Module 8: Non-Infectious Disease and Disorder Flashcards
Why is homeostasis important?
To maintain proper functioning of enzymes
What systems are involved in homeostasis?
The hormonal system and nervous system
What are the two main components of the negative feedback loop?
Detecting change or the stimulus
Counteracting the change
What systems coordinate the negative feedback loop?
Nervous system or the endocrine system
What is the hypothalmus?
A part in the brain which is an important control centre
What are the effectors when there is an increased body temp?
Blood vessels, sweat glands, cells
What are the responses to increased body temp?
Blood vessels dilate
Sweat glands secret sweat evaporation leads to heat loss
Metabolic rate of cells decreases
What are effectors when there is a decreased body temp?
Blood vessels
Muscles
Cells
Hair erector cells
What are the responses to decreased body temp?
Blood vessels constrict
Muscles cause shivering
Metabolic rate of cells increase
Erect hair traps air
What are receptors responsible for?
Detecting stimuli
What do thermoreceptors detect?
Change of heat
What do chemoreceptors detect?
Concentration of certain chemicals
What do osmoreceptors detect?
Osmotic pressure
What are the two parts of the nervous system?
The central nervous system
The peripheral nervous system
What is the CNS composed of?
Brain and spinal cord
What is the PNS composed of?
All other nerves in body
How are messages transmitted by the nervous system?
In the form of electrochemical impulses
What is the cell body of a neuron?
Contains the nucleus
What are dendrites in neurons?
Fine branches which conduct nerve pulses towards cell body
What are axons in neurons?
Long extension which conduct messages away from cell body
What are sensory neurons?
Neurons which carry messages from sensory cells
What are motor neurons?
Neurons which transfer messages to muscles or glands
What are interneurons?
The link between sensory and motor neurons
What is the synapse?
A small gap between neurons
What are nerves?
A bundle of neurons gathered together by fibres
How are messages transmitted in nerves?
Electrochemical impulses
What is action potential?
Change in electrical potential during electrochemical impulses
What happens during action potential?
There is a change in concentration of ions on either side of the membrane
When is a neuron at rest?
When no message is being transmitted
What is the resting membrane potential?
-70mV
What is the ion arrangement around neurons when at rest?
Lots of Na+ ions outside and little K+ ions inside
What is the membrane called at rest?
Polarised
What happens when stimulus is detected?
Sodium channels open and Na+ move in to neuron reducing overall negative charge
What is the threshold value?
-55mV
What happens if threshold value is met?
Na+ ions will continue to move in regardless of stimulus
What happens when Na+ moves into the neuron?
Causes inside to be more positive known as depolarisation
What happens during depolarisation?
Potassium channels also open allowing K+ ions to move out known as repolarisation
How long are potassium channels open for?
Slightly longer than sodium channels
What does action potential trigger?
The release of neurontransmitters
What are neurontransmitters and what do they do?
They are chemicals that move across the synapse initiating an action potential
What type of matter is the brain and spinal cord made up of?
White and grey matter
What does grey matter mainly consist of?
Neuron cell bodies
What does white matter mainly consist of?
Nerve fibres
Where is grey matter in the brain?
On the outside
Where is grey matter in the spinal cord?
In the centre
What is the brain?
Main control centre of the body
What does the spinal cord do?
Provides link between the peripheral nervous system and brain and coordinates reflex actions
What does the endocrine system use?
Hormones which are secreted by endocrine glands
How are hormones transported in the body?
Via the blood
What do hormones do?
They influence activity of particular enzymes
What is the pancrease made up of?
Structures called pancreatic islets
What do the pancreatic islets do?
Produce hormones insulin and glucagon
What type of cells are in pancreatic islet cells?
Alpha and beta cells
What do beta cells do?
Detect high levels of glucose and produce insulin
What does insulin do?
Allows glucose to be removed from the blood by forming glycogen
What do alpha cells do?
Detect low levels of glucose and produce glucagon
What does glucagon do?
Stimulates the production of glucose by breaking down glycogen
What are endotherms?
Organisms which can maintain their body temp
What behavioural adaptions do endotherms have to maintain body temp?
They alter or move the position of their body to increase or decrease temp
What are some examples of behavioural adaptions of endotherms to maintain body temp?
Penguins huddle together when cold or go in water when hot
Nocturnal activity prevents exposure to heat of the day
What structural adaptions do endotherms have to maintain body temp?
