XI: Chapter 21- Neural control Flashcards
Ganglion first appeared in which phylum?
Platyhelminthes
Brain like structure first which appeared in which organisms?
Insects
How does the antiport in sodium potassium pump work?
Influx of 2 K+ for outflux of every 3 Na+
In resting stage the axolemma is permeable to which ion and impermeable to which ?
Impermeable to Na+ and permeable to K+
What is the relative charge on the outside of the axolemma in resting state?
Positive
What is the resting membrane potential of axolemma?
-70mV
In depolarised stage, what is the axolemma membrane potential?
+30 to +45 mV
How long does it take for the sodium channels opened in depolarised stage to close during impulse generation in an axon?
1 ms
What happens to the sodium and potassium channels in the repolarised stage of axolemma?
Sodium channels close, potassium channels open
What is the axolemma membrane potential during hyperpolarisation?
-90 mV
Polarised stage of axolemma is maintained by
Sodium potassium pump
Depolarised stage of axolemma is caused by
Sodium channel opening
Repolarised stage of axolemma is caused by
Potassium channel opening
What is absolute refractory period of an axon?
Nerve does not generate new impulse irrespective of the strength of stimulus. (3-4 ms)
What is the relative refractory period of an axon?
Impulse can be generated by giving higher stimulus
What is threshold stimulus?
-55mV
Conduction of impulse is bidirectional in a myelinated neuron. True/false?
False. It is unidirectional.
What happens to the speed of conduction of impulse if the diameter of nerve fibre increases?
Velocity also increases
WHich is the most common type of synapse based on the parts of neurons involved?
Axo-dendritic synapse
Which synapse-electrical or chemical has narrow synaptic cleft?
Electrical
Which synapse-electrical or chemical has synaptic vesicles?
chemical
Which synapse-electrical or chemical is common?
Chemical
Which ion is involved in transmission of a chemical synapse?
Calcium ions
What are excitatory neurotransmitter?
Open sodium channels to cause depolarisation of axolemma. Impulse is carried forward
What kind of neurotransmitter is acetyl choline?
Excitatory neurotransmitter
What kind of neurotransmitter is epinephrin?
Excitatory neurotransmitter
How do inhibitory neurotransmitters function?
Cause chlorine channels to open => hyperpolarisation of axolemma => impulse is blocked
What kind of neurotransmitter is GABA?
Inhibitory neurotransmitter
What kind of neurotransmitter is serotonin?
Inhibitory neurotransmitter
What kind of neurotransmitter is dopamine?
Can function as both inhibitory and excitatory neurotransmitter
If nodes of Ranvier become absent on axons then what will happen to the impulse conduction?
Impulse conduction will stop
What are the parts of motor nervous system?
Somatic and autonomous nervous system`
What tissue is present in meninges?
Connective tissue
How many meninges are present in fishes?
1
How many meninges are present in amphibians?
2
How many meninges are present in humans?
3
How many meninges are present in reptiles?
2
How many meninges are present in birds?
2
Name the meninges of mammals in the inside to outside order.
Piamater
Arachnoid mater
Duramater
Which is the thinnest meninx of mammalian brain?
Piamater
Vili are present in which meninx of mammalian brain?
Arachnoid mater
Subarachanoid space is present between which two meninx?
Between arachanoid mater and piamater
Subdural space is present between which two meninx?
Between duramater and arachanoid mater
What is present in subarachanoid space?
CSF
What is present in subdural space?
Serous fluid
Where is epidural space present?
Between duramater and vertebrae of spinal cord
What is epidural space made of?
Adipose tissue
What is the pH of cerebro spinal fluid?
7.3
Cerebro spinal fluid is formed by the filteration of
Blood
Are RBCs present in CSF?
No
What part of brain forms CSF?
Choroid plexus
CSF is withdrawn from which lumbar in lumbar puncture method of diagnosis?
L3 -L4
Spinal anasthesia is administered through which vertebrae?
L3-L4
How much CSF is produced everyday?
500ml
What are the cavities of brain called?
Ventricles
How many ventricles are present in brain?
4
What are the two lateral ventricles of brain called?
Paracoel
Where are the paracoel present?
Cerebral hemispheres
Where is the fourth ventricle of brain present and what is it called?
Present in medulla and called metacoel
The fourth and third ventricle of brain communicate through
Iter’s canal/aqueduct of sylvius
The lateral ventricles of the brain communicated with the third ventricle through
Foramen of monero
CSF from fourth ventricle of brain enter subarachnoid space through
2 lateral foramen of Luschka
1 median foramen of Magendie
What type of axons are present in the grey matter?
