Kristof physiology 2
Allodynia
Pain due to a stimulus that does not normally provoke pain
Function of C fibers (type IV fibers)
Pain fibers and autonomic postganglionic fibers
Analgesia
Pain relief
Main function of the vestibular system
Maintain balance
What is observed in the masseter reflex?
Masseter muscle is contracted, mouth is closed
List 8 proprioceptive reflexes
Masseter reflex, biceps reflex, triceps reflex, brachioradial reflex, brachioulnar reflex, abdominal muscle reflex, patellar reflex, achilles tendon reflex
On which side of the retinal is the temporal vision projected?
Medial
Where do the fibers in DCML decussate?
Medial lemniscus (brainstem)
In which case do you get a contraction both when you switch on and off the stimulus?
Medium stimulus intensity (both cathode make and anode break excitations)
Which part of the adrenal gland is innervated by the autonomic system?
Medulla
Definition of the equilibrium membrane potential
Membrane potential at which there is no net movement of a certain ion across the membrane
Role of hippocampus
Memory formation
Last menstruation and after
Menopause
Examples of utradian cycles
Menstruation cycle
Type of dye used in a vaginal smear
Methylene blue
In which case can goiter be present in euthyroidism?
Mild iodine deficiency, TSH overproduction
What is rheobase?
Minimum electrical current required to excite the nerve or muscle when the duration of the stimulus is indefinitely long
What is chronaxie?
Minimum time required to excite the nerve or muscle when twice the rheobase is applied
Other names for the proprioceptive reflex
Monosynaptic, myotatic, deep reflex
Characteristics of Cushing's syndrome
Moon face, buffalo hump, obese trunk/head/neck, thin extremities, DM, osteoporosis
Effect of eserine on the eye
More significant pupil constriction (more intense parasympathetic activation)
Length of smooth muscle AP
More than 300 ms
Functions of A-gamma fiber (type II fibers)
Motor fibers to muscle spindle
Functions of A-alpha fibers
Motor neurons (Ia) and primary endings of muscle spindle/ afferent/sensory fibers from proprioceptors (Ib)
Type of receptors on pupillary sphincter muscle
Muscarinic acetylcholine receptors
Cathode is closer to the muscle, circuit is closed, open conduction between the two poles, low stimulus is on. What is observed?
Muscle contraction
Cathode is closer to the muscle, circuit is closed, open conduction between the two poles, strong stimulus is on. What is observed?
Muscle contraction
Cathode is closer to the muscle, circuit is open, open conduction between the two poles, post middle stimulus excitation. What is observed?
Muscle contraction (anode break excitation)
Cathode is closer to the muscle, circuit is closed, open conduction between the two poles, middle stimulus is on. What is observed?
Muscle contraction (cathode make excitation)
Cathode closer to the muscle, closed circuit, no conduction between the two poles. What is observed?
Muscle contracts because there is a depolarization around the cathode
Symptoms of decerebration
Muscle rigidity, limbs in extension, back and neck in extension,
Symptoms of decortication
Muscle rigidity, upper limbs in flexion, lower limbs in extension, hyporeflexia, no communication, no locomotion, normal BP and respiration, no cortical reflexes
Which receptors are affected by curare?
Muscle type nicotinic acetylcholine receptors
Effect of atropine on the eye
Mydriasis (paralysis of the pupillary sphincter muscle, pupil dilation) Cycloplegia (paralysis of the ciliary muscles, no accomodation)
Movement of Na+, K+, and Cl- if membrane potential is between -85 mV and +55 mV
Na+: inflow K+: outflow Cl-: if under -60 outflow, if above -60 inflow
Movement of Na+, K+, and Cl- if membrane potential is 0 mV
Na+: inflow K+: outflow Cl-: inflow
Movement of Na+, K+, and Cl- if the membrane potential is +10 mV
Na+: inflow K+: outflow Cl-: inflow
Which visual field does not decussate?
Nasal visual field, projected on the temporal part of the retina
Polarity of cathode
Negative
Location of GLUT3
Neuron
In which patient group can the Babinski reflex be physiological?
Newborns
Which substance inhibits nicotinic ach receptors?
Nicotine
Type of receptors on ganglia
Nicotinic acetylcholine receptors
What kind of receptors are on the adrenal medulla?
Nicotinic acetylcholine receptors
What do the dopaminergic pathways from the substantia nigra to the striatum form?
Nigrostriatal dopaminergic system
What is observed in the mamillary reflex?
Nipple erection
Do PSPs have a threshold?
No
Anode is closer to the muscle, circuit is closed, open conduction between the two poles, strong stimulus is on. What is observed?
No contraction
Cathode is closer to the muscle, circuit is open, open conduction between the two poles, post strong stimulus. What is observed?
No contraction (AP elicited around the anode cannot pass through the negative charge accumulation around the cathode)
Cathode is closer to the muscle, circuit is open, open conduction between the two poles, post low stimulus excitation. What is observed?
No muscle contraction
What is observed in the crossed extensor reflex if the ipsilateral dorsal root is cut?
No reflex (no sensory input to initiate the reflex)
Can Post synaptic potentials (PSPs) be inhibited by TTX, why?
No, they do not use fast voltage gated Na+ channels.
Other name for DM2
Non-insulin dependent diabetes mellitus
What kind of hormone is the hPL?
Nonapeptide
Which enzymes are required for the synthesis of androgens/sex hormones from progesterone?
None
Effect of increased stimulus intensity on the amplitude of the contraction curve, above maximum threshold
None, all fibers have reached their threshold
What is observed in the crossed extensor reflex if the contralateral dorsal root is cut?
Normal reflex, ipsilateral flexion and contralateral extension
What can be seen in a proestrus phase?
Nucleated epithelial cells
Typical body shape for DM2 patients
Obese/overweight
Result of ventromedial hypothalamus
Obesity (no feeling of satiety)
What are hair cells made of?
One kinocilium and multiple smaller stereocilia
How is reflex time measured in a decapitated frog?
One leg is put into acetic acid and the reflex time is measured
What is the dominant cell type in the diestrus/anestrus?
Only a few cells are present, mainly leukocytes
What is observed in the crossed extensor reflex if the ipsilateral ventral root is cut?
Only contralateral extension
What is observed in the crossed extensor reflex if the contralateral ventral root is cut?
Only ipsilateral flexion
What causes the depolarization in the AP?
Opening of fast voltage gated Na+ channels causes Na+ influx
What causes repolarization in the AP?
Opening of voltage gated K+ channels causes K+ outflow
What is tested in the corneal reflex?
Ophthalmic nerve (afferent) and facial nerve (efferent)
Which is the most important pathway from the optic tract?
Optic tract-lateral geniculate body-optic radiation-primary visual cortex
Oroxigenic molecules
Orexin, ghrelin, insulin
Where is linear acceleration detected?
Otolith organs
Typical onset of DM2
Over 40 years old
Which hormones are produced by the hypothalamus?
Oxytocin, TRH, CRH, GnRH, GHRH, ADH
What stimulates calcitriol?
PTH
Parasympathetic or sympathetic fibers are longer, and why?
Parasympathetic, because the ganglia are located on the viscera and not close to the spinal cord
What is eserine?
Parasympathomimetic agent, it inhibits acetylcholine esterase (no breakdown of acetylcholine)
Types of sympathetic ganglia
Paravertebral (sympathetic trunk) and prevertebral
Which disease presents if the nigrostriatal dopaminergic system does not work properly?
Parkinson's disease (low dopamine levels)
What is the Babinski reflex?
Pathological response to the plantar reflex, dorsal flexion
Pupil/light reflex pathway
Photoreceptors in the retina-bipolar cell-ganglion cell-optic nerve-optic chiasm-optic tract-pretectal region-Edinger Westphal nucleus-parasympathetic preganglionic fibers-ciliary ganglion-parasympathetic postganglionic fibers- pupillary sphincter muscle-miosis (pupillary constriction)
What factors increases the formation of GH?
Physical exercise, sleeping, and low blood glucose levels
Decreased levels og GH in childhood
Pituitary dwarfism
What can bitemporal hemianopia be a sign of?
Pituitary gland tumor
What is observed in the achilles tendon reflex?
Plantar flexion
What is observed in the plantar reflex?
Plantar flexion
Characteristics of experimental setup for each of the polar excitement, Pflüger's law, and electrotonus examinations
Polar excitement: one stimulator, conduction between poles is blocked via NH4+ Pflügers law: one stimulator, free conduction between poles Electrotonus: two stimulators, free conduction between poles
Anode is closer to the muscle, circuit has just been opened, no conduction between the two poles. What is observed?
Polarities switch. There is a depolarization (accumulation of positive ions) around the anode, a contraction is observed.
