora quadrigemina (visual and auditory pathway coordinator). The pons contains CNs V-VIII, the pneumotaxic center, and relays impulses between the cortex and cerebellum. Medulla oblongata contains pyramids for decussation, the autonomic motor reflex centers and CNs IX-XII
Compare the specific types of motor function controlled by the basal ganglia v. cerebellum.
Cerebellum controls posture, balance, coordination, and fine motor control. Cerebellum sends corrective feedback to basal ganglia
State which central neurotransmitter is affected by Parkinson's disease, name the location and nuclei which produce it, and the functional motor consequence of "low" levels of the neurotransmitter.
Dopamine. Basal nuclei of substantia nigra in midbrain. No inhibition of spiny neurons (an inhibitor)=lots of IPSP in corticospinal tract=difficulty in voluntary movement
List the many homeostatic processes controlled by the hypothalamus.
ANS control, endocrine system, body temp, food and water intake, circadian rhythm, emotions
Explain what is meant by the statement, "the thalamus is the sensory relay station".
Sensory nervous signals from conscious senses (except olfaction) synapse at the thalamus. That info is processed, and if the thalamus thinks it's important, it is sent to the proper cortex.
Describe the functional roles of the three "vital centers" housed in the medulla oblongata.
Cardiac (heart rate and force of contraction), vasomotor (contraction and relaxation of smooth muscle in arterioles), and respiratory (rhythmic breathing). Also can control vomiting, hiccuping, swallowing, coughing, sneezing
Locate and describe the functional role of the reticular activating system (RAS)
Diencephalon, midbrain, and gray matter in spinal cord. Sensory inputs from visual, auditory, and general sensory tracts to motor output responsible for alertness, focus, and arousal from sleep
Identify an abnormal EEG pattern given a functional state (i.e. during an active and awake state what should the waveform pattern be?). And do the same task for a graph of sleep stages.
Frequency of brain waves decreases from awake to deep sleep
Describe the three strategies for consolidating Short term memory data into LTM (long term memory). What does "long term potentiation" mean?
Excitement, repetition, and association. Long term potentiation is the
strengthening of a synapse over a period of time
For each cranial nerve (CN): name, number, and identify which information type it transmits. Explain how CNs differ from spinal nerves for information transmission.
I: Olfactory-Sensory (some)
II: Optic-Sensory (say)
III: Oculomotor-Motor (marry)
IV: trochlear-Motor (money)
V: trigeminal-Both (but)
VI: abducens-Motor (my)
VII: facial-Both (brother)
VIII: vestibulocochlear-Sensory (says)
IX: glossopharyngeal-both (bad)
X: vagus-both (bitches)
XI: accessory-motor (make)
XII: hypoglossal-motor (money)
Explain the four "bits" of information that receptors encode into the transduced signal: modality, location, intensity, and duration.
Modality: mechano, chemo, thermo, nocio, EM
Location: Large field sizes are less precise
Intensity: stronger stimulus=higher Hz of AP
Duration: Longer duration=lower Hz of AP
Describe a typical therapeutic approach to reducing pain, at the four locations identified in the "pain" exercise (slide 23).
NSAIDs and ice prevent the AP from initiating in first order neuron
Drugs like novocaine stop the AP from propagating down the first order neuron's
axon (it is a sodium voltage gated channel blocker)
At the synaptic cleft between first and second order neurons, opioids and
morphine break down the NT
Meditation can modulate 2nd or 3rd order neurons
Explain why a non-noxious mechanical stimulus is theorized to modulate pain inputs.
Gate control theory: Interneuron inhibits pain perception. Nociceptor responds to
noxious stimulus by inhibiting interneuron, so pain goes to the cortex . Mechanical
stimulus initiates EPSP to counter the gate
Describe the general somatic motor pathway using the corticospinal tract as an example. This includes the names and locations of the CNS and PNS nerve cell bodies, usual location of decussation, and the neurotransmitter used at the effector synapse.
Upper motor neuron body in primary motor cortex. Axon extends through interna
l capsule, cerebral peduncle, decussates in pyramids in medulla, terminate in
gray matter in the spinal cord. Lower motor neuron body in the anterior horn of spinal cord, exits through anterior root, and innervates specific skeletal muscle. Acetylcholine as an NT
Explain the general neurological pathway for transmission of sensation: receptor level, circuit level, and perception level.
Receptor level: nerve endings, corpuscles to dorsal horn (afferent)
Circuit level: through the spinal cord to brain stem then thalamus
Perception level: Thalamus sends signal to appropriate location on sensory homunculus
Define the term "transduction" and provide a specific example for each special sense.
Transduction is when one kind of signal/stimulus is converted to another
Olfaction (chemo): Olfactory receptor activated by chemical stimulus initiates G-protein mechanism, causing local depolarization; GP at dendrites summates to AP
Gustation (Chemo): Salty, sour, sweet, bitter, umami stimuli trigger individual response in taste buds that have free nerve ending connections to CNs VII, IX, and X
Acoustic (mechano): Vibrations move basilar membrane with hair cells, causing mechanical opening of channels; K+ influx causes graded depolarization
Equilibrium: Certain positions, accelerations cause movement of otolithic membrane=mechanical opening of Ca2+ channels and depolarization
Vision: light hits pigment, second messenger activated, dark current stops, graded potential occurs
For each special sense:
the receptor organ which transduces the specific special sense stimulus
Sight: retina
Auditory: Organ of corti (in cochlear duct)
Olfaction: Olfactory epithelium
Taste: taste buds
Equilibrium: vestibular apparatus (contains utricle, saccule, and semicircular ducts)
Explain the neurologic pathway for transmission of the afferent impulse
Sight: 1. Retina (cones and rods) 2.optic nerve (sends visual info from retina to brain) 3.