Non-myellinated neurons
What type of axons are present in the white matter?
Myelinated neurons
How are the white and grey matter arranged in brain?
Grey matter surrounds white matter
How are the white and grey matter arranged in spinal cord?
White matter surrounds grey matter
What is rhombencephalon?
Hind brain
What is prosencephalon?
Forebrain
What are the parts of forebrain?
Olfactory lobes, cerebrum, diencephalon
What are the parts of midbrain?
Optic lobes, cerebral peduncles
What are the parts of hind brain?
Pons varolii, medulla oblongata, cerebellum
How many olfactory lobes are present in forebrain?
1 pair
On which surface of brain are the olfactory lobes located?
Ventral surfaces
What is the largest part of the forebrain?
Cerebral hemispheres/cerebrum
The medulla of cerebral hemisphere is formed by
White matter
What is the thickest portion of cortex of cerebrum?
Neopallium
Name the fissures present in the cerebrum?
Central fissure
Parieto occipital fissure
Lateral/sylvian fissure
Central fissure of brain divides
Frontal and parietal lobes
Sylvian fissure of brain divides
frontal and parietal lobe from temporal lobe
Name the lobes of the brain.
Frontal
Parietal
Temporal
Occipital
In which lobes are the sensory area of cerebrum located?
Parietal, occipital and temporal lobes
In which lobes are the motor area of cerebrum located?
Frontal lobe
In which lobes are the association area of cerebrum located?
in all lobes
Which centre of brain controls involuntary muscles? In which lobe of cerebrum is it present?
Premotor centre in frontal lobe
Brocha’s speech centre is located in which lobe of the cerebrum?
Frontal lobe
Intellectual centre of brain is located in which lobe?
Frontal lobe
Which centre of brain is responsible for sensation of pain, pressure, heat, cold or activity like reading? In which lobe of cerebrum is it present?
Somesthesia centre present in parietal lobe
Gustatory centre is present in which lobe of cerebrum?
Parietal lobe
Centre of vision is present in which lobe of cerebrum?
Occipital lobe
Olfactory centre is present in which lobe of cerebrum?
Temporal lobe
Which centre of brain is responsible for understanding language? In which lobe of cerebrum is it present?
Wernicke’s area, temporal lobe
Auditory centre is present in which lobe of cerebrum?
Temporal lobe
The posterior part of forebrain is called
Diencephalon
Pineal gland is present on
Epithalamus (roof of Diencephalon)
Which part of brain is also called gatekeeper of cerebrum?
Thalamus
Hypothalamus connects to pitutary gland by
Infundibulum
What does the posterior surface of hypothalamus have?
Mammillary bodies
Hunger, thirst and satiety centre is present in
Hypothalamus
Thermoregulation is the function of
Hypothalamus
Limbic systems surrounds
Corpus callosum and thalamus
Limbic system includes
Thalamus, hypothalamus, amygdala, mammillary body and hippocampus nuclei
What is corpora quadrigemina?
4 optic lobes of mammalian brain
What are the four optic lobes?
2 superior colliculi
2 inferior colliculi
Which optic lobes are related to visual relex?
2 superior colliculi
Which optic lobes are related to auditory reflex?
2 inferior colliculi
Basal ganglia is
Subcortical nuclei at base of brain
Which is the largest nuclei of the basal ganglia?
Corpus striatum
What is the neurotransmitter of basal ganglia?
Dopamine
What has the subconcious control over the contraction of voluntary skeletal muscles?
Basal ganglia
What surrounds the aqueduct of sylvius?
Mid brain
What connects cerebrum to cerebellum?
Pons varolli
Peristalsis is controlled by which part of brain?
Medulla oblongata
Brain stem constitutes
Mid brain, medulla oblongata, pons
What is called the gateway to consiousness?
Reticular activating system
What is arbor vitae?
White matter in form of tree branching in cerebellum
What is crura cerebri?
Nerve tract of midbrain
Which part of brain converts short term memory to long term memory?
Hippocampus
What is the location of spinal cord?
Inside neural canal between vertebrae
What are the two swellings in spinal cord?
Cervical and lumbar
What is conus medullaris?
Posterior neural end of spinal cord
What is filum terminade?
Non nervours posterior extension of spinal cord
What is the tail like collection of roots of spinal nerves at posterior end called?
Cauda equina
Which cells line the central canal of spinal cord?
Ependymal cells
Which part of brain controls emotions?
Amygdala
Filum terminade is made of
Piamater
How many spinal nerves are present in humans? Give the spinal formula
31
C8 T12 L5 S5 Cd1
What type of nerves are spinal nerves?