Other names for exteroceptive reflex
Polysynaptic, skin, surface reflex
Symptoms of hyperglycemia
Polyuria, polydipsia, polyphagia, itchy skin
Which center is tested in the masseteric reflex?
Pons
Via what does GHRH reach the pituitary gland?
Portal vessels
Polarity of anode
Positive
Where do the two somatosensory systems terminate?
Postcentral gyrus
Where is the heating center located?
Posterior hypothalamus
Types of implicit memory
Procedural, priming, classical conditioning/pavlovian, non-associative
Which hormone increases after ovulation?
Progesterone
Steps of synthesis of corticosterone from progesterone
Progesterone -> 11-desoxyxorticosterone -> corticosterone
Which hormones increase towards the end of the pregnancy?
Progesterone, estradiol, hPL (human placenta lactogen)
Which hormone in the anterior pituitary is not affected if the portal circulation is blocked?
Prolactin
Two uterine phases
Proliferative and secretory
which phase in humans does the proestrus correspond to?
Proliferative phase (uterus), follicular phase (ovaries)
What causes iatrogenic Cushing's?
Prolonged glucocorticoid therapy
What are the two types of reflexes?
Proprioceptive and exteroceptive
In which form are thyroid hormones mostly found in?
Protein bound (thyroxin binding globulin)
Functions of A-delta fibers (type III fibers)
Protopathic sensation
Type of sensation carried by the spinothalamic system
Protopathic: pain, temperature, crude touch
Which factors can activate the stress-axis?
Psychological stress Physical stress: extreme exercise, pain, hypoglycemia
Where does the pyramidal tract cross?
Pyramidal decussation (medulla)
What can the babinski reflex indicate?
Pyramidal tract lesion
Origin of the descending monoaminergic system
Raphe nucleus of the brain
What are TRVP-1 receptors?
Receptors found mainly in the nociceptive neurons (such as free nerve endings). They are involved in the transmission of pain (nociception)
Function of EEG
Recording the electrical activity of the brain
Location of GLUT 1
Red blood cells and blood brain barrier
Deuter anomaly
Reduced pigment in green cones
Protanomoly
Reduced pigment in red cones
Tritanomaly
Reduced pigment in the blue cones
function of cerebellum
Regulation of movements, motor coordination, and muscle tone regulation
Effect of TSH on thyroid gland
Release of T3 (tri-iodo-thyronine) and T4 (tetra-iodo-thyronine/thyroxin)
Effect of TRH on the anterior pituitary
Release of TSH
Example of semantic memory
Remembering facts
Symptoms of Parkinson's disease
Resting tremor, rigidity, bradykinesia, hypokinesia, akinesia, micrography, postural instability, increased salivation, poor facial expressions
Layers of the eyeball
Retina, choroidea, sclera
What does rhodopsin consist of?
Retinal and opsin
Characteristics of endolymph
Rich in K+ (similar to intracellular fluid)
Characteristic of perilymph
Rich in Na+ (similar to extracellular fluid)
In the tonic neck reflexes, what does turning the head to the right result in?
Right side extension of the limbs and left side flexion of the limbs
There is a lesion in the left optic tract, which vision is affected?
Right temporal vision, left nasal vision (homonymous hemianopia)
If the fast component is rightwards and the slow one is leftwards, which is the direction of the nystagmus?
Rightwards
Which receptors are affected by vitamin A deficiency?
Rods
Which type of photoreceptors are important for scotopic vision?
Rods
What is tested in the plantar reflex?
S1-S2
Which segments are tested in the achilles tendon reflex?
S1-S2
What is tested in the anal sphincter?
S4-S5 segments
Which structures in the cochlea are filled with endolymph?
Scala media
Which structures in the cochlea are filled with perilymph?
Scala tympani and scala vestibuli
Why do levels of progesterone increase in the luteal phase?
Secreted by corpus luteum which grows in the luteal phase
Which phases in humans does the metestrus and diestrus correspond to?
Secretory phase/luteal phase
Where is angular acceleration detected?
Semicircular canal
What are the two components of the vestibular apparatus?
Semicircular canals and otolith organs
Neurotransmitter of the descending monoaminergic pathway
Serotonin
Symptoms of low decerebration
Sherringtonian reflexes (tonic labirynthine and neck reflexes) can be evoked, no righting reflex (postural reflex), no locomotion, hyperactive proprioceptive reflex
Symptoms of high decerebration
Sherringtonian reflexes and righting reflexes can be evoked, locomotion may be evoked upon painful stimulus
Other name for myopia
Short sighted
Loctation of peripheral thermoreceptors
Skin, liver, and skeletal muscle
Typical body shape in individuals with DM1
Skinny, the cells of the body are not getting any glucose
What happens if you wake up in REM phase?
Sleep paralysis
Effect of increased corticsol on CNS
Sleepiness, depression
When are theta waves normal?
Sleeping adults, children anytime
What are the indications for an EEG examination?
Sleeping disorder, epilepsy, brain death
What causes hyperpolarization at the end of the neuron AP?
Slow closure of the K+ channels
Components of nystagmus
Slow component and fast component
Two main phases of the sleep cycle
Slow wave sleep and REM phase
Where do the fibers in the spinothalamic tract decussate?
Spinal cord, same level of corresponding DRG
Via which pathway are the signals from the peripheral receptors carried?
Spinothalamic pathway
Which structures in the basal ganglia can be inhibited by the striatum?
Substantia nigra, pallidum (pars interna and externa)
Where can information from the optic tract go?
Superior colliculus, pretectal region, lateral geniculate body
Which hypothalamic nuclei produce oxytocin and ADH?
Supraoptic and paraventricular nuclei
What is tested in the mamillary reflex?
T4 segment
What is tested in the superficial abdominal reflex?
T7-T11 segments
Which segments are tested in the abdominal reflex?
T8-T12
Which hormones are present in a bigger concentration in the portal circulation than in the peripheral circulation?
TRH
In which case can goiter be present in hyperthyroidism?
TSH producing tumor, autoimmune disease (antibodies stimulate TSH release)
Which hormones are produced in the anterior pituitary?
TSH, ACTH, LH, FSH, GH, prolactin
Effect of LH on testis, and via which cells
Targets Leydig cells and increases production of testosterone
Effect of FSH on testis, and via which cells
Targets Sertoli cells, increases spermatogenesis and inhibin production
What does the equilibrium potential depend on (Nernst equation)?
Temperature, ion charge, intracellular and extracellular concentrations
Which visual field decussates?
Temporal visual fiels, projected on the nasal part of the retina
How would the shape of the compound AP change when the recording electrodes are moved further away?
The AP becomes wider
How does the amplitude of the contraction curve change when the intensity of the stimulus is increased (from above threshold to higher), and why?
The amplitude is increased, more fibers are activated (each fiber has a different threshold). This is called a compound stimulus, where the APs of individual fibers are summated
How is the amplitude of the PSP different compared to the amplitude of the AP?
The amplitude of the AP is constant while that of the PSP decreases with time and distance
Effect of higher acetic acid concentration on reflex time
The higher the concentration, the shorter the reflex time
Relation between excitability and diameter of nerve fibers
The larger the diameter, the higher the excitability (lower threshold)
Cathode is closer to the muscle, circuit has just been opened, no conduction between the two poles. What is observed?
The polarities of the cathode and anode will switch. There will be a hyperpolarization (accumulation of negative charge) around the cathode, no contraction is elicited.
Why does 11-beta-hydroxylase deficiency cause non-salt losing form of androgenital-syndrome?
The production of 11-desoxycorticosterone and corticosterone is not inhibited since 21-beta-hydroxylase is present. 11-desoxycorticosterone and corticosterone have a sreduced but similar effect as aldosterone
What generates the electrical activity of the brain?
The pyramidal cells in the 5th cortical layer are the main generators of post synaptic potentials. The depolarization (EPSP) or hyperpolarization (IPSP) will cause an electrical difference between the cortical layers which forms an electrical current that can be measured by an EEG
Why do the levels of FSH regress during the follicular phase?
The rise in estrogen inhibits FSH secretion
How is the mechanical stimulus from sound waves transformed into an electrical signal?
The sound waves result in movement of the endolymph. The movement of the endolymph results in the movement of the stereocilia towards the kinocilium. This causes opening of the mechanosensitive potassium channels, resulting in K+ influx (endolymph is rich in K+). The inflow of K+ causes depolarization and opening of the voltage gated calcium channels. This results in the influx of calcium and the release of neurotransmitters (glutamate/excitatory). Glutamate binds to the NMDA-R receptors on the sensory neuron which causes opening of the ligand gated Na+ channels. The inflow of sodium to the sensory neuron causes a depolarization and the signal is transported.
