The control and regulatory system Flashcards
what does the nervous system do
- co-ordinates voluntary and involuntary actions through a network of nerves linking the brain to different parts of the body
what are the two parts of the nervous system
- central nervous system (CNS) - brain and spinal cord
- peripheral nervous system (PNS) - network of nerves
what does the central nervous system (CNS) do
- take in sensory information
- process information
- send out motor signals to complete tasks (responses)
what does the peripheral nervous system do and contain?
- sensory nerves (transmit sensation, pain and touch)
- motor nerves (control muscles)
- autonomic nerves (regulate automatic functions of the body e.g. blood pressure and bladder function)
- somatic nervous system and autonomic nervous system
what does the somatic nervous system contain and what do they do
- voluntary nerves
- motor nerve (send messages to our muscles)
- sensory nerves (send messages from our senses)
what does the autonomic nervous system contain and what do they do
- involuntary nerves
- sympathetic nervous system (activate functions needed for survival and prepare for action)
- parasympathetic nervous system (return body to normal resting state)
how do neurons work
- neurons connect to the brain via the spinal cord and deliver electrical impulses that stimulate muscles or sensory organs
- neurones connect to one another to form a ‘chain’ to reach all parts of the body
- neurons deliver impulses along length of neurons to cause action
what are the two halves of the brain called
cerebral hemispheres
what connects the two halves of the brain
bridge of nerve tissue called corpus callosum that enables communication between the two halves
what is the left side of the brain dominant for
language
what is the right side of the brain dominant for
- emotional processes
- some elements of language such as intonation and emphasis
which side of the body do each side of the brain control
each side of the brain controls the opposite side of the body
parts of the brain
- meninges
- corpus callosum
- frontal lobes
- hypothalamus
- medulla
- cerebellum
- cerebral cortex
function of the meninges
- protects the brain
- they are tough and comprise of three layers
- surround the spinal cord and act as a barrier to protect from infection
function of the corpus callosum
- bridge of nerve tissue that connects two halves of the brain and enables to communicate
- this is where the nerves happen that allow the left side of the brain to control right side of the body
function of the frontal lobes
- part is responsible for higher level mental processes
- it can be damaged more easily
- damage here will alter ability and personality
function of the hypothalamus
- regulates temperature, appetite and thirst
- controls a number of hormone which promt secual development and reproduction
- links to pituitary gland
function of medulla
automatically controls and regulates vital processes such as swallowing, heart rhythm, and breathing
function of cerebellum
control messages to muscles to control movement
- store memory here that allow us to rember fine movements
- indeed in control of muscles to maintain balance
- alcohol affects this part (why people are wobbly while drunk)
function of cerebral cortex
sensory information is received here from various areas of body and relayed to appropriate muscles
how is homeostasis continued in the body
the parasympathetic nervous system and the sympathetic nervous system work together to maintain the body at an optimum level of functioning
what is the function of the cell body in a neuron
it contains the nucelus and therefore the chromosomes
what is the function of the dentrites in a neuron
extend from the cell body
they carry electrical impulses from other neurons towards the cell body
what is the function of the axon in the neuron
it is an extension of the neuron
it carries the electrical impulses away from the brain and towards the rest of the body
it is covered in the mylin sheath
what is the function of the mylin sheath
to increase the speed at which the electrical impulses travel along the axon
what are the gaps in the mylin sheath called
nodes of ranvier
what is a synapse
the small gap between neruons which the signal needs to cross
how do neurons transmit signals over the synapse
- the signal crosses the synapse through chemicals called neurotransmitters
- neurotransmitters are released from the axon terminals and they diffuse across the synapse
- once they reach the other neuron, the neurotransmitters bind to a receptor on the dendrites of the next neuron
what are the two types of stroke
- ischaemic
- haemorrahagic
what causes an ischaemic stroke
clots blocking the blood vessel in the brain, depriving an area of the brain of oxygen and nutrients and therefore causing the cells to die
what causes a hemorrhagic stroke
blood vessel in brain ruptures.
