Module Eight - Non-infectious Disease and Disorders Flashcards
Homeostasis Causes and Effects Epidemiology Technologies and Disorders (121 cards)
1
Q
what is homeostasis?
A
maintenance by an organism of a relatively constantly internal state, regardless of external changes in the environment
2
Q
what is the purpose of homeostasis?
A
allows organisms to function at their optimal metabolic efficiency despite changes in the external environment
3
Q
why is homeostasis important?
A
it is essential that internal conditions be maintained in order for enzymes to perform at optimal metabolic efficiency
4
Q
which body systems are involved in homeostasis?
A
- nervous system
- endocrine system
5
Q
what does tolerance limits in homeostasis refer to?
A
the narrow range that variables that are maintained by homeostasis can be
6
Q
what is a set point in homeostasis?
A
the ideal/regular value for variables that are maintained by homeostasis
7
Q
what is the negative feedback system?
A
a self-regulating mechanism that maintains balance or homeostasis as a coordinated response or series of responses to a stimulus or stimuli
8
Q
what are the two main stages of homeostasis?
A
- detecting change
2. counteracting the change
9
Q
what cells detect a change in the internal environment of the body?
A
sensory cells/receptors
10
Q
what is a change in the internal environment called?
A
stimulus
11
Q
what are the steps in the negative feedback system?
A
stimulus –> receptor –> control centre –> effectors –> response
12
Q
what is the role of the control centre in homeostasis?
A
analyses messages and initiates actions
13
Q
how does the control centre initiate action in homeostasis?
A
sends directions through nerves/hormones to the effectors
14
Q
what do the effectors in homeostasis include?
A
muscles, organs and glands
15
Q
what is the main part of the control center in homeostasis?
A
the hypothalamus
16
Q
which system releases hormones as a response to a stimulus?
A
endocrine system
17
Q
which system releases nerve impulses as a response to a stimulus?
A
nervous system
18
Q
What is important for living organisms to control?
A
- quantities of waste (eg. nitrogenous wastes)
- oxygen and carbon dioxide concentrations
- repair of damaged cells
- removal of malfunctioning cells, pathogens and foreign substances
- input and output of water
- concentrations of nutrients such as glucose
- concentrations of dissolved salts and minerals
- body temperature and metabolic rate
19
Q
What is the hypothalamus?
A
It is a part of the brain that controls certain metabolic processes; secretes certain hormones and links the nervous system to the endocrine system via the pituitary gland.
20
Q
What is the nervous system?
A
A complex system of nerves and cells that carry messages to and from the brain and spinal cord.
21
Q
What is insulin?
A
A hormone made by the pancreas that helps maintain homeostasis of blood glucose levels.
22
Q
What is glucagon?
A
A hormone made by the pancreas that prevents blood glucose levels from dropping too low.
23
Q
What hormones is the pancreas responsible for?
A
- insulin
- glucagon
24
Q
How does insulin function?
A
- it lowers blood glucose levels by facilitating glucose transport from the blood into the cells.
- after a meal the blood glucose levels rise because the carbohydrates in the food are digested and absorbed
25
What is the difference between a positive feedback mechanism and a negative feedback mechanism?
- a positive feedback mechanism is the exact opposite of a negative feedback mechanism.
- with negative feedback the output reduces or inhibits the original effect of the stimulus. In a positive feedback system the output enhances the original stimulus.
- eg. blood clotting - once a vessel is damaged platelets start to cling to the injured site and release chemicals that attract more platelets. the platelets continue to pile up and release chemicals until a clot is formed.
26
What are protein channels?
These allow the transport of specific substances across the cell membrane.
27
What is thermoregulation?
processes designed to maintain core internal temperature and return the body to homeostasis
28
What is adipose tissue?
Connective tissue in which fat is stored
29
What is vasoconstriction?
The narrowing of the diameter of blood vessels to slow down the flow of blood, which increases the blood pressure.
30
What is vasodilation?
The widening of the diameter of blood vessels to increase the flow of blood.
31
What is the endocrine system?
A collection of glans that secrete hormones directly into the nervous system
32
What is a steriod?
A group of hormones derived from cholesterol
33
What is the importance of homeostasis?
living organisms are exposed to frequent changes in their external environment. the internal envrionment is also constantly changing
despite these changes organisms must be able to maintian a constant internal environment
34
What is the importance of homeostasis?
living organisms are exposed to frequent changes in their external environment. the internal environment is also constantly changing. Despite these changes organisms must be able to maintain a constant internal environment for optimum metabolic activity
Eg. high level of efficiency of running cells, enzymes must have the optimum temperature and pH conditions.