What forms the EEG wave?
The summation of about 1 million PSPs
What is the Bell-Magendie law?
The ventral root is the motor root, posterior root is the sensory root
Anode is closer to the muscle, closed circuit, no conduction between the two poles. What is observed?
There is a hyperpolarization around the anode (accumulation of negative ions), no contraction is elicited
Why is there no anode break excitation with a strong stimulus, cathode closer to the muscle?
There is a large accumulation of negative charge around the cathode, blocking the AP which was elicited around the anode from reaching the muscle
What is the cathode make excitation?
There is an accumulation of positive charge around the cathode, causing depolarization and increase in excitability. It is easier to elicit a contraction, lower threshold
Three types of physiological nystagmus
Thermal nystagmus, optokinetic nystagmus, postrotational nystagmus
Why are calcium channels important for signal transmission?
They cause exocytocis of the vesicles with neurotransmitters into the synapse where they can bind to the posynaptic membrane
Why do PSPs not have a refractory period?
They do not depend on fast voltage gated Na+ channels; no inactivation gate
How do glucocorticoids cause high blood pressure?
They increase the sensistivity of adrenergic receptors and increase water and salt retention
Which parts does proinsulin consist of?
Three amino acid chains: A, B and C. The C chain conects the A and B chains
Which reflexes can be evoked in decerebration (both types)?
Tonic labyrinthine reflex and tonic reflesxes
Function of the ossicles
Transmition and amplification of sound
Which cells release hCG?
Trophoblast cells
Way of action of dopamine on prolactin
Tuberoinfundibular dopaminergic system
Which parts does insulin consist of?
Two amino acid chains: A and B chain
Difference between type one and two Addison's disease
Type one causes hyperpigmentation, not the secondary type
Type of feedback by which TRH acts on itself
Ultrashort negative feedback
Characteristics of petit mal seizure
Unconsciousness, absence (zoning out)
Which frequency is the infrasound?
Under 20 Hz
Two types of leads in EEG
Unipolar and bipolar
Characteristics of grand mal seizure
Unvoluntary movements, unconcsiousness, shaking
In the tonic neck reflexes, what does lifting the head up result in?
Upper limbs are extended and lower limbs flexed
Effect of ADH on V1, V2, and V1-b receptors
V1: vasodilation V1-b: release of adrenocorticotrope hormone (ACTH) from the anterior pituitary V2: collecting tubules, water retention
How does the posterior hypothalamus decrease the temperature?
Vasoconstriction, decreases sweating, shivering, change in behaviour
How does the anterior hypothalamus cool the body?
Vasodilation in the periphery, sweating, change in behaviour (undressing, seeking shade)
Location of glucose receptor neurons
Ventromedial hypothalamus
What is examined in the compass reflex?
Vestibular system
What is examined in the turning reflex?
Vestibular system
How does adrenaline increase blood glucose levels?
Via beta 2 receptors in the liver, it stimulates the breakdown of glycogen. Via alpha receptors on beta cells, it inhibits the production and secretion of insulin.
Why do glucocorticoids cuase decreased calcium content in bones?
Via inhibition of osteoblasts
How does GnRH reach the anterior pituitary gland?
Via portal vessels
How does TRH reach the anterior pituitary gland?
Via portal vessels
Which vision do patients with presbyopia struggle with?
Vision of objects close to the eye
What is iconic memory?
Visual memory
Which vitamin is important for rhodopsin?
Vitamin A
Which vitamin is required for the production of steroid hormones from cholesterol?
Vitamin C
Other names for calcitriol
Vitamin D and 1,25 dihydroxycholecalciferol
where are the fast voltage gated sodium channels found in the neuron?
nodes of ranvier and axon hillock
Neurotransmitter released by sympathetic postganglionic fibers
norepinephrine
Where is calcitonin produced?
parafollicular cells of the thyroid gland (c-cells)
What kind of hormone is glucagon?
peptide hormone
When do gamma waves occur?
When focusing
How is the convexity of the lens changed?
When the ciliary muscles contract, the zonular fibers relax and the lens becomes more loose. The looser the lens is, the more of a convex shape it will hold.
Strabismic ambylopia
When the eyes are not alligned, the brain turns off the visual input from one of the eyes (to avoid getting
Which reflexes can be investigated in a decapitated frog?
Wiping reflex, reflex time, embracing refles, Brondgest phenomenon
What causes prebyopia?
With age, the lens becomes more rigid and issues arise with the accomodation
Which scenario can provoke beta waves?
Writing a test
Which chromosome is color vision linked to?
X chromosome
Duration of long term memory
Years
What is the inner layer of the adrenal cortex?
Zona reticularis
Optokinetic nystagmus
a reflexive eye movement in which the eyes will involuntarily track a continually moving object
Function of alpha cells
produce glucagon
Four phases of estrous cycle
proestrus, estrus, metestrus, diestrus
blood glucose in diabetes mellitus
above 7 mmol/L
Neurotransmitter released by preganglionic neurons
acetylcholine
Where are glucocorticoids produced?
adrenal cortex
Where is epinephrine produced?
adrenal medulla
Where is glucagon produced?
alpha cells of pancreas
What is long-term potentiation (LTP)?
an increase in a cell's firing potential after brief, rapid stimulation. Believed to be a neural basis for learning and memory
Impaired fasting glucose (IFG)
an intermediate stage between normal glucose homeostasis and diabetes.
Hemiballism
an involuntary and violent movement of a large body part
Where is the aqueous humor located?
anterior chamber (between cornea and lens)
Where is growth hormone produced?
anterior pituitary gland
Where are the hair cells in the cochlea located?
basilar membrane
where is insulin produced?
beta cells of pancreas
effect of TTX (tetradotoxin)
blocks fast voltage gated sodium channels
effect of TEA (tetra ethyl ammonium)
blocks voltage gated potassium channels
How does glucagon increase blood glucose?
breaks down glycogen and stimulates gluconeogenesis
What is myosis?
pupil constriction
effect of inhibitory synapse on the post synaptic membrane
chloride and potassium channels open causing outflow of potassium and inflow of chloride, resulting in a hyperpolarization of the post synaptic membrane (making it harder to elicit an AP)
What kind of cells are in the adrenal medulla?
chromaffin cells which produce catecholamines (adrenaline, noradrenaline and dopamine)
What is myxedema?
condition caused by hypothyroidism where proteoglycans escape into the interstitial fluid and cause fluid retention (osmotically active)
Strabism
cross-eyed
How is astigmatism corrected?
cylindrical lens
Hypoalgesia
decreased pain sensation
Where is somatostatin produced?
delta cells of pancreas
Function of inner hair cells
detect sound
What is mydriasis?
pupil dilation
What inhibits prolactin?
dopamine
What is goiter?
enlargement of the thyroid gland
types of explicit memory
episodic and semantic
Types of long term memory
explicit (declarative) and implicit (non-declarative)
Where does fertilization take place?
fallopian tubes
Example of episodic memory
first day of school
Two ovarian phases
follicular and luteal
what is GIP?
gastric inhibitory peptide, or glucose dependent insulinotrop peptide. It is secreted by the proximal part of the small intestine and inhibits gastric juice secretion and stimulates insulin production (promotes digestion).
which hormones increase blood glucose?
glucagon, adrenaline, noradrenaline, glucocorticoids (cortisol), growth hormone, thyroid hormones, and somatostatin
What does the zona fasciculata secrete?
glucocorticoids (cortisol) and androgens
which substances stimulate beta cells?
glucose, some amino acids, glucagon, parasympathetic nervous system (Ach), incretins (GIP, GLP-1)
Which neurotransmitters are found in the excitatory synapse?
glutamate and aspartate
What type of hormone is hCG?
glycoprotein hormone
types of nonassociative learning
habituation and sensitization
What is the organ of Corti composed of?
hair cells and supporting cells forming neuroepithelium
What connects the scala tympani to the scala vestibuli?
helicotrema
Auditory agnosia
inability to recognize sounds
Hyperalgesia
increased pain sensation
function of aldosterone
increases Na+ reabsorption, K+ and H+ secretion
What is the end plate potential?
initial depolarization of motor end plate
which hormones decrease blood glucose?
insulin
What causes goiter?
iodine deficiency
Photopigment in cones
iodopsin
NMDA-R
ionotropic receptor for glutamate when bound, becomes permeable to cations (Na/Ca)
role of somatostatin in blood glucose regulation
it raises blood glucose and inhibits beta cells in the pancreas
Ataxia
lack of muscle coordination
Where is the hunger center located?