Insulation like hair, feather, fur and fat prevent heat loss
Surface area such as small or big ears
What physiological adaptions do endotherms have to maintain body temp?
Metabolic activity can be altered
Shivering
Hibernation
Sweating or panting
What is transpiration?
Evaporation of water from the stomata
What are xerophytes?
Plants that live in arid conditions
What are 8 adaptations of xerophytes?
Shiny wax and thick leathery cuticles
White hair on leaves
Orientation of leaves
Reduced surface area
No leaves
Regulating open and close of stomata
Fleshy stems and leaves
Woody fruits
What are non-infectious diseases?
Disease which is not caused by pathogens and are not contagious
How much do non-infectious diseases account for deaths in aus?
Account for the four leading causes of death
What are genetic diseases caused by?
Mutations of the genes or chromosomes or abnormal cell division
What causes single gene abnormalities?
When a person inherits mutated genes from parents
What diseases does single gene abnormalities cause?
Cystic fibrosis, albinism and sickle cell anaemia
What causes cystic fibrosis?
Mutation of the CFTR
How does the mutation of CFTR cause cystic fibrosis?
The faulty gene changes the protein which regulates NaCl movement
What does cystic fibrosis cause and affect?
Causes abnormally thick mucus which affects the respiratory, digestive and reproductive system
What are the two types of chromosomal abnormalities?
Incorrect number of chromosomes and a change to the chromosome
What causes an incorrect number of chromosomes?
Non-disjunction
Trisomy
Monosmy
What is non-disjunction?
Incorrect seperation of chromosomes
What is trisomy?
One extra chromosome with a normal pair
What is monosmy?
When one member of chromosome pair is gone
What happens to babies with monosmy or trisomy?
They will have a syndrome which is a group of symptoms which relate to a disease
What is deletion of a chromosome?
When a chromosome breaks and some of it is deleted
What is translocation?
When a section of a chromosome moves to join another
What is down syndrome?
The most common trisomy syndrome
What causes down syndrome?
An extra chromosome 21
What are the characteristic facial features of down syndrome?
Small flat skull, almond shaped eyes and small ears that fold over
What are the impacts of down sydrome?
Intellectual disability and heart defects
What are lifestyle diseases?
Those that directly arise from the way people live their life
What are the four most common lifestyle diseases?
Cardiovascular disease
Diabetes
Cancers
Chronic lung disease
What are the risk factors of lifestyle diseases?
Tobacco use, unhealthy diet, physical inactivity, harmful use of alcohol
What physical factors can cause disease?
Exposure to UV and radiation
What is the risk of exposure to some chemicals?
Exposure to some chemicals increase the chance of developing a disease
What can exposure to asbestos lead to?
Lung cancer
What are the causes of nutritional diseases?
Diets lacking the proper balance
What are the two types of malnutrition?
Undernutrition and overnutrition
What does lack of protein cause?
Kwashiorkor disease
What are the symptoms of kwashiorkor disease?
Swollen belly and failure to grow
What does lack of vitamin A cause?
Blindness in children
What does lack of vitamin D cause?
Rickets in children
What are the symptoms of rickets?
Defective calcification of bones
Bowed legs
What does lack of vitamin C cause?
Scurvy
What are the symptoms of scurvy?
Poor wound healing
Bones that do not grow
Spontaneous haemorrhaging
What does lack of iron cause?
Anaemia
What are the symptoms of anaemia?
Pale skin
Weakness
Unusual tiredness
What is anorexia nervosa?
It is the intense fear of gaining weight
What are the symptoms of anorexia nervosa?
Excessive weight loss
Tiredness
Aneamia
What is bulmia nervosa?
It is similar to anorexia but it entails binge eating and then purging via vomiting
What is the most common type of overnutrition?
Obesity
What are the symptoms of obesity?
Weight gain
Increased blood pressure
Type two diabetes
Arthritis
When does cancer occur?
When abnormal cells divide in an uncontrollable way
What control cell devision?
DNA repair genes, proto-oncogenes, tumor suppressor genes
What are DNA repair genes responsible for?
Stopping the cell cycle and repairing damaged regions of DNA
What are proto-oncogenes responsible for?
Stimulating cell growth and mitosis
What does mutation of proto-oncogenes cause?
Lead to oncogenes that cause uncontrolled cell production and prevent cell death
What are tumor suppressor genes responsible for?
