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Flashcards in Nervous system Deck (46):

Nervous system enable us to ....

- Detect stimuli
- Process stimuli
- Respond to stimuli
(either consciously or unconsciously)


Role of endocrine system

- Productions of chemical message (hormones) into blood and deliver to target cells
- Primary controls metabolic functions


Role of nervous system

- Rapid transmission of electrical impulse along or between nerve cells
- Affect target cells by releasing chemical messengers (neurotransmitter)
- Generally coordinates more rapid activity (e.g. muscle movement)
- very important in controlling interaction with the external environment


Draw and name the neuron structures

Dendrites, Axon hillock, Nucleus, Soma (Cell body), Axon, Axon terminals, Schwann cells, Node of Ranvier
[Presynaptic neuron/ Synaptic Cleft/ Prosynaptic neuron]


The length of axon can be _______

- Top to bottom of the spinal cord
- From spinal cord to toes and fingers


A stimulus is usually transmitted from one neuron to another by _______

the movement of neurotransmitter substance across the synapse (Synaptic cleft)


Components of the nervous system

Central nervous system (CNS)
- Brain
- Spinal Cord

Peripheral nervous system (PNS)
- Various groups of nervous fibres that carry information between CNS and periphery (rest of the body)


Different regions of brain

Cerebral Cortex - Thinking / Movement / Vision

Brain stem - Breathing/ Blood pressure / Swallowing / Coughing / Reflexes / Eye movements / Auditory / Visual relays

Cerebellum - Coordination of movement / posture


Role of peripheral system

Transport information to and from CNS


Peripheral system contains ...

Nerve cells and other nerve structure other than CNS


Peripheral system can divided into -----

Afferent System - carry information to CNS about the internal and external environments

Efferent System - Carry information from the CNS to effector organs


Efferent System can divided into ----

Somatic nervous system (under conscious control)
- motor neurons that direct skeletal muscles

Automatic nervous system (involuntary)
- nerve fibres that act on smooth muscle and cardiac muscles and glands


Automatic nervous system can subdivided into ----

parasympathetic nerve fibres and sympathetic nerve fibres


Parasympathetic nerve fibres WORKS AGAINST sympathetic nerve fibres. How?

Parasympathetic system regulates involuntary activities that maintain the normal condition

Sympathetic system regulates involuntary activities that are important in the body's response to the stressful situration


Name 5 organs that works under the parasympathetic system; Name 2 doesn't

Work - Eye / Oral & nasal mucosa / salivary glands / Heart / Trachea / Stomach / Liver / Abdominal vessels / Pancreas / Adrenal Medulla / Small intestine / Large intestine / Kidney

Not work- Bladder/ genitals


Describe ' Rest & Digest response'
Which system it works under?

- Works under parasympathetic system
- Body relax to gear towards energy conservation and re-fuelling
- Blood pressure lower, heart beats slower, digestive system becomes more active


where are the cell bodies of the parasympathetic nervous system located?

In the sacral region of the spinal cord and the medulla


What is ganglia?

Where Preganglionic fibres are project to


What is the name of fibre that linked to the sacral region and medulla that works under the parasympathetic system?

Preganglionic fibres


What is use between the synapses of preganglionic fibre and ganglia

Neurotransmitter Acetylcholine


What is acetylcholine

the neurotransmitter used between preganglionic fibre and ganglia; post- ganglionic fibre and target organ


What is use between the synapses of post - ganglionic fibre and target organs



Name 5 organs that works under the sympathetic system; Name 2 doesn't

Work with all - Eye / Oral & nasal mucosa / salivary glands / Heart / Trachea / Stomach / Liver / Abdominal vessels / Pancreas / Adrenal Medulla / Small intestine / Large intestine / Kidney/ Bladder/ genitals


Describe " Fight or flight" response

- Body geared towards energy expenditure & muscular activity, to response to stress (e.g. exercise or strong emotions)
- Speeds up heart rate, blood pressure and respiration rate, sending more oxygen to muscles
- Pupils dilate to allow more light into the eyes
- Digestive system activities slows down
- Perception of pain diminishes