lateral hypothalamus
amblyopia
lazy eye
range of blood glucose in hypoglycemia
less than 3.5 mmol/L
normal OGTT
less than 7.8 mmol/l
Duration of sensory memory
less than a second
Sensory aphasia
loss of ability to understand language
Anesthesia
loss of sensation
what are the characteristics of GLUT2?
low affinity and high capacity for glucose
Effect of calcitonin of blood calcium
lowers blood calcium
1st menstruation
menarche
What is the adrenal medulla?
modified sympathetic ganglion
which blood glucose values in an OGTT are indicative of diabetes mellitus?
more than 11 mmol/l
Location of GLUT4
muscle and adipose tissue
Protonopia
red color blindness, no red cones
Types of cones
red, green, blue
When do alpha waves occur?
restful waking state (such as meditation)
Photopigment in rods
rhodopsin
Example of procedural memory
riding a bike
type of axonal conduction of AP
saltatory
Duration of short term memory
seconds to minutes
Location of GLUT5
small intestine
why do GLUT2 have low affinity for glucose?
so that glucose is only taken in when it is abundant in the blood, not when its scarce and needed for energy production
why do GLUT2 have high capacity for glucose?
so that high amount of glucose can be taken up and more insulin synthesised to regulated the blood glucose
effect of excitatory synapse on the post synaptic membrane
sodium and calcium channels open, causing inflow of sodium and calcium and depolarization of the post synaptic membrane
What is the resting membrane potential maintained by?
sodium potassium ATPase
which molecules inhibit beta cells?
somatostatin, adrenaline, and noradrenaline via alpha receptors.
Where is Norepinephrine produced?
sympathetic postganglionic fibers
how are beta cells stimulated? what is the result?
they are stimulated by glucose via GLUT2 and result in the production of insulin.
Where is iodine stored?
thyroid gland
What is TRH and what does it do?
thyrotropin releasing hormone, it stimulates prolactin
where are voltage gated potassium channels found in the neuron?
under the myelin sheath
Capacity of long term memory
unlimited
What are the two otolith organs?
utricle and saccule
Where is the satiety center located?
ventromedial hypothalamus
What is the middle layer of the adrenal cortex?
zona fasciculata
equilibrium membrane potential for Na+
+55 mV
Organs involved in the stress axis and their corresponding products
- Hypothalamus: corticotropin releasing hormone (CRH) - Anterior pituitary: adrenocorticotropic hormone (ACTH) - Adrenal cortex: cortisol(glucocorticoid)
Functions of GH
- growth processes - anabolic hormone; increases protein synthesis and increases muscle mass - increases blood glucose by decreaseing glucose uptake by cells - increases lipolysis
Range of membrane potential in which both the activation and inactivation gates of the fast voltage gated sodium channels are open
-20 to -40 mV
Membrane potential at which the inactivation gate of the voltage gated sodium channels is closed (also MP at which potassium channels open; peak of AP)
-30 mV
Equilibrium membrane potential for Cl-
-60 mV
Equilibrium membrane potential for K+
-85 mV
Reasons for a false positive pregnancy test with the immunological method
In males: testicular cancer In females: abnormally high FSH and LH levels caused by menopause, choliocarcinoma, wilms tumor, hydratidiform mole
where are the voltage dependent calcium channels found on the neuron?
In the axon terminal
Where are parasympathetic ganglia located?
In the wall of the innervated organ (intramural)
How do glucocorticoids increase blood glucose?
Increase gluconeogenesis and decrease glucose uptake
How does T3 and T4 increase blood glucose?
Increase glucose absorption from the small intestine
Functions of glucocorticoids (cortisol)
Increase of blood sugar via increasing gluconeogenesis, increasing glycogen synthesis, decreased glucose uptake of cells, increased proteolysis, amino acid release from skeletal muscle, lipolysis in limbs (central shift of adipose tissue), surfactant production by type II pneumocytes, increased sensitivity of adrenergic receptors, decreased calcium in bones, increased sensitivity of mineralocorticoid receptors (water and salt retention), inmmunosuppressiv effect, decreased WBC, decreased interleukin levels, decreased C-reactive protein levels
What is cathelectrotonus?
Increase of excitability around the cathode due to the accumulation of positive charge (depolarization)
Effect of amino acids on glucagon secretion
Increased
Effect of anelectrotonus on the threshold
Increased
Effect of catecholamins of glucagon secretion
Increased
Effect of glucose on glucose receptor neurons
Increased activity (after eating, BS increases, activity of glucose receptor neurons increases, ventromedial hypothalamus is activated-satiety)
Effect of gestational diabetes on chance of developing DM2
Increased by 50%
Effect of Cushing syndrome
Increased cortisol levels
Effect of oroxigenic molecules
Increased food intake
Why does hyperthyroidism cause exophthalamus?
Increased proliferation of retrobulbar tissue
Effect of glucocorticoids on glucagon
Increased secretion
Effect of growth hormone on glucagon
Increased secretion
Causes of increased pain sensation (hyperalgesia or allodynia)
Increased sensitivity of nociceptors, inflammation
Effect of acidosis on concentration of free calcium
Increased, plasma proteins bind H+
Effect of glucagon on blood glucose
Increases
Effect of testosterone on spermatogenesis
Increases
Effect of PTH on calcium levels on blood calcium
Increases blood calcium
Effect of calcitriol on blood calcium
Increases blood calcium
How does GH increase blood glucose?
Increases glucose levels and decreases glucose uptake by the cells
How does adrenaline and noradrenaline increase blood glucose?
Increases glycogen break down in the liver via beta-2 receptors
Functions of TSH
Increases iodine uptake to thyroid gland Increases size of thyroid gland Increases all enzymes involved in T3 and T4 formation Increases thyroglobulin formation
Function of testosterone in females
Increases libido
Effect of kisspeptines
Inhibit GnRH during lactation
Effect of ACTH on CRH
Inhibition
Effect of T3 on TSH
Inhibition
Effect of TSH on TRH
Inhibition
Effect of cortisol on ACTH
Inhibition
Effect of cortisol on CRH
Inhibition
Effect of dopamine on prolactin
Inhibition
Effect of estradiol on LH (not the end of follicular phase)?
Inhibition
Effect of insulin on hormone sensitive lipase
Inhibition
Effect of insulin on lipolysis
Inhibition
Effect of insulin, somatostatin, and glucose on glucagon secretion
Inhibition
Effect of magnesium on NMDA-R
Inhibition
Effect of testosterone on LH and GnRH
Inhibition
Final outcome of the indirect loop on the thalmaus
Inhibition
Effect of LH and FSH on GnRH
Inhibition (negative feedback)
Types of post synaptic potentials
Inhibitory and excitatory
What kind of fibers does the substantia nigra receive from the striatum?
Inhibitory fibers (GABA)
What kind of fibers does the thalamus receive from the substantia nigra?
Inhibitory fibers (GABA)
What kind of interneuron is the Renshaw cell?
Inhibitory neuron
Effect of inhibin
Inhibits secretion of FSH and GnRH
Effect of progesterone on hypothalamus and anterior pituitary gland
Inhibits secretion of GnRH, LH, and FSH
Effect of increased sensitivity of adrenergic receptors
-Beta-1 receptors in the heart: increased HR, SV, CO, BP -alpha-1 receptors in the vessels: increased TPR and BP
Causes of hemiballism
Injury of subthalamic nucleus, pathways between subthalamic nucleus and globus pallidus
Which factors activate adrenocorticotropic hormone?
-CRH (hypothalamus) -catecholamines (adrenaline, noradrenaline) -ADH/vasopressin (via V1-b receptors)
Causes of secondary Addison's disease
-CRH deficiency -> low ACTH -> low cortisol -ACTH deficiency -> low cortisol
Reasons for secondary Cushing syndrome
-CRH overproduction -> increased ATCH -> high cortisol -ACTH overproduction -> high cortisol
Effect of FSH and LH on ovaries
-Production of estradiol by theca interna cells and granulosa cells -Production of progesterone by corpus luteum
In which cases can postganglionic sympathetic fibers secrete acetylcholine
Innervation of sweat glands
Effect of hyperparathyroidism on urine
-decreased calcium concentration -increased phosphate concentration
Characteristics of gamma waves
-high frequency -small amplitude -short duration
Endocrine causes of hyperglycemia
-hyperthyroidism -giantism (GH, childhood) -acromegaly (GH, adult) -glucagonoma (glucagon producing tumor) -cushing-syndrome (cortisol overproduction) -pheocromocytoma (adrenal medulla tumor) -somatostatinoma
Function of descending monoaminergic system
It inhibits pain transmission at the level of the spinal cord with serotonin
How does PTH decrease plasma phosphate?
It inhibits the Na+/PO4 2- cotransportes in the proximal convoluted tubule
Why is color blindness more frequent in males?