the escaping blood is confined by the skull, pressing on brain and causing a build up of pressure
Damaging the cells
what is a transient ishaemic attack
when a blockage clears itself
causes of strokes
- blockage in the blood flow to the brain
- build up of cholesterol that has made its way to the brain
risk factors of strokes
- family history
- above 55 years of age
- male
- high salt intake
- smoking
- heavy alchohol drinking
- oral birth pill
- sickle cell disease
- African American
what is the sympathetic nervous system responsible for
increases tbe activity of the body’s organs e.g. prepare for fight or flight
what is the parasympathetic nervous system responsible for
reduce activity of the body’s organs e.g. when we calm down after fight or flight
prevention of multiple sclerosis
- stop smoking
- limit salt intake
- avoid alcohol
- diet free from cholesterol and fats
- plenty of fruit and veg
- exercise regularly
- maintain healthy weight
why is multiple sclerosis so difficult to diagnose
it has similar symptoms ro other diseases
it doesn’t have a certain cause
what are the two types of diabetes
type 1 - early onset
type 11 - late onset
what is type 1 diabetes
- thought to be an autoimmune disease where the pancreas lining is destroyed during childhood
- it occurs when insulin isn’t produced so individuals rely on insulin injections
what is type 11 diabetes
- linked with the intake of carbohydrates and fats
- occur when pancreas stops making insulin or body’s cells lose ability to recognise or respond to insulin
- therefore injections won’t help
effects of diabetes
- blood sugar levels rise
- glucose leaves body as urine
- drop in blood sugar leads to hypoglycema, fainting, coma or death
- stroke, heart problems, kidney disease, eye problems, loss of skin sensitivity
- loss of skin sensitivity might lead to infection/ amputation of mainly the lower leg, but sometimes all 4 limbs might be lost.
what is the endocrine system
series of glands that produce hormones with a specific function
how do hormones travel throughout the body
blood stream
what functions does the endocrine system do
- metabolism
- growth
- reproduction
- sleep
- mood
what are the glands in the endocrine system
- pituitary gland
- adrenal gland
- pancreas
- thyroid
- reproductive gland (testes/ovaries)
what hormone does the adrenal gland produce
adrenaline
what hormone does the pancreas produce
insulin and glucagon
what hormone does the thyroid produce
thyroxin and calcitonin
what hormones does the pituitary gland produce
Somatotrophin
LH/FSH
Oxytocin
ADH
Prolactin
what hormone does the testes produce
testosterone
what hormone does the ovaries produce
oestrogen and progesterone
where is the adrenal gland located
on top of each kidney
what does adrenaline do
prepares the body for action
It is released as a response to a threat
It increases heart rate and breathing rate
what does the pancreas do
controls glucose (blood sugar) levels
what does insulin do
lowers blood glucose levels
what does glucagon do
raise blood glucose levels
what does thyroxin do
affects growth and sustains metabolism
what does calcitonin do
regulates calcium absorption and use
what does pituitary gland do
some of the hormones it releases tells the body what to do and some tell other glands to release their own hormones
what does somatotrophin do
growth hormone promoting bone growth
what does LH/FSH do
controls your menstrual cycle
what does oxytocin do
initiates contraction of your uterus
what does ADH do
triggers uptake of water from your kidney
what does prolactin do
initiates production of breast milk
what does testosterone do
affects sexual development, growth of facial hair, changes at puberty and sperm production
what does oestrogen and progesterone do
control breast growth and reproductive functions such as menstruation and pregnancy
how is a stroke diagnosed at a hospital?