The cell bodies of sympathetic system are located ________

In the Thoracic and Lumbar spinal cord


Axons of sympathetic system neuron goes to ________

a chain of ganglia located near the spinal cord


Synapses between the sympathetic system neuron and ganglia use ______



Post- ganglionic neuron projects to target organs for stress response using __________ as neurotransmitter

(except for sweat glands)


Describe the knee- jerk reflex

- A stimuli is detected, A sensory neuron (PNS afferent system) send the signal to CNS to process the stimuli.
- CNS response via Interneuron (CNS)
- Interneuron relay to motor neuron (PNS, efferent system) (in this case, somatic nervous system)


In the sensory system, there are different ________ activated by stimuli in the environment

Sensory receptors


Name different types of sensory receptors

- Machanoreceptors > in skin, ear
- photoreceptors > eye
- Chemoreceptors > Tongue, olfactory mucosa
- Themoreceptors > Skin
- Nociceptors >Skin


Sensory receptors transmit information to the CNS via _______nerve fibres of the ____

afferent nerve fibres of the PNS


Name the eye structure

~ Pupil - entry of light
~ Lens - focusing of ligtht
~ Fovea - light is focus on this part of retina
~ Optic nerve
~ Photoreceptors - located on the retina
[ 2 types: Rods - sensitive to the low intensity light; Cones - function best in daylight , involved in colour vision]


Describe the 2 types of photoreceptors and how they response to stimuli

Rods and cones both contain a light- sensitive pigment, Rhodopsin, which isomerises when light strike the cells > causes a chain of events resulting in an electric impulse, carried by the afferent neuron (PNS) from the optic nerve to the CNS.
The interpretation also involves the parietal lobe and the temporal lobe


In the auditory system, name the ear structure

External ear
- Collects and directs sound waves
- Air filled, separated from middle ear by the tympanic membrane

Middle ear
- Transfer and amplifies sound waves
- Contain 3 tiny bones (auditory ossicles)
- Air filled

Inner ear
- Sense pitch, loudness, sign transduction occurs in the cochlea (hearing) & vestibular apparatus (balance)
- Fluid filled


The 3 tiny bones in middle ear

Malleus, incus, stapes


What happen in the middle ear?

The malleus (hammer) push upon the incus (anvil), which push upon the stapes (stirrup)


How the auditory system response to stimuli?

- Sounds wave cause the tympanic membrane to vibrate
> this makes the auditory ossicles vibrate and the stapes is pushed into the oval window
> fluid in the cochlea is displaced - cilia of the machanoreceptors auditory hair cells inside the cochlea is vibrate
> signal transduction > excitation of the afferent cochlear nerves > CNS (thalamus > temporal and parietal lobe)


name the structures in gustation

Tongue, papilla, taste bud, taste pore, taste receptor cell, sensory nerve fibre, palate, pharynx, larynx


How the gustation system response to stimuli?

Water soluble taste molecule > taste receptor cells > signal transduction > excitation of afferent taste nerve > CNS [medulla (in the brain stem) > thalamus > frontal lobe]


Structure of the olfactory system

- Nasal cavity lined with olfactory epithelium
- Contain chemoreceptor cells


How the olfactory system response to stimuli?

Odorant molecule binds to the cilia of the olfactory receptor cells (afferent neurons) > the olfactory nerve send signal to the CNS (Thalamus, hypothalamus, frontal lobe)


Skin structure

Epidermis / Dermis / Sweat gland / follicle / oil glands/ fatty tissue / Nerve


Skin has different receptor cells:____

Thermoreceptors: hot (> 36 oC) / cold (<36 oC)

Nociceptors (pain receptors): respond to extreme temperature, mechanical or chemical response

Mechanoreceptors (various structures)


Difference between hairy skin structure and non- hairy skin structure

- Pacinian corpuscle (very fast adapting)
- Hair follicle receptors (fast adapting)
- Ruffini's corpuscle (slow adapting)
- Tactile (slow adapting)

- Pacinian corpuscle (very fast adapting)
- Meissner's corpuscle (fast adapting)
- Merkel's receptors (slow adapting)


How skin sensory receptors response to stimuli?

- Rapidly adapting mechanoreceptors response to changes in velocity/ direction of stimuli (like vibration/ tapping)
- Slower one response to to stretching and intense stimuli