It is linked to X chromosomes
Why can high levels of LH give a false positive hCG test?
LH and hCG have the same beta subunit, they have very similar structures
Other examples of glycoprotein hormone
LH, FSH, TSH (released by anterior pituitary)
glycoprotein hormones
LH, FSH, TSH, hCG
What is diabetes mellitus type 1 caused by?
Lack of insulin, viral infection, autoimmune disease where antibodies are produced against beta cells of the pancreas
Decreased levels IGF-1 in childhood
Laron's dwarfism
Effect of pheochromocytoma (adrenal medulla tumor)
-increased BP -hyperglycemia -mydriasis (pupil dilation) -piloerection -increased HR, BP, SV, CO, TPR -decreased blood flow to GI, urogenital tract, and skin -increased blood flow to skeletal muscle and coronary aa -decreased gastric motility and secretion of gastric juice -sphincter contriction -uterus and urinary bladder relaxation
On which side of the retina is the nasal vision projected?
Lateral
Where are glucose sensitive neurons located?
Lateral hypothalamus
In the tonic neck reflexes, what does turning the head to the left result in?
Left side of extension of the limbs and right side flexion of the limbs
There is a lesion in the right optic tract, which vision is affected?
Left temporal vision, right nasal vision (homonymous hemianopia)
Anorexigenic molecules
Leptin and CCK
What causes hemiballism?
Lesion of the subthalamic nucleus or the pathways between the subthalamic nucleus and the pallidum
Duration of AP in neuron
Less than 4 ms
What is the dominant cell type in the metaestrus?
Leukocytes
What type of receptors are on the post synaptic membrane?
Ligand gated ion channels
Issue in hypermettropia
Light rays are focused behind the retina, the refractive power is too weak
Issue in myopia
Light rays are focused in front of the retina, the refractive power is too strong
Visual pathway
Light-photoreceptors-bipolar cell-ganglion cell-optic nerve-optic chiasma-optic tract
Which part of the body has the finest two point discrimnation?
Lip
Acute stress reactions
-increased blood glucose via B2-receptors on the liver -increased FFA via B3 receptors in adipose tissue -pupil dilation via A1 receptors on dilator pupil m. -piloerection via A1 receptors on erector pili -increased HR, SV, CO, BP via B1-receptors in the heart -increased TPR via A1-receptors on vessels (vasoconstriction) -decreased blood flow to GI, urogenital tract, skin via A1-receptors -increased blood flow to skeletal muscle and coronary aa via B2-receptors -decreased gastric motility and gastric juice production -sphincter constriction via A receptors -uterus and urinary bladder relaxation via B2-receptors
Effect of hyperparathyroidism on plasma
-increased calcium concentration -decreased phosphate concentration
Effect of insulin on skeletal muscle
-increased glucose uptake via GLUT4 -increased glycogen synthesis -increased protein synthesis -increased amino acid uptake -decreased proteolysis -decreased amino acid release -increased potassium uptake
Effect of insulin on adipose tissue
-increased glucose uptake via GLUT4 -increased lipid synthesis -increased lipid uptake via stimulation of lipoprotein lipase -decreased lipolysis via inhibition of the hormone sensitive lipase -decreased free fatty acid release -decreased ketone body formation
Functions of glucagon
-increased glycogenolysis -increased gluconeogenesis -glucose release from the liver -increased proteolysis -amino acid release from skeletal muscle -increased lipolysis
How does calcitriol increase blooc calcium?
-increases calcium ansorption from the GI -increases calcium reabsorption in the kidneys
Effect of PTH
-increases calcium reabsorption in the distal convoluted tubule -increases osteoclast activity -decreases concentration of plasma phosphate
Effect of prolactin
-milk production -surfactant production -stimulates kisspeptines
Function of testosterone in males
-promotion of spermatogenesis -increases protein synthesis (anabolic steroid hormone) -responsible for primary and secondary male features
Function of oxytocin
-uterine contraction -milk ejection -orgasm -prosocial hormone -pair bonding -maternal behavior
Threshold for the human ear (in decibel)
0 dB
What is the standard sound pressure?
0 dB or 20 uPa
Frequency of delta waves
0-4 Hz
how is an oral glucose tolerance test performed?
1 g/bwkg is dissolved in 300 ml of water and consumed within 10 minutes. The blood glucose is measured 2 hours later
Conduction velocity of C fibers
1 m/s
Diameter of C fibers
1 micron
Extracellular concentration of free calcium ions
1,1-1,4 mmol/l
Effect of insulin on liver (enough glucose)
1- increased glycogen synthesis 2- decreased glycogenolysis 3- decreased gluconeogenesis 4- increased lipid formation from glucose (lipogenesis) 5- increased glycolysis 6- decreased ketone body formation
How long is the refractory period in a neuron?
1-2 ms
Length of neuron AP
1-2 ms (less than 4 ms)
Typical onset of DM1
10-24 years old
If you double the sound decibel, by how much does the frequency increase?
100 times
Enzyme required for synthesis of aldosterone from corticosterone
11-beta hydroxylase
What is the molecular mechanism elicited by light in the photoreceptors?
11-cis-retinal —> trans-retinal
Conduction velocity of A-delta neurons
12-30 m/s
Frequency of beta waves
13-30 Hz
Diameter of A-alpha fibers
15 microns
Conduction velocity of A-gamma neurons
15-30 m/s
Which enzymes are present in the zona fasicularis and reticularis?
17-alpha-hydroxylase
Which enzyme in the glomerular zone of the glomerular zone of the adrenal cortex is responsible for the production of aldosterone?
18-aldehyde oxygenase enzyme
The ratio of inner to outer hair cells in the human cochlea is approximately
1:3
What are the 4 stages of slow wave sleep and their characteristics?
1st stage: alpha waves (restful waking state) disappear and are replaced with theta waves (light sleep) 2nd stage 3rd stage: delta waves appear (synchronized, low frequency, high amplitude) 4th stage: delta waves (synchronized, low frequency, high amplitude)
Total concentration of extracellular calcium
2,2-2,8 mmol/l
How many pascals is 0 dB?
20 micropascal
Formula for sound pressure level in dB
20 x log10( given sound pressure/standard sound pressure)
How much of the sleep cycle does the REM phase in adults occupy?
20%
Range of frequencies that can e detected by the human ear
20-20 000 Hz
Length of AP in pacemaker cells
200-300 ms
Causes of androgenital syndrome/virilism (androgen overproduction)?
21-beta-hydroxilase deficiency, 11-beta-hydroxilase deficiency, androgen producing tumor, hyperactivation of reticular zone
Enzyme required for synthesis of corticosterone from progesterone
21-beta-hydroxylase
Which enzymes are required for the synthesis of glucocorticoids (cortisol) from progesterone?
21-beta-hydroxylase and 11-beta-hydroxylase
Enzymes required for the synthesis of aldosterone from progesterone
21-beta-hydroxylase, 11-beta-hydroxylase
Refractive power of the lens
23 diopters
Diurnal cycle
24 hour cycle
How long is the normal female cycle?
28 days
How can a petit mal seizure be recognized on an EEG?
3 Hz spike wave (3 spike waves in 1 second)
Diameter of A-delta fibers
3 microns
Diameter of B fibers
3 microns
Conduction velocity of B fibers
3-15 m/s
Above which undetected threshold is there a hearing deficit?
30 dB
Frequency of gamma waves
30-100 Hz
Conduction velocity of A-beta neurons
30-70 m/s
How long is the longitudinal section of the cochlea?
33 mm
How long is the rat cycle?
4-5 days
normal fasting blood glucose
4-5.5 mmol/L
Average weight of fetus in pregnancy with gestational diabetes
4-6 kg
Length of AP in skeletal muscle
4-6 ms
Frequency of theta waves
4-8 Hz
Refractive power of the cornea
42 diopters
Diameter of A-gamma fibers
5 microns
When does implantation take place?
5-6 days after fertilization
How much of the sleep phase in newborns does the REM phase occupy?
50-60%
how many amino acids does insulin have?
51
range of blood glucose in IFG
6-7 mmol/L
Total refractive power of the eye
65 diopters
Capacity of short term memory
7 +/- 2 items
impaired glucose tolerance blood glucose range
7.8-11 mmol/l
Conduction velocity of A-alpha neurons
70-120 m/s
Diameter of A-beta fibers
8 microns
Frequency of alpha waves
8-13 Hz
How much of the sleep phase in a fetus does the REM phase occupy?
80%
How many amino acids does proinsulin consist of?
86
Above which undetected threshold is one deaf?
90 dB
How long is one sleep cycle?