brain CT scan can show bleeding or damage to the brain which causes a stroke
how is multiple sclerosis diagnosed
no specific test
physical exam
MRI scan
how is diabetes diagnosed
Blood test
Urine test
what are the jobs of the kidney
Filter blood
Regulate levels of ions and water etc in the blood
Remove waste
what is the main waste product from the kidney
Urea
what process creates urea
Deamination
how do we lose most water
from urea
why do we need to Regulate our water levels
it can damage cells if its too high or too low
what happens to cells if water is too high
cells can burst
what happens to cells if water is too low
they can shrink
how many nephrons in body
1,000,000
what are absorbed in the tubule
water
amino acids
glucose
urea
what is the name of the process that absorbs things in the tubules
filtration
what is reabsorbed into the blood after filtration
all glucose and some water
what hormone is released when our water levels are too low
ADH
what does ADH tell the kidneys to do
tell tubules to absorb more water to get our water levels up
what happens if there is extra water in our body
there is more urea
how is the kidneys an example of negative feedback
body is constantly readjusting levels
where does blood enter the kidneys
renal arteries
how does blood leave the kidneys
renal veins
where is urine stored
bladder
what is filtration
when liquid is forced from glomerular into Bowman’s capsule
what is the process of reabsorption called
Selective reabsorption
how is urea formed
- created when excess amino acids are broken down by liver to be disposed of
- liver removes nitrogen, creating ammonia which is then turned into urea by the liver
- this passes into blood and to the kidneys where its filtered
what is osmoregulation
regulation of water level
what happens if there is a loss of water
- hypothalamus detects if there isn’t enough water in blood
- it sends impulses to pituitary gland to release ADH
what happens if there is too much water
- hypothalamus isn’t stimulated, pituitary gland doesn’t release ADH and water is passed to the bladder
what happens in negative feedback in the body
conditions change from ideal point and system returns conditions to ideal point
what does the liver do
Produce bile
Store nutrients and supply to cells
what is assimilation
the body supplying nutrients to the body’s cells
what is the malfunction of the liver
Cirrhosis
what is cirrhosis
Inflammation and scarring of the liver
causes of cirrhosis
Excessive alcohol consumption
Prolonged viral attack
symptoms of cirrhosis
Jaundice
Ascites
Easy brusing
Hepatic encephalopathy
how is cirrhosis diagnosed
biopsy
lab test
what are the treatments for cirrhosis
Find the underlying cause
Liver transplant
what is the function of the liver
break down amino acids and form urea
what is deamination
removal of nitrogen in amino acids
how is liver cirrhosis formed
- if we don’t give our liver a break from alcohol, liver cells can be destroyed by continuous alcohol abuse
- too much scarring prevents liver from functioning and can lead to liver failure
- only liver transplant can prevent death
what is homeostasis
maintenance of ideal or optimal conditions in the body
function of the glomerulus
filters the blood and removes water, glucose, salts and waste urea from it.
function of bowmans capsule
removes glucose, salt, water, amino acids and urea out of the blood into the nephron
function of nephron
filtration, reabsorption, secretion, and excretion
function of Loop of Henle
recovery of water and sodium chloride from urine
where does nephrotic syndrome affect
normally affects both kidneys
how does nephrotic syndrome occur
- the immune system overreacts to a common infection and begins to attack parts of the kidney
what is the malfunction of the kidneys
Nephrotic Syndrome
what part of the kidney gets most affected by nephrotic syndrome
the basement membrane of the glomerular capillaries
what happens after the kidneys are damaged in nephrotic syndrome
- the blood proteins are lost in urine as kidneys are so damaged
- albumin gets lost meaning fluid will collect in tissues, causing the body to swell which strains the heart and lungs
- anitbodies are also lost meaning the body might not be able to fight off infections
- blood clotting proteins are also lost, resulting in easy brusing
how is nephrotic syndrome monitored
treating any medical conditions that might be causing nephrotic syndrome
Medications or changes in diet to help control your signs and symptoms
how is nephrotic syndrome diagnosed
- urine tests
- blood tests
- kidney biopsy
what are the treatments for nephrotic syndrome
- medications to control immune system
- if no response to medication, then a transplant is needed
what are the symptoms of nephrotic syndrome
- severe welling, particularly around eyes, ankles and feet
- high cholesterol
- very high protein in urine
- low protein in body
what are causes of nephrotic syndrome
- inside of kidney becomes scarred
- inflammation inside kidney
- lupus
- an infection (e.g HIV)
- diabetes
- sickle cell anaemia