Mixed nerves
Dorsal root of spinal cord arises from
Dorsal horn
Ventral root of spinal cord arises from
Ventral horn
Which fibres are present in the dorsal root of spinal cord?
Sensory fibres
Which nerve fibres are present in the ventral root of spinal cord?
Motor nerve fibres
Dorsal root ganglion cell bodies are present in
Dorsal root of spinal cord
Ventral root ganglion cell bodies are present in
Grey matter of spinal cord
How many cranial nerves are present in amphibians?
10
How many cranial nerves are present in reptiles?
12
How many cranial nerves are present in birds?
12
Name all 12 cranial nerves in order
Olfactory nerve I Optic nerve II Occulomotor nerve III Trochlear nerve IV Trigeminal nerve V Abducens nerve VI Facial nerve VII Auditory nerve VIII Glossopharyngeal nerve IX Vagus nerve X Spinal accessory nerve XI Hypoglossal nerve XII
Which is the I (first) cranial nerve?
Olfactory nerve
Which is the II cranial nerve?
Optic nerve
Which is the III cranial nerve?
Occulomotor nerve
Which is the IV cranial nerve?
Trochlear nerve
Which is the V cranial nerve?
Trigeminal nerve
Which is the VI cranial nerve?
Abducens nerve
Which is the VII cranial nerve?
Facial nerve
Which is the VIII cranial nerve?
Auditory nerve
Which is the IX cranial nerve?
Glossopharyngeal nerve
Which is the X cranial nerve?
Vagus nerve
Which is the XI cranial nerve?
Spinal accessory nerve
Which is the XII cranial nerve?
Hypoglossal nerve
Which cranial nerves are sensory nerves?
I, II, VIII
Which cranial nerves are motor nerves?
III, IV, VI, XI, XII
Which cranial nerves are mixed nerves?
V, VII, IX, X
Which is the longest cranial nerve?
Vagus nerve
Which is the shortest cranial nerve?
Abducens nerve
Which is the largest cranial nerve?
Trigeminal nerve
Which is the thinnest cranial nerve?
Trochlear nerve
What is the function of occulomotor nerve?
Movement of superior rectus, inferior rectus, medial rectus, inferior oblique muscles
Where does the occulomotor nerve originate?
Midbrain
What is the function of trochlear nerve?
Eye rotation- superior oblique muscle
Where does the trochlear nerve originate?
Midbrain
What is the function of trigeminal nerve?
Sensations from conjunctiva, eyelids, lacrimal glands, cheeks, upper and lower lips, jaw movement
What are the three major branches of trigeminal nerve?
the ophthalmic nerve (V1), the maxillary nerve (V2) and the mandibular nerve (V3)
Which cranial nerve is called dentist’s nerve?
Trigeminal nerve
Abducens nerve arises from
Pons
What is the function of abducens nerve?
Eye rotation, lateral rectus
Facial nerve arises from
Pons
Auditory nerve arises from
Pons
Glassopharyngeal nerve arises from
Medulla
Vagus nerve arises from
Medulla
Which nerve is responsible for speech, swallowing, peristalsis, heart rate, etc?
Vagus nerve
Which nerve controls the muscle of tongue?
HYpoglossal nerve
Spinal accessory nerve arises from
Medulla
Hypoglossal nerve arises from
Medulla
Which scientists conducted bell dog experiment?
Ivan pavlov
Which part of autonomous nervous system works under stress?
Sympathetic nervous system
What is the neurotransmitter of sympathetic nervous system?
Adrenaline
How many sympathetic ganglion are present in the body?
21
3 cervical, 12 thoracic, 5 lumbar, 1 saccral
What is the neurotransmitter of parasympathetic nervous system?
Acetyl choline
Which part of autonomous nervous system has thoraco lumbar outflow?
Sympathetic nervous system
Which part of autonomous nervous system has cranio-sacral outflow?
Parasympathetic nervous system
Where is sympathetic nervous system located?
Near spinal cord
Where is parasympathetic nervous system located?
Near organs
The pre ganglionic fibre is shorter in which- sympathetic or parasympathetic nervous system?
Sympathetic nervous system
The post ganglionic fibre is shorter in which-sympathetic or parasympathetic nervous system?
Parasympathetic nervous system
Out of sympathetic and parasympathetic nervous system, which works on mode of conserving energy?
Parasympathetic nervous system
Which nervous system makes the pupil of eye dilate?
Sympathetic nervous system
Which nervous system increases salivation?
Parasympathetic nervous system
Which nervous system increase blood pressure?
Sympathetic nervous system
Which nervous system causes dilation of bronchi and trachea?