90 minutes
Infradian cycle
>24 hr cycle
Why does iodine deficiency cause goiter?
A deficiency prevents the synthesis of T3 and T4 which means that there are no thyroid hormones synthesized. Thus, no negative feedback on TSH which will increase in production and cause the enlargement of the thyroid gland.
Which are the fastest and slowest fibers?
A-alpha are the fastest, C fibers are the slowest
Which fibers innervate the extrafusal fibers of the muscle spindle?
A-alpha motor neurons
Which fibers are characteristic of the DCML?
A-beta fibers
Which fibers are characteristic of the spinothalamic tract?
A-delta fibers and C fibers
Which motor/efferent fibers innervate the intrafusal fibers of the muscle spindle?
A-gamma motor neurons
Which hormones are secreted by the posterior pituitary?
ADH and oxytocin
Which frequency is the ultrasound?
Above 20 000 Hz
Neurotransmitter released by parasympathetic postganglionic fibers
Acetylcholine
Describe the process from the release of acetylcholine to the generation of AP in the skeletal muscle
Ach binds to acetylcholine receptors on the muscle cell membrane (sarcolemma) which causes opening of ligand gated Na+ channels, and Na+ will flow into the cell. This will cause a depolarization (EPP) of the sarcolemma and activate the fast voltage gated Na+ channels. This causes further inflow of Na+ and the generation of the AP (overshoot).
Where is prolactin produced?
Acidophilic cells of the anterior pituitary gland
What is echoic memory?
Acoustic memory
Increased levels of GH in adulthood
Acromegaly
Which requires more energy to be evoked, action potential or PSP?
Action potential, requires activation of fast voltage gated Na+ channels
Final outcome of the direct loop on the thalamus
Activation
Corresponding activation/inhibition for the direct loop: Cortex-striatum-pars interna-thalamus
Activation-inhibition-inhibition (all in all activation)
Corresponding activation/inhibition for the following pathway: Cortex-striatum-substantia nigra-thalamus
Activation-inhibition-inhibition (all in all activation)
Corresponding activation/inhibition for the indirect loop: Cortex-striatum-pars externa-subthalamic nucleus-pars interna-thalamus
Activation-inhibition-inhibition-activation-inhibition (all in all inhibition)
Where are leptin and CCK released from?
Adipose tissue
Causes of primary Addison's disease
Adrenal cortex failure
Which hormones can increase blood glucose?
Adrenalin, noradrenaline, glucagon, growth hormone, glucocorticoids, thyroid hormones, somatostatin (by inhibiting insulin)
Which hormones does proopiomelanocortin gene produce?
Adrenocorticotrope hormone (ACTH), melanocyte stimulating hormone (MSH), lipoprotein hormone (LPH), and beta-endorphin hormone
When are delta waves normal?
Adults in deep sleep, children anytime
Why can menopause result in a false positive hCG test?
After menopause, estradiol and progesterone levels decrease. There is no negative feedback on FSH and LH, which will increase. The high levels of FSH and LH can cross-react with hCG and give a positive test.
Which molecules can be synthesized from cholesterol?
Aldosterone/mineralocorticoids, cortisol/glucocorticoids, and androgens/sex steriods
Maximum threshold in compound AP
All axons are activated
Effect of alpha 1 receptors and beta 2 receptors in vessels (both adrenergic)
Alpha 1: vasoconstriction Beta 2: vasodilation
Components of hCG
Alpha and beta subunit
What subunits are glycoprotein hormones composed of?
Alpha and beta subunits
Function of outer hair cells
Amplify and modify the sound
What are the two main characteristics of muscle stimulus?
Amplitude and duration (pulse width) of stimulus
How is the antagonist muscle in the monosynaptic reflex relaxed?
An inhibitory interneuron can move in between the segments and inhibit the alpha motor neuron for the antagonist muscle.
What is observed in the compass reflex?
An intact frog is placed in a clockwise-rotating chamber, the intact frog turns antclockwise
Effect of 21-beta-hydroxylase enzyme deficiency on the synthesis of mineralocorticoids (aldosterone) and glucocorticoids (cortisol)
Androgenital syndrom (virilism), salt-losing form
Effect of 11-beta-hydroxylase enzyme deficiency
Androgenital syndrome, non-salt-losing form
Which molecules are synthesized in the case of 21-beta-hydroxylase deficiency?
Androgens/sex steroids
What stimulates the production of aldosterone?
Angiotensin II, hyperkalemia, hyponatremia, ACTH (adrenocorticotroph hormone)
Result of damage to the lateral hypothalamus
Anorexia (no feeling of hunger)
Where is the cooling center located?
Anterior hypothalamus
Which antibody is used in the immunological method (pregnancy test)?
Anti beta hCG antibodies
What can be seen in an estrus phase?
Anucleated epithelial cells
Minimum threshold in compound AP
At least 1 axon is activated
How many electrodes are needed to perform an EEG?
At least three electrodes
Characteristics of REM phase
Atonia, lack of thermoregulation, irregular autonomic function
Which drug can inhibit the pupillary reflex at the level of the pupillary sphincter muscle?
Atropine, blocks muscarinic acetylcholine receptors
What is Myasthenia gravis?
Autoimmune disease where antibodies are produced against the muscle type nicotinic acetylcholine receptors. This results in muscle weakness
What can be used to block nicotinic acetylcholine recpetors in the autonomic ganglion and motor end plate (separately)?
Autonomic ganglion: high dose of nicotine Motor end plate: curare/tubocurarine
Function of B fibers (type III fibers)
Autonomic preganglionic fibers
When do beta waves occur?
Awake adult, REM phase of sleeping
Where are the fast voltage gated Na+ channels located in C fibers?
Axon hillock and whole axon
Way of transport of hPL from hypothalamus to posterior pituitary gland
Axonal transport
Why does 21-beta hydroxylase deficiency result in salt-losing form of virilism?
Because no aldosterone is produced and therefore less Na+ is reabsorbed
Why is the concentration of glucose low in the ejaculate?
Because sperm cells consume glucose
Which parts of the rotational movements are detected by the semicircular canal?
Beginning and the end
Location of GLUT2
Beta cells of pancreas, liver, kidneys, and small intestine
Which subunit differentiates the glycoprotein hormones (FSH, LH, TSH, hCG)?
Beta subunit
Which subunit in glycoproteins is different?
Beta subunit
Where is the vitreous humor located?
Between the lens and the retina
Where in the cochlea is the organ of Corti located?
Between the scala media and the scala tympani
Difference between unipolar and bipolar leads
Bipolar leads: measure voltage difference between two electrodes Unipolar leads: measure voltage difference between different and indifferent electrode
What is the characteristic of the optic disc?
Blind spot with no photoreceptors
Tritanopia
Blue color blindness
What does an isoelectric line on an EEG indicate?
Brain death
Importance of the REM phase
Brain development in fetuses, conversion of short term memory to long term memory
What can delta waves in an awake adult indicate?
Brain disturbances
What can theta waves in an awake adult indicate?
Brain disturbances
Effect of decreased corticsol on CNS
Brain malfunctions
How are catecholamines metabolized?
By MAO-A (monoamino oxydase), MAO-B, and COMPT (cathecolamine ortho-methyl transferase)
How will alpha receptor blockers affect blood glucose levels and how?
By blocking alpha receptors, adrenaline cannot bind and will not inhibit the production and secretion of insulin. Insulin will be produced and the blood glucose levels will decrease.
Where is the hPL produced?
By the supraoptic and paraventricular nuclei of the hypothalamus
Which segments are tested in the biceps reflex?
C5-C6
Which segments are tested in the brachioradialis reflex?
C5-C6
Which segments are tested in the triceps reflex?
C6-C8
Which segments are tested in the brachioulnaris reflex?
C7-C8
Functions of thyroid hormones
CNS development in childhood and growth processes Increase metabolic rate Increase cell metabolism Increase number and function of mitochondria Increase blood glucose levels via increasing glucose uptake from the GI Increase heat production Increase sensitivity of adrenergic receptors
Activators of TRVP-1 receptors
Capsaicin (spicy food), ischemia of the heart, ischemia of skeletal muscle
Examples of infradian cycles
Cardiac cycle, respiratory cycle
Which is stronger from cathode make excitation and anode break excitation?
Cathode make excitation
Where is PTH produced?
Chief cells of parathyroid gland
How is aldosterone synthesized from cholesterol?
Cholesterol -> pregonolon -> progesterone -> 11-desoxy-corticosterone -> corticosterone -> aldosterone
Postrotational nystagmus
Contralateral nystagmus after rotation
Where in the spinal cord is the spinothalamic tract located?
