Coordination and Control In Humans Flashcards
What receptor is for sight and what is its energy of stimulus
Rod or cone cell in retina
Light
What receptor is for taste and what is its energy of stimulus
Taste buds on tongue
Chemical potential
What receptor is for smell and what is its energy of stimulus
Olfactory cells in nose
Chemical potential
What receptor is for pressure and what is its energy of stimulus
Pacinian corpuscles in skin
Movement and pressure
What receptor is for touch and what is its energy of stimulus
Meissner’s corpuscles
Movement and pressure
What receptor is for temperature and what is its energy of stimulus
Ruffini’s ending in skin
Heat
What receptor is for placement of limbs and what is its energy of stimulus
Proprioceptors (stretch receptors)
Mechanical displacement/stretching
What receptor is for balance and what is its energy of stimulus
Hair cells in semicircular canals in ear
Movement
What receptor is for hearing and what is its energy of stimulus
Hair cells in cochlea
Sound
Striated muscle
Type of muscle tissue in skeletal muscles. The muscle fibre haves regular striations that can be seen under light microscope
Cells surface membrane of a muscle fibre
Sarcolemma
The cytoplasm of muscle cells
Sarcoplasm
Receptor cell
A cell that responds to a particular stimulus by initiating an action potential
How does thickness of exons affect transmission speed
Thicker axons transmit impulses faster than thin ones as their resistance to the flow of ions is less. In small axons organelles makes less space for ions
Transducer
Converts one form of energy to another
Where are transducers found
Sensory organs
Specialised cells
Detect a specific stimulus and influence electrical activity of a spectate sensory neurone
What parts of sensory neurones are receptors
The ends
Pacinian corpuscle
Mechanoreceptor found deep in the skin made up of sensory neurones with named nerve ending surrounded by capsule
What is the Pacinian corpuscle capsule made of
Concentric rings (lamellae) floating in a viscous gel
What happens when pressure is applied to Pacinian corpuscle
Firm pressure deforms naked neurone
Light pressure is absorbed by many rings and gel
What happens when naked neurone in Pacinian corpuscle is deformed
Sodium channels open and neurone depolarises and action potential is triggered
8 steps stimulus to nerve impulse detection of salty food
Sodium ions diffuse through highly selective channel proteins in csm of microvili of chemoreceptors cells in taste buds
2 cms is depolarised
3 incrwae in positive charge jn cell- receptor potential
4 enough sodium ions in mouth- large receptor potential- voltage gated calcium ion channels open
5 Valium ions renter cytoplasm
6 vesicles containing neurotransmittter move tk cms and release neurotransmitter by exocytosis
7 if stimulus is above threshold action potential stimulated
8 sensory neurone transmits nerve impulses to taste centre in cerebral cortex of brain
Neurone
A nerve cell
Nerve
A bundle of neurones/ nerve cells
Differences between motor and sensory cell
Cell body at end vs part way along
Located in grey matter in the middle of spinal chord vs dorsal root ganglion
Cns to effector vs receptor to cns
Stimulates muscles to contract vs transmits information about stimulus to cns
Relay neurones are also known as
Multipolar neurones
What do dendrites do
Receive signals at synapses
Are relay neurones mainly myelinated or unmylinated
Unmylinated
What are thick filaments made from
Myosin
What are thin filaments made from
Actin
H band
Only myosin filaments present
I band
Only thin actin filaments present
A band
Contains areas where only myosin filaments are present and where myosin and actin overlap
M line
Attachment for myosin filaments
Z line
Attachment for actin filaments in the middle of I band
Sarcomere
Section of myofibril between two z lines
What blocks the myosin binding sites on actin
Tropomyosin
What part of myosin binds to actin
Myosin heads
Events of muscle contraction
1 Nerve impulse reaches presynaptic bulb and and calcium diffuses in
2 calcium causes vesicle with acetylcholine to fuse with the membrane and diffuse across synaptic cleft to the muscle fibre binding to receptors on sarcolemma
3 Na+ channels open in sarcolemma beginning action potential
4 action potential spreads across surface and down t tubules
5 calcium channels in sarcoplasmic reticulum open releasing calcium ions into sr
6 calcium bind to troponin and tropomyosin uncover myosin binding sites
7 myosin heads bind and and change their angle pulling on the actin to shorten muscle aka power stroke
8 atp is required to detach myosin from actin and cock the heads back
9 z lines move towards each other and each sarcomere shortens by about 10nm
10 process repeats until the signal from the nerve stops and calcium ions are pumped back
Striated muscle
Muscle in skeletal tissue. Muscle have regular striations seen under light microscope
Sarcolemma
The cell surface membrane of a muscle fibre
Sarcoplasm
Cytoplasm of muscle cell
Sarcolemma deep unfolding a are know as
Transverse system tubules or T-tubules for short
What pumps do the membranes of the sr have
Protein lumps to transport calcium into the lumen of the sr
The Sarcoplasm contains a lot of which organelles and why
Mitochondria packed tightly beteen myofibrils to carry out aerobic respiration generating ATP for muscle contraction
Myofibril
Cylindrical bundle of thick and thin filaments inside a muscle fibrr
Striated, cardiac and smooth muscle appearance
Stripes and regular intervals, stripes at regular intervals and no stirations
Cell structure of striated, cardiac and smooth muscle
Multinucleate, uninucleate cells joined by intercalate discs and uninucleate cells
Are smooth muscle proteins organised into myofibrils
No
Distribution of of striated, cardiac and smooth muscle in body
Muscles stretched to skeleton, heart and tubular structures like blood vessels and fallopian tubes
Control of of striated, cardiac and smooth muscle
Neurogenic myogenic and neurogenic
What is myosin
A fibrous protein with a globular head
What are the names of the chains twisted together and twisted around actin
Tropomyosin and troponin
Which protein wrapped around actin is fibrous
Tropomyosin
Where does calcium bind to
Troponin
What is the sliding filament model
Mechanism of muscle contraction. The sarcomeres in each myofibrils get shorted as the z discs are pulled close together
What happens when calcium ions bind to troponin
They change shape and both troponin and Tropomyosin molecules move to a different position on the thin filament exposing myosin binding sites on the actin
What happens when myosin heads move
They pull the actin filaments along towards the centre of the sarcomere
What happens after actin filaments are pulled towards centre of sarcomere
The heads hydrolyse ATP molecules providing enough energy to let go of the actin
What happens when head lets go of actin
Heads move back to previous position and bind to next site
parts of nervous vs endocrine system
Brain, spinal chord, neurones vs glands
Type of messengers nervous vs endocrine system
electrical impulses vs hormones
Method of transmission of nervous vs endocrine system
Neurones vs blood
effectors nervous vs endocrine system
muscles/glands vs target cells in specific tissues
speed of transmission nervous vs endocrine system
very fast vs slower
duration of effect nervous vs endocrine system
short until electrical impulses stop vs longer until hormone is broken down
