MBP Flashcards
What does respiratory airway include?
Nasal passage, pharynx, larynx,trachea,bronchi,bronchioles
bronchioles have alveoli at end in grapelike arrangement(exchange of co2 and o2)
ATP
Carbon dioxide generated due to supply of energy
Mitochondria job
supplies cell with energy for metabolism and muscle contraction
mitochondria structure
inner and outer membrane, outer membrane forms cristae, have own dna
alveoli
next to alveoli rich blood supply, close to sacs this means less diffusion distance
Pharynx structure
split into 2 tube, oesophagus and trachea, trachea lined with ciliated epithelium and cilia moves in wave towards pharynx.
epithileum secrete thick mucus to trap dust and move down towards oesophagus
macrophage job
macrophage in lung trap particulate matter by phagocytosis
they migrate up trachea and deposit material into oesphagus
chest cavity
diaphragm allow contraction and relaxation of lungs which allows us to breathe in and out
pleural cavity
liquid between chest wall and lungs
inhaling
diaphragm contracts. chest wall moves out
volume in chest cavity increases
reduction in fluid pressure of pleural cavity
pressure in lungs lower than atmospheric pressure therefore air moves into lungs down conc gradient
exhaling
diaphragm relax, chest wall move inward
increase in fluid pressure of pleural cavity
increase in pressure insie lungs above atmospheric pressure so air moves out lungs
residual volume
air left in our lungs after we breave out forcefully
expiratory reserve volume
additional amount of air that can be expired from lungs after normal expiration
tidal volume
amount of air that moves in or out of lungs with each respiratory cycle (500ml)
inspirtory reserve volume
amount of air that can be forcefully inhaled after normal tidal volume (2500-3500ml)
how much oxygen do we inhale and how is it used
1000ml
800ml expired into blood
200ml absorbed into alveoli
heart pumps blood and 200ml/min of oxygen transferred to organs and tissue
how is oxygen transported
passive diffusion, high to low conc, molecules in closed container exert pressure against walls
what happens when oxygen reaches blood
10% dissolved into blood plasma
most o2 binds with haemoglobin
around 5mil rbc per ml of blood
30% of cell weight taken up by haemoglobin
remainder is absorbed by rbc
hyperventilation
hella o2 available
hypoventilation
small amount of o2 available
rbc structure
biconcave structure, reduces pressure inside
in middle 1 micron at edge 2 microns(biconcave)
whole width of rbc 7.5microns
how does PH affect saturation
High pH stabilises saturation at low pressure
Low pH stabilises saturation at high pressure as haemoglobin has less affinity for o2 at low ph.
what will less acid in lungs cause
encourage binding of oxygen to oxygen
what does more acid in capillaries cause
encourage release of oxygen from haemoglobin to tissues
carbon dixoide affinity
co2 has less affinity for haemoglobin
how is carbonic acid formed
co2 and water
how is co2 carried
in form of bicarbonate ion in blood
co2 removal
to be removed co2 needs be in lungs.
co2 which is released 8% us dissolved in plasma,25% of co2 dissolved in haemoglobin,67% dissolved into carbonic acid
how is carbonic acid formed
carbonate ions and hydrogen ions combining
number of genes and pairs
46,23
karotype?
photo of chromosomes used to understnad shape size and number and charactersitcs
function of reproductive system
allows transfer of genes from parents to child
protects embryo containing parental genes
where is sperm produced
seminiferous tubule
is sperm in middle mature or no
mature
what releases sperm
vas deferens
how is sperm formed and where
in semineferous tubule, spermatogonium at periphery(immature) this then becomes speratocyte then spermatid then sperm
meiosis in sperm
number of chromosomes halved during formation of sperm
each sperm contains one full set of chromosomes
meiosis occurs during spermatocyte formation and egg developiment
what do mature sperm cells have
longer tails
structure of sperm
top has head which contains nucleus and releases enzymes to burrow into egg,takes one sperm to fetilise egg
have contractile filaments
tails allow fast swimming and tail has mitochondria around it to provide energy, mito packed together closely
final developemtn of sperm
stored in vas deferens
stored outside body in sac like structure
secretion is from seminle vesicle and secretion called fructose which allows sperm to stay alive
hormones
substance released from gland into blood which has specific effect on target cells
sex hormones in male
testosterone
gonadotrophin
FSH
LH
Testosterone
controls manufacture of sperm
helps release of sperm
maintains sex drive
determiines sexual characteristics like deep voice and beard
how is testosterone controlled
controlled by hypothalamus via pituitary gland
hypothalmus release fsh and lh which travel to pituitary
here gates open allowing these to be released into blood
in blood testosterone released
too much testosterone will prevent hypothalmus from releasing fsh and lh
Ovaries
2 ovaries in body cavity
main function produce eggs
secret female sex hormones oestegoen and progestrone
at birth ovary contains 400000 egg follicles and only 400 mature in female life
developemnt of egg
primodial are follicles which are potential egg formations
growing follicle
mature follicle with egg
degenerating follicle
primary follicle
oocyte
granulosa cells
zona pellucida
Ovulation
mature egg pushes way out ovary
space filled with partially clotted fluid first then follicle egg will enlarge and fill up hole which is called corpus luteum
corpus luteum is important if egg fertilised as produces female hormones important for pregnancy
how is ovulation controlled
overall controlled by hypothalmus
5-10 days after last period level of oestrogen rises which stimulates growth muscles in uterus walls and epithelium of uterus so wall thicking for fertilised embryo
ovulation occus 15 days after last period which induced by high level of LH
after ovulation progesterone level rises which stimulates epithelium to prodcue secretory tissue and provide stable environemnt for fertilised egg
this lasts between 15th and 28th day
when no embryo implanted corpus luteum degenerates and levels of hormes fall which cause constriction of vblood vessel of uterus and lining removed
bleeding occurs as capillary walls weakened during process
fertilisation
sperm penetrates egg by releasing enzymes from cap at tip of head
sperm enter cytoplasm of egg and loses tail
fertilisation occurs when nuclei of sperm and egg unite
fetilised egg will move down uterus and divide to form ball of cells
placenta
critical in development of embryo
made of cells of mother and embryo
enables exchange of materials to take place
events of pregnancy
sign of pregnancy is hormone change
chronic gonodatrophin allows attachment of embryo to female body
oestrogen and progestorone increases and then decreases as soon as childbirth
whaat does nervous system consist of
brain
spinal cord
peripheral nerves
how many nerve cells in brain
150 bill
development of nervous system
develops from narrow strip of cells out side of embryo
run from head to tail
cells are ectoderm cells and during developments they will sink gradually into embryo
strip of ectoderm cells will sink to form neural groove which have nerual plates along it
what is neural tube
neural ectoderm sinks further to form neural tube
its has horse shoe shape
edges of groove meet and fuse together and a tube of cells called neural tubes are formed.