Contralaterally in the lateral and anterior columns
Components of the accomodation triad
Convergence of eyeballs, pupil constriction, accomodation (lens becomes more convex)
How can presbyopia be corrected?
Convex lens
How is hypermettropia corrected?
Convex lens (converging lens)
Part of the eye with the highest refractive power
Cornea
What is astigmatism?
Cornea is not spherical so the refraction is different is different angles
Which reflexes are intact in spinal shock?
Corneal and pharyngela reflexes
List 7 exteroceptive reflexes
Corneal reflex, pharyngeal reflex, mamillary reflex, superficial abdominal reflex, creamster reflex, plantar reflex, anal reflex
Which reflexes can be investigated in an intact frog?
Corneal reflex, turning reflex, compass reflex, immobility reflex
Components of the indirect loop (basal ganglia)
Cortex-striatum-pars externa-subthalamic nucleus-pars interna-thalamus
Components of the direct loop (basal ganglia)
Cortex-striatum-pars interna-thalamus
Why does adrenal cortex cause hyperpigmentation?
Corticsol inhibits ACTH, without it the levels of ACTH will increase. This causes increased transcription of propriomelanocortin gene which stimulates MSH, causing hyperpigmentation
Which hormone is affected by addison's disease and in what way?
Cortisol levels are decreased
Reasons for primary Cushing syndrome
Cortisol overproduction
Where do the 1st neurons of the DCML synapse?
Cuneate or gracile nucleus
Endocrine reasons for diabetes mellitus
Cushing syndrome, giantism/acromegaly, pheocromocytoma, glucagonoma, somatostatinoma, hyperthyroidism
High decerebration
Damage above the red nucleus
Low decerebration
Damage between the pons and medulla
When can fertilization take place?
Day 12-16
What is observed in the wiping reflex?
Decapitated frog tries to move the patch with acetic acid away
What is observed in the embracing reflex?
Decapitated male frog embraces whatever is put between its limbs during mating season
Effect of cathelectrotonus on the threshold
Decreased
Effect of lidocaine and ether on the conduction velocity of nerve fibers
Decreased
Effect of glucose on glucose sensitive neurons
Decreased activity (after eating, BS increases, activity of glucose sensitive neurons decreases, less activity of LH-hunger center)
Effect of decreased temperature on conduction velocity
Decreased conduction velocity
Effect of anorexigenic molecules
Decreased food intake
Symptoms of hypothyroidism
Decreased metabolic rate, overweight, myxedema, low HR and BP
Effect of increased amino acid release from skeletal muscle as a result of glucocorticoid exposure
Decreased muscle mass and increased gluconeogenesis
How will cutting the dorsal fibers affect the muscle tone?
Decreased muscle tone (no input from Ia and II fibers)
What is anelectrotonus?
Decreased of excitability around the anode due to accumulation of negative charge (hyperpolarization)
Causes of decreased or absent pain sensation
Decreased sensitivity of nociceptors, adaptation of nocicpetors
Effect of alkalosis on concentration of free calcium
Decreased, plasma proteins release H+ and bind calcium
Treatments for Parkinson's disease
Deep brain stimulation and L-DOPA
Which types of waves (EEG) have the highest amplitude?
Delta
In a closed circuit, what happens around the cathode?
Depolarization (accumulation of positive ions)
Characteristics of beta waves
Desynchronized (short amplitude and high frequency)
Function of utricle
Detects horizontal acceleration
Function of saccule
Detects vertical acceleration
What is gestation diabetes?
Diabetes developed during pregnancy
Relation between diameter of fibers and conduction velocity
Directly proportional, the wider the faster
Explain briefly the 10-20 system for electrode placement
Distance between the nasion and inion is divided into portions of 10%-20%-20%-20%-20%-10%
Determination of nerve conductance velocity
Distance between the two recording electrodes (mm) divided by the time delay between the peaks on the two contraction curves (ms)
Types of biological rythms
Diurnal, infradian, utradian
Two types of somatosensory systems
Dorsal column meidal lemniscus and spinothalamic system
Where do the 1st neurons of the spinothalamic tract synapse?
Dorsal horn of the spinal cord
Why does LH and FSH increase towards the end of the luteal phase?
Due to the decrease in estradiol and progesterone which inhibit LH and FSH
Why does adrenal cortex cause low BP?
Due to unresponsiveness of catecholamines, water and electrolyte imbalance
Which organs produce calcitriol?
Liver, kidneys, skin
There is a lesion in the optic chiasm, which vision is affected?
Loss of temporal vision on the right and left eye (bitemporal hemianopia)
Characteristics of slow wave sleep
Low HR, low BP, low metabolic rate, low respiration, low muscle tone (energy conservation)
Characteristics of GLUT2
Low affinity (blood glucose should be higer than normal) and high capacity (a lot of glucose molecules can be taken up to produce adequate amount of insulin)
Which gradient works against the concentration gradient across the cell membrane?
Electrical gradient
What are the hair cells immersed in?
Endoplymph
Functions of A-beta fibers (type II fibers)
Epicritic sentation and secondary endings of muscle spindle/sensory fibers from proprioceptors
Type of sensation carried by the DCML
Epicritic: fine touch (two point disrimination, graphesthesia), vibration
Which hormone of the menstrual cycle is characterized by two peaks?
Estradiol
What is observed in the brachioulnar reflex?
Extension
What is observed in the patellar reflex?
Extension at the knee joint
What is observed in the triceps reflex?
Extension in the elbow
Auditory pathway
External acoustic meatus-tympanic membrane-malleus/incus/stapes-oval window-cochlea-organ of Corti-spiral ganglion-cochlear nerve-cochlear nucleus-superior olive-lateral lemniscus-inferior colliculus-medial geniculate body-auditory radiation-primary auditory cortex-wernicke's area
What is observed in the corneal reflex?
Eye blink after touching the cornea
Which muscles have a tone in the REM phase?
Eye muscles and respiratory muscles
Which stimulus can stop alpha waves?
Eye opening, light stimulus
Which hormone is characterized by a small peak before ovulation?
FSH
Other name for hypermettropia
Far sighted
What can evoke an epileptic seizure?
Flashing light, hyperventilation, sleeplessness
What is observed in the brachioradial reflex?
Flexion and supination
What is observed in the biceps reflex?
Flexion and supination in the elbow
What is the crossed extensor reflex?
Flexion of stimulated limb and extension of contralateral limb
In tonic neck reflexes, what does lowering the head result in?
Flexion of upper limbs and extension of lower limbs
Where are the light rays focused on the retina?
Fovea centralis
Which form of thyroid hormones is active?
Free form
neurotransmitters in inhibitory synapse
GABA and glycine
Types of molecules released by the fibers from the striatum to the pallidum
GABA, substance P, encephalin
What do acidophil cells in the anterior pituitary release?
GH and prolactin
Effect of GHRH on the anterior pituitary gland
GH release
What stimulates alpha cells?
GH, glucocorticoids, catecholamines, arginine
which glucose transporter is insulin independent?
GLUT2
Which type of glucose transporter is insulin dependent?
GLUT4
What is observed in the pharyngeal reflex?
Gagging
Which type of waves (EEG) have the lowest amplitude?
Gamma
Types of EEG waves
Gamma, beta, alpha, theta, delta
Increased levels of GH in childhood
Gigantism
In which zone of the adrenal cortex are mineralocorticoids produced?
Glomerular zone (outer layer)
What is tested in the pharyngeal reflex?
Glossopharyngeal and vagus nerves
Dominating hormone during post-absorptive phase
Glucagon
what is GLP-1?
Glucagon like peptide-1 (GLP-1): Secreted from L-cells of the ileum and colon (as well as neurons of the solitary tract) this hormone/neurotransmitter has a half-life of only 1-2 minutes, but has receptors in the brain, gut and pancreas. It stimulates insulin secretion by B-cells of the pancreas and suppresses appetite in the brain. GLP-1 analogs are now used in treatment of obesity in type 2 diabetes.
Describe the cellular mechanism of insulin production in beta cells
Glucose 6-P is produced from glucose and activates the preproinsulin gene. The preproinsulin gene codes for proinsulin which will differentiate into insulin and C peptide
Describe the cellular mechanism of insulin secretion in beta cells
Glucose is taken up by GLUT2 in the pancreatic beta cells. Glucose is phosphorylated into G6-P which undergoes glycolysis, TCA, and oxidative phosphorylation, producing ATP. ATP inhibits the ATP sensitive potassium channels, causing a depolarization of the cell membrane. The increase of the membrane potential activates the voltage gated calcium channels. The inflow of calcium ions causes a hypopolarization of the cell membrane which stimulates the exocytosis of vesicles containing C-peptide and insulin.
What type of fibers go from the subthalamic nucleus to pars interna?