Sympathetic nervous system
Which nervous system causes contraction of anal sphinctre?
Sympathetic nervous system
Basket nerve endings are present at
Root of hair follicles
Merkel’s disc is located in
Epidermis
Merkel’s disc senses
Touch
Meissner’s corpuscles are present in
Dermis
Meissner’s corpuscles sense
Deep touch
Pacinian corpuscle are present in
Deep dermis
Pacinian corpuscles sense
Pressure
Which thermoreceptors sense warmth?
Caloreceptors
Which thermoreceptors sense cold?
Frigidoreceptor
Which muscle of eye helps in upward movement?
Superior rectus
Which muscle of eye helps in inward movement?
Medial rectus
Which muscle of eye helps in outward movement?
Lateral rectus
Name the glands present in eyelids.
Meibomian gland
Gland of Zeis
Gland of Moll
Which is the first refractive surface of eye?
Cornea
Is cornea supplied with blood vessels?
No
cornea receive glucose from
Aqueous humour
Which layer provides nourishment to retina?
Choroid
Is choroid supplied with blood vessel?
Yes
Which forms the second refractory surface of eye?
Lens
Aqueous chamber of eye is present between
Cornea and lens
Aqueous chamber of eye drains into venous circulation through which structure?
Canal of schleim
How mant sublayers does retina have? Name them
4 Pigment layer Photosensitive layer Bipolar neuron layer Retinal ganglionic layer
Horizontal cells in eye are present between
Photosensitive cells and bipolar neuron layer
Amacrine cells in eye are present between
Bipolar neuron and ganglionic layer
Which cells are more abundant- rods or cones?
Rods
Which pigment is present in rods?
Rhodoposin
Which cells of eye provide scotopic vision?
Rod cells
Which pigment is present in cones?
Iodopsin
Visual purple is the other name for
Rhodopsin
Visual violet is the other name of
Iodopsin
Rhodopsin is made of
Retinal + opsin
What is macula lutea?
Area on retina just opposite to lens where only cones are present
In which part of retina is the sharpest image formed?
Macula lutea
What is fovea centralis?
Depression in macula lutea
Myopia is also known as
Near sightedness
Myopia is caused by
Increasing converging power of lens or decreased size of eyeball
Myopia can be corrected by using which lens?
Concave lens
Hypermetropia is also called
Far sightedness
Hypermetropia is caused due to
Decreasing convergence of lens or smaller eyeball
Hypermetropia is corrected by which lens?
Convex lens
Ear ossicles are present in which part of ear?
Middle ear
Which part of external ear has ceruminous glands?
External auditory meatus
Tympanum is made of which tissue?
Connective tissue
Tympanic cavity is filled with which fluid?
Air
Stapes connects to
Incus and oval window
Which joint is present between malleus and incus?
Saddle joint
Which joint is present between malleus and incus?
Saddle joint
Which joint is present between incus and stapes/
Ball and socket joint
Eustachian tube extends from inner ear to pharynx. True/false?
False
Eustachian tube extends from middle ear to pharynx.
What is the function of vestibular apparatus of ear?
Maintaining body balance
What is the sensitive structure of utriculus and saculus?
Macule (2)
What is the sensitive structure of semicircular canals?
Cristae
Scala vestibuli is filled with
Perilymph
Scala media of cochlea is filled with
Endolymph
Scala tympani is filled with
Perilymph
Which part of cochlea is connected to the oval window?
Scala vestibuli
Which part of cochlea contains organ of corti?
Scala media
Which part of cochlea is connected to round window?
Scala tympani
What are otolith crystals?
Calcareous crystals on top of gelatinous layer in macula. Responsible for maintenance of static pressure.
What is responsible for dynamic equilibrium of body?
Semicircular canal
Otolith crystals are found in which part of ear?
Macula
Organ of corti is present on which membrane of cochlea?
Basilar membrane
What is the function of somatic nervous system?
Transfers impulse from skeletal muscles to CNS
What is the function of autonomous nervous system?
Transfers impulse from CNS to involuntary muscles
What is the layer of cells which covers the cerebral hemisphere called?
Cerebral cortex
Cerebellum has fibre tracts that interconnect different regions of brain. True/false?
False.
Cerebellum has very convoluted surface while pons has fibre tracts that interconnect different regions of brain.
What is the external layer of eye composed of and what is it called?
Dense connective tissue, sclera
What is the colour of choroid?
Blue
How does choroid vary over the eyeball?
Thin over the posterior two thirds but becomes thick around anterior region to form the ciliary body
Tectorial membrane is a thin elastic membrane, true or false?
True