tube surrounded by ectoderm and runs from head to tail of embryo
what will neural tube develop into
mostly spinal cord
upper part of tube will be sensory in function and fibres sent will be out to surface of skin
lower part will be devoted to motor fucntions and fibres sent out to muscles
at head end of tube what are 3 regions
forebrain
midbrain
hindbrain
what is cerebral spinal fluid
fluid that formed from neural tube expanding and its used to surround brain and protect it in skull
forebrain
develops into lateral ventricles which later form cerebral hemispheres
midbrain and hindbrain
midbrain forms 4 bumps callec colliculi which are important in vision and hearing
hindbrain develop into the pons which are swollen area of fibres and will commuicate with cerebellum
medulla contains various important parts that are need to keep body working
cerebral hemispheres
they have dramatic growth and become dominant feature of brain
bend over to fill availble space
axis of neural tube in spinal cord is vertical but in brain is horizontal
what is dura matter
thick membrane that protects mature brain
any infection in this area can be very dangerous
cerebral hemispheres
dominant feature of brain and has many diff areas
lateral surface
frontal- responsible for complex movemnt and intellectual activity
motor-movemnt
somatosensory- sensations from skin
temporal-hearing emtion memory
occipital-vision
parietal-integrates sensory data
saggital surface
corpus callosum- integrates 2 hemispheres
thalamus- relay station for data entering brain
pituaitary gland- endocrine control
cerebellum-balance
pons-integrate cerebellum and cerebral cortex
medulla- respiration adn cardiac cycle
basal ganglia
controls movement
agnesis of corpus callosum
developmental abnormality
results in failure of corpus callosum to develop
lead to fatal changes in brain
pyramidal neurons
classic structure with branched dendrites and single long axon
dorsal root neuron
no neurons and single long axon
granule neurons
dendrites but short axon
bipolar neurons
single axon and dendrites
purkinje neurons
elaborate dendritic tree
allow multiple relay of impulses
visual pathway
eye
optic chiasm
lateral geniculate nucleus
visual cortex
brain lesion
means injury on brain
in brain large area of parietal cortex will be affected by brain haemorrhage
magneto encephalography
when subject look at visual stimulus and this generate electrical activity in brain and magnetic field around head will change
coloured areas show regions where magnetic field leaves and enters head
position emission tomography
radioactive tracer injected into patient
maximum radioactivtiy will correspond to brain activity
patient will be given task and PET will show which parts become stimulated
PET scan shows area damged by a stroke
classification of stimuli
physical effects include pressure and temp
sensations include softness,tickling and pain
vertical section of skin
made of epidermis, dermis, subcutaneous fat and seep fascia muscles
hair follicles lie deep in sebaceous glands which found in dermis
sensory endings where nerve fibres end
free nerve endings are not associated with special structure but encapsulated endings are associated with special structure
encapsulated endings
pacinian corpsucle has nerve ending thats shielded by layer of lamellae, these respond to change in pressure at surface of skin
meissners corpsucle is less shielded than pacinian
occur more closer to skin and more sensitive indicators of touch
unipolar neurons
skin receptors are specialised endings of unipolar neurons
they have few processes and convey info from skin to spinal cord
pathway to spinal cord
pacinian corpsucle in skin has long neuron which attached to neuron in dorsal root ganglion then flows into spinal cord
receptive fields for skin stimuli
touch sensations are quite large and overlapping
completely cover skin
hardly any part of our body which is unstable to experience touch sensations
temp sensations are spread out because temp of our body varies in diff places, some sensitive to hot some to cold
pain sensations have diff fields where sensation in core diff to peripheral.
pathway to brain from skin
first impulse sent from skin to spinal cord
then two relays occur first at medulla and second at thalamus
then impulse go to cortex to form sensations, somoatosensory cortex where skin sensation percieved
in first relay 2 nucleus are invovled the cuneate nuclues and gracile nucleus
relaays in brain sharpen image and remove noise
with relay the sensation more accurate
pain pathways
brain contains natural painkiller called endorphins and enkephalins
they discovered due to natural receptors to pain killin drugs like morphine
extreme pain result in release of enkephalins to block pain
as pain impilse travels up to cortex info is conveyed to central grey substance
this initiates impulse which carried to spinal cord and struck neurons to release enkephalins
this release the pain impulse travelling to spinal cord