optic chiasm (decussation-primary visual cortex can get info from both eyes; travels
along the optic tract to the thalamus) 4. Lateral geniculate nucleus in the thalamus
(visual info is organized before being sent to the primary cortex) 5. Visual cortex (info is
processed and perception occurs)
Auditory: 1. Cochlear branch 2. Vestibulocochlear nerve 3. Medulla oblongata 4. Midbrain (reflexes in colliculi) 5. Thalamus 6. Primary auditory cortex in temporal lobe (perception)
Olfaction: 1. Olfactory nerve (dendrites in conchae interact with oderants) 2. Olfactory tract 3. Hypothalamus 4. Amygdala 5. Olfactory cortex (no synapses at thalamus **only special sense that doesn't make a pit stop)
Taste: 1. Primary neurons extend from gustatory cells through CN VII and IX 2. Synapse in medulla oblongata 3. Secondary neurons take signals to thalamus 3. Tertiary neurons take signals to the primary gustatory cortex in insula of cerebrum
Equilibrium: 1. Stereocilia of maculae or crista ampullaris are distorted by motion 2. Nerve signal initiated through vestibular branch 3. Vestibulocochlear nerve 4. Medulla oblongata or cerebellum 5. Medulla will integrate info to reflexive eye movement and cerebellum will integrate it for skeletal muscle movement 6. Eventually will go to the thalamus and cerebral cortex for awareness (primary somatosensory cortex i think)
(c) and say which region of the cerebral cortex will "decode" the impulse for perception.
above
Explain the difference between transduction producing a graded potential, and which
cell/structure produces the eventual action potential that is transmitted into the CNS.
Sight: phototransduction requires a pigment to absorb photons of light. When the pigment is split, it activates a second messenger, causing cation channels to close. Hyperpolarization occurs within the receptor cell, causing it to stop releasing a NT that typically inhibits the bipolar cells. The bipolar cell can now release NT to the ganglion cell, which can propagate a signal to the brain
Auditory: Sound waves enter the EAM and vibrate the tympanic membrane, which moves auditory ossicles, which vibrates the oval window. Oval window vibration creates waves in the perilymph of the scala vestibuli that deform the vestibular membrane, causing waves in the endolymph, which vibrates the basilar membrane. Where the basilar membrane moves depends on frequency of waves (higher frequency = closer to oval window, then later transmitted to the more posterior side of primary auditory cortex). Hair cells on the basilar membrane have the tips of stereocilia embedded in the tectorial membrane, and when they move, the tip links connecting the stereocilia cause ion channels to open, allowing influx of potassium. The base of the hair cells can then release NT to a primary neuron, which creates graded potentials, then action potentials in the cochlear branch of CN VIII.
Olfaction: olfactory receptor cells have hairs that contain chemoreceptors in their plasma membrane. When an odorant stimulates an olfactory receptor cell, a G-activated protein sequence commences, opening Ca2+ and Na+ channels, causing a graded potential. This is transduction from chemical to electrical. These potentials summate to an action potential that is propagated down the olfactory receptor cell and a NT is released at the terminal end. The transducer can make an AP because it is the CN
Taste: Tastants (a molecule) bind to receptors in gustatory cells, causing a depolarization event that depends on the receptor cell. This is transduction. Could be G protein or ion channels. The event causes local potentials which eventually reach a primary neuron that is part of CN VII or IX.
Equilibrium: Similar to hearing; otolithic membrane moves with head movement, causing mechanical opening of ion channels on hair cells. Changes in polarization cause graded potentials that summate in vestibular branch
Understand the mode of stimulus for each sensation: photo, chemo, mechano-sense
Chemo: detect chemicals dissolved in fluid
Photo: detect changes in light intensity, color, and movement
Mechano-Sense: Detect physical deformation of the plasma membrane due to touch,
pressure, vibration, and stretch
List functions of both tissues which comprise the skeletal system: cartilage and bone.
Cartilage Functions: 1.) Support- confers form of function, is light (not mineralized)
2.) Flexibility -ribs need to be able to move etc
-compressible- rebound (acts as shock absorber)
3.) Decrease friction-low coefficient of friction
-decreases rubbing breakdown
Where does hyaline cartilage appear?
Joint surfaces (articular cartilage)
Where does Elastic cartilage appear?
Epiglottis and External Ear
Where does Fibrocartilage appear?
Vertebral discs and menisci (collagen confers resistance to stretch... more stretch =greater resistance)
All CT has: (3)
1.) Extracellular matrix
2.) Cells suspended in matrix
3.)Proteoglycan (protein backbone)
Osteoid
organic bone matrix secreted by osteoblasts
-made of collagen and ground substance w/proteoglycans and glycoproteins
-confers tensile strength
Ligaments
-Connect bone to bone
-dense regular CT
osteocyte
-a bone cell, formed when an osteoblast becomes embedded in the matrix it has secreted.
-not laying down osteocyte
-previously osteoblast
-acts as mechanoreceptor-sensitive to changes of rate of fluid movement through canaliculi- greater rate of fluid movement =greater corticoid mass
-regulatory cell type
Parthyroid Hormone
-increases blood calcium
-Humorally sensitive (Parathyroid gland)
-Calcium signal comes from the osteoclast for an endocrine response
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