Slowing down or stopping cell growth and mitosis and inducing cell death
What is a benign tumor?
Not a cancer and cells remain within a boundary
What is a malignant tumor?
Contain abnormal cancerous cells which are not confined by a boundary and redirect the nutrients to themselves
What is metastasis?
The spread of a tumor in the body
What is a sarcoma?
Cancer in muscle, bone or blood vessels
What is a carcinoma?
Cancer in skin or tissue that lines organs
What is lymphoma?
Caner in the lymphatic system
What is leukaemia?
Cancer in bone marrow and other blood forming tissue
What are central nervous system cancers?
Cancers wich begin in the brain or spinal cord
What are 7 causes of cancer?
Smoking
Excessive alcohol consumption
Lack of physical activity
Exposure to radiation
Exposure to chemicals
Contracting some viruses like HPV
Inheriting mutated genes
What is melenoma?
The uncontrolled division of melanocytes
What are the risk factors of melenoma?
Exposure to UV
Fair complexion
Severe sunburn
Male gender
What is mortality rates?
The number of deaths due to the disease in a time period
How do you calculate mortality rates?
Number of deaths / population
What is epidemiology?
The study of patterns of disease in population
What is epidemiology used for?
To determine the potential cause of disease and find out which population are affected
What is the treatment for melanoma when detected early?
Surgery
What is the treatment for more advanced cases of melanoma?
Radiation
Chemotherapy
Targeted therapies
Immunotherapy
What are descriptive studies?
The first type of study conducted when investigating disease
What do descriptive studies provide?
Information about patterns of the disease
What are analytical studies?
Collection of data which is statistically analysed to test hypothesis
What type of data is collected in analytical studies?
Morbidity, mortality, incidence and prevalence
What are the two types of analytical studies?
Case control and cohort studies
What are case control studies?
Compare people with disease (case) to people without (control)
What are cohort studies?
Studying two or more similar groups without disease, one group exposed to possible cause other is not
What are intervention studies?
Used to test effectiveness of a treatment or health campaign
What is an experimental study?
When one group receives the trial drug and the other receives a placebo
What is a quasi - experimental study?
When a random trial is impossible so researchers choose the subjects
What are the three criteria any intervention study should meet?
Conducted over a long period of time
Study of a large sample size (thousand)
Represent the wider population
What are random errors?
Unpredictable and inconsistent effect on measurement
What can be done to reduce random erros?
The study of large sample sizes
What is systemic error?
Bias which causes consistent deviation in measurment
What are public health campaigns used for?
To provide information to educate the population about risk factors to minimise exposure to them
What is an example of a public health campaign?
‘Slip, Slop, Slap, Seek, Slide’
What are legislations?
Laws which minimise risk factors
What is PGT?
Pre-implantation genetic testing
What is the process of PGT?
Cycle of IVF
Eggs directly fertilised with injection of sperm
Embryos grown for three days
One cell removed and tested
Embryos free of gene retained rest destroyed or kept for research
Day 5 embryos implanted
Pregnancy develops normally
What is golden rice?
Rice which has genetically been engineered to produce beta-carotene
What does the body use beta-carotene for?
To produce vitamin A
What is the pinna?
Fleshy part of the outer ear, directs sound to auditory canal
What is the auditory canal?
Tube from outer to middle ear
What is the tympanic membrane?
Taught membrane, transmits vibrations to middle ear
What is the ear ossicle?
Three small bones, magnify vibrations and transfers to oval window
What is the oval window?
Membrane separating middle ear from fluid filled inner ear
What is the round window?
Membrane at the base of the cochlea, vibrates in conjunction with oval
What is the cochlea?
Snail shaped, holds fluid which helps convert vibrations into nervous signals
What is the organ of corti?
Receptor cells in the cochlea converting vibrations into electrical impulses
What is the auditory nerve?
The nerve which carries electrical impulses to the brain
Where are high pitches detected in the cochlea?
At the base
Where are low pitches detected in the cochlea?
At the apex
When does conductive hearing loss occur?
When there is a problem with mechanical conduction, inner and middle ear
What are some causes of conductive hearing loss?
Perforated eardrum, infection and damage to ossicles
What is usually affected with conductive hearing loss?
The loudness of sound
When does sensorineural hearing loss occur?
When there is damage to the inner ear
What are some causes of sensorineural hearing loss?