Glutaminergic fibers
What kind of fibers does the striatum receive from the cortex?
Glutaminergic/excitatory fibers
Which neurotransmitter do the Renshaw cells use?
Glycine
Why does the long-term release of glucocorticoids cause an increase in glycogen synthesis?
Glycogen is synthesized in preparation for acute stress and the increased need for glucose this requires.
Which hormones are transported from the hypothalamus to the anterior pituitary via the portal circulation?
GnRH, GHRH, TRH, CRH
2 main types of epilepsy
Grand mal seizure, petit mal seizure
Deuter anopia
Green color blindness
What type of electrodes are used for EEGs?
Ground electrode Active/different electrode Passive/indifferent electrode
Reasons for a false negative pregnancy test with the immunological method
HCG levels are not high enough
What is a cholicarcinoma?
HCG producing tumor
Complications of diabetes mellitus
Heart failure, kidney failure, retinopathy, vasculopathy, neuropathy, stroke, delayed wound healing
Which hormone is increased after implantation?
Human chorionic gonatotropin (hCG)
Symptoms of hypoglycemia
Hunger, pale skin, sweating, tachycardia, irritability
What stimulates the production of calcitonin?
Hypercalcemia
Side effects of increased glucocorticoids
Hyperglycemia (steroid DM), muscle loss, central shift of adipose tissue, osteoporosis, high blood pressure, gastric ulcer, weak immune system
What is characteristic of DM2 at the start?
Hyperinsulinaemia
What happens to the photoreceptors when they absorb photons?
Hyperpolarization
What stimulates PTH?
Hypocalcemia
Effect of adrenal cortex failure (no glucocorticoids/mineralocorticoids)
Hypoglycemia, low blood pressure, inadequate stress response, hyperpigmentation
Where is tRH released from?
Hypothalamus
Where is the gonadotrope releasing hormone (GnRH) released?
Hypothalamus
Where is GHRH produced?
Hypothalamus (arcuate nucleus)
Which sensory/afferent fibers innervate the intrafusal fibers of the muscle spindle?
Ia (A-alpha) and II (A-beta) fibers
Which fibers innervate the golgi tendon organ?
Ib fibers (A-alpha)
Types of sensory memory
Iconic, echoic, taste, and smell
What is the anode break excitation?
Immediately after the circuit is opened, there is an accumulation of positive charge around the anode. This causes a depolarization which can travel towards the muscle when there is an open conduction between the two poles. This is only observed in medium stimulus with the cathode closer to the muscle
Special types of conditioning
Impriting, autoshaping, conditioned taste aversion, latent learning, curiosity
What is the Brondgest phenomenon?
In a decapitated frog, hanging from a hook, the hind leg is not hanging passively but has a certain flexor tone. This flexor tone is elicited by the gravitational force which stretches the muscle spindle
Main difference between compund AP and individual AP
In individual AP, the all or nothing law applies. An increase in stimulus intensity has no effect on the amplitude
Which receptors are only active in day time?
Cones
Which type of photoreceptors are important for photopic vision?
Cones
What is observed in the anal reflex?
Constriction of the anal sphincter
Why is the light focused on the fovea centralis?
Contains many cones
Anode is closer to the muscle, circuit is open, open conduction between the two poles, post strong stimulus. What is observed?
Contraction (anode break excitation)
What is observed in the abdominal reflex?
Contraction of the abdominal muscle
What is observed in the cremaster reflex?
Contraction of the ipsilateral cremasteric muscle
What is observed in the superficial abdominal reflex?
Contraction of the ipsilateral muscle
Characteristics of myogenic lesion
Contraction with low amplitude
Which directions can nystagmus be observed in?
Horizontal, vertical, rotational
Examples of diurnal cycles
Hormones, body temperature, and sleep/wake cycle
What stimulates free nerve endings?
Hot, cols, local acidosis
Which hormone increases at the beginning of pregnancy until week 10 and then decreases?
Human chorionic gonadotropin hormone (hCG)
What is hemiballism?
Involuntary large movement on one side of the body
Where in the spinal cord is the CDML located?
Ipsilaterally in the dorsal column
In Brown sequard syndrome, which functions are lost below the level of injury and on which side?
Ipsilaterally: motor function and epicritic sensation Contralaterally: protopathic sensation
In Brown sequard syndrome, which functions are preserved below the level of injury and on which side?
Ipsilaterally: protopathic sentation Contralaterally: motor functions and epicritic sensation
What type of issues arise in vitamin A deficiency?
Issues with scotopic vision (night vision)
How does calcitonin act?
It acticated osteoblasts and calcium is absorbed into the bone
Why is L-DOPA used instead of dopamine?
It can cross the blood-brain barrier
Which side of the body presents hemiballism compared to location of subthalamic nucleus lesion?
Contralateral
There is a lesion in the left optic nerve, which vision is affected?
Complete loss of vision on the left eye (left eye anopia)
There is a lesion in the right optic nerve, which vision is affected?
Complete loss of vision on the right eye (right eye anopia)
Possible causes of neuropathic pain
Compression of sensory neuron/spinal cord, spontaneous activity of nociceptors, thalamus, cortex, malfunction of periaqueductal gray matter, phantom pain, psychogenic pain
How is myopia corrected?
Concave lens (diverging lens)
Capacity of sensory memory
High
Effect of Conn-syndrome (hyperaldosteronism)
High BP, hypokalemia, high blood pH (metabolic alkalosis), low levels of free calcium
What can inhibit nicotinic acetylcholine receptors
High dose of nicotine
Difference between high and low decerebration (symptoms)
High: righting reflex and locomotion can be evoked Low: no righting reflex or locomotion, hyperreflexia
Dominating hormone during nutrient absorption phase
Insulin
Other name for DM1
Insulin dependent diabetes mellitus
Causes of diabetes mellitus type 2
Insulin resistance, decreased sensitivity of insulin receptors, genes, lifestyle
What inhibits alpha cells?
Insulin, somatostatin, and glucose
What is observed in the immobility reflex?
Intact frog is placed on its back and pushed down on the sternum then released without touching the legs. The frog will lie still/play dead
What is observed in the turning reflex?
Intact frog turns back to its original position after being placed on its back
Why is the amplitude of the AP constant?
It is restored at the nodes of Ranvier via fast voltage activated Na+ channels
Target organs of aldosterone
Kidneys (collecting ducts), salivary glands, sweat glands, colon, and gallbladder
What is tested in the cremaster reflex?
L1-L2 segments
Which segments are tested in the patellar reflex?
L2-L4
Which hormone of the menstrual cycle is characterized by a big peak before ovulation (day-14)?
LH
Effect of GnRH from hypothalamus on anterior pituitary gland
Stimulates release oof FSH and LH
Which organ does GH affect and how?
Stimulates the release of somatomedin from the liver (e.g IGF-1)
Effect of LH on GnRH in late follicular phase when estradiol is high
Stimulation
Effect of insulin on lipoprotein lipase
Stimulation
Which structure in the scala media produces the endolymph?
Stria vascularis
Which neurotransmitters are involved in the pain pathway
Substance P, encephalin, endorphins
What kind of innervation do blood vessels have?
Sympathetic
Symptoms of spinal shock
Sympathetic dysfunction (low BP, TPR, no ejaculation), cold extremities/no peripheral thermoregulation, parasympathetic dysfunction (passive incontinence, no erection)
Innervation of adrenal medulla
Sympathetic preganglionic fibers (Ach)
What causes pale skin, sweating, and tachycardia in hypoglycemia?
Symphathetic activation
Characteristics of alpha waves
Synchronized (low frequency, high amplitude)
How can the eye accomodate to an object far away?
The ciliary muscles relax, zonular fibers tighten and pull the lens which becomes less concave and is able to focus on that object
Difference in experimental setup between investigation of polar excitement and Pflüger's law
The conduction between the anode and cathode is not blocked in the Pflüger investigation; no NH4+ block.
Why do levels of estradiol and progesterone decrease at the end of the luteal phase?
The corpus luteum dies (becomes corpus albican which does not secrete progesterone or estrogen)
What causes the refractory period in neurons?
The fast voltage gated sodium dependent channels have an inactivation gate that needs to be reset after an AP. The time taken for the inactivation gate to reset back into the activation gate is the refractory period within which no AP can be elicited.
Thermal nystagmus
Warm water is poured inside the ear, increasing the temperature of the vestibular system and inducing perilymph movement. Warm water will cause ipsilateral nystagmus while cold water will cause contralateral nystagmus.
Symptoms of hyperthyroidism
Weight loss, exophtalamus, high HR, high systolic BP and blood glucose
Where does the issue reside in sensory aphasia?
Wernicke's area