Excessive noise exposure, heredity, infection, tumors and ageing
What is impacted with sensorineural hearing loss?
Prevents kinetic energy being transformed into electrical impulses
How does a hearing aid work?
Magnify sound vibrations
What can hearing aids assist with?
Conductive and sensorineural hearing loss
Where is a hearing aid worn?
Behind or inside the ear or in frames of glasses
How does a bone conduction implant work?
Microphone detects sound which is transformed into vibration directed through bone to the cochlea
What can bone conduction implants assist with?
Conductive hearing loss
Where is a bone conduction implant worn?
On the side of the head behind the ear
How does a cochlear implant work?
An external speech processor and transmitter coil is attached to an electrode array implanted in the cochlea
What can cochlear implants assist with?
Sensorineural hearing loss
Where is a cochlear implant worn?
On the side of the head behind the ear
What is the conjunctiva?
Clear mucos membrane that provides protection and lubrication
What is the cornea?
Clear layers with nerve endings covering the iris and pupil
What is the sclera?
Tough protective coating surrounding the eye
What is the choroid?
Vascular tissue that reduces scattering or reflection of light
What is the retina?
Light sensitive tissue that captures incoming photons and transmits them
What is the iris?
Pigmented circular structure that controls the size of the pupil
What is the lens?
Crystalline biconvex structure that changes shape to refract light
What is the aqueous humor?
Clear gel between the lens and cornea that provides nutrients and support
What is the virtueous humor?
Clear gel between the retina and lens that provides nutrients and support
What is the ciliary body?
Muscle that produces fluid in eyes called aqueous humor
What is the suspensory ligament?
Ring like fibrous membrane that control size of lens
What is the optic nerve?
Neurons that carries messages from receptors to brain
What is the fovea?
Area in back of eye with high concentration of cones responsible for high acuity vision
What is accommodation?
The way the lens curves to focus objects
How does the curvature of the lens impact refractive power in eyes?
The greater the curvature the greater the refractive lens
What type of curvature is required for focus on close objects?
Increased curvature
What type of curvature is required for focus on far objects?
Lengthening of lens
Where are rods and cones located in the eyes?
Retina
What do rods and cones do?
Convert light energy into electrochemical impulses
About how many rod cells are there in th eye?
125 million
About how many cone cells are there in the eye?
6-7 million
What do rods do?
Cannot detect colour and have very high light sensitivity
What are in cones?
Three types of iodopsins
What are iodopsins?
Sensors in cones which can detect red, green and blue wave lengths
What causes myopia?
Eyeball too elongated and refractive power of cornea may be too strong
What is hyperopia?
Long sightedness
What causes hyperopia?
Eyeball is too rounded and the lens is too flat and the refractive power of the cornea is too weak
What are cataracts?
Clouding of the lens
What are the impacts of cataracts?
Reduces transmission of light and blurred vision both near and far
What is macular degeneration?
Degeneration of cells beneath the retina
What are the impacts of macular degeneration?
Central vision is affected but peripheral vision is unaffected
What type of lenses corrects myopia?
Concave lenses
What type of lenses corrects hyperopia?
Convex lenses
What is cataract surgery?
A surgery that corrects cataracts by replacing the cloudy lens with an artificial lens
How does cataract surgery work?
The cloudy lens is broken down and suctioned out
What is LASIK surgery?
A surgery which can improve myopia and hyperopia
What occurs during kidney damage?
Nephrons are damaged meaning that filtration, reabsorption and secretion can not occur
What are some causes that lead to kidney damage?
Diabetes, high blood pressure, kidney infections and cancer
How does haemodialysis work?
Blood is removed from body and blood is pushed through a filter
How does peritoneal dialysis work?
Dialysate put in abdomen of patient and the peritoneum filters out the waste
How is waste removed from blood during dialysis?
It moves from blood into dialysate by diffusion
What are three ways in which educational programs can be effective in reducing non-infectious diseases?
- Promoting healthy behaviour
- Increased awareness of risks of environment exposure
- Increased participation in screening
What is the ciliary muscle?
Muscle which contract or relax to modify the shape of the lens
What is the positive feedback concept?
Positive feedback strengthens the original stimuli
Which factors affect homeostasis?
Internal environment
Where is carbon dioxide carried in the blood?
70% forms HCO3 - and travels in the plasma
23% combines with haemoglobin
7% directly dissolves in plasma
What is the process that occurs in glomerulus?
Filtration