35
What are behavioral adaptations in endotherms that aid in the maintenance of homeostasis? (temperature regulation)
- burrowing
- nocturnal activity
- seeking shade
- cooling down in water
- stretching out to increase the surface area for heat loss
- hibernation
- migration
- curling up in a ball or huddling together to decrease
36
What are structural adaptations in endotherms that aid in the maintenance of homeostasis? (temperature regulation)
- large ears increase the surface area for evaporative heat loss
- a large surface area to volume ratio helps to maximise heat loss
- insulation such as fat layers, blubber, hair, fur and feathers
- a smaller surface area to volume ratio to minimise heat loss
37
What are physiological adaptations in endotherms that aid in the maintenance of homeostasis? (temperature regulation)
- sweating to increase evaporative heat loss
- increased blood flow to the extremities: more blood enters the skin capillaries and heat is lost
- reduced blood flow to extremities which keeps the core of the body warm
- shivering causes rapid contraction and relaxation of skeletal muscles resulting in more heat being generated
- increases in metabolic activity
38
What is an endotherm?
Endotherms use internally generated heat to maintain body temperature. Their body temperature tends to stay steady regardless of environment.
39
What is an ectotherm?
Ectotherms depend mainly on external heat sources, and their body temperature changes with the temperature of the environment.
40
What are examples of endocrine glands?
- hypothalamus
- pituitary gland
- thyroid
- adrenals
- pancreas
- ovaries
- testes
41
What does adrenaline do?
- increases heart rate
- increases blood pressure
- changes the body's metabolism
42
What does cortisol do?
- it is a steroid hormone
| - regulates processes such as metabolism and immune response
43
What is antidiuretic hormone (ADH)?
- brings about reabsorbtion of water within the body
44
What is aldesterone?
- brings about the retention of salts within the body
45
What hormones work together in maintaining water balance?
- antidiuretic hormone
| - aldosterone
46
Provide an example of how neural pathways allow homeostasis to be maintained?
Most of the signals that the human body uses to regulate body temperature are sent through the nervous system.
47
Provide an example of how hormones allow homeostasis to be maintained?
Blood glucose levels are maintained through hormone signalling.
48
What is the key difference between the nervous system and the hormone system?
- signals are sent throughout the body in two main ways
- the first is through nerves of the nervous system where they are sent as nerve impulses that travel through nerve cells called neurons
- these impulses are sent to other neurons or specific target cells at a location in the body that the neuron extends to
- the second way is through the circulatory system.
- these signals are transmitted by specific chemicals (hormones) which travel through the circulatory system
49
What is synaptic transmission?
the signals travel like a wave from dendrites to the axon and then have to cross synapses to other neurons
- synaptic transmission involves neurotransmission and signal transduction
50
What are the parts of the neuron?
https://www.sciencefacts.net/parts-of-a-neuron.html
| dendrites, nucleus, cytoplasm, cell body, myelin, axon, terminal buttons
51
Describe two mechanisms in plants that allow water balance to be maintained.
- One mechanism is metabolic processes such as decreasing photosynthesis in response to water stress through stomatal closure.
- Another structural adaptations such as deep root systems that can access water from deeper in the coil.
52
How do negative feedback loops maintain homeostasis for temperature?
- thermoreceptors detect temperature changes
- external temperature changes are detected by receptors in the skin
- internal changes are detected by receptors in the hypothalamus
- these inputs are then sent via the nervous system to the appropriate effectors such as muscles and glands
- the subsequent response brings about changes depending on whether it is cold or hot.
53
What do neural pathways consist of?
- central nervous system (brain and spinal cord)
| - peripheral nerves
54
What is a neurone or nerve cell?
- basic unit of the nervous system
| - nerve cells transmit signals by electrochemical changes in their membranes
55
How do the nervous system and hormonal system coordinate to maintain the internal environment within tolerance levels?
- the nervous system provides rapid, short-term coordination of internal organ systems
- the hormonal system provides slower, long-lasting response coordination
56
What do hormones do?
- produces by the endocrine system, they alter metabolism of target cells, tissues or organs by increasing or decreasing their activity
- they are released into the bloodstream, where they reach target cells via the circulatory system
57
Explain the order of the negative feedback mechanism.
- stimulus: a change in the environment
- receptor: detects the change in environment
- control centre: controls the response
- effector: receives the message and carries out the response
- response: mitigates the original stimulus, hence the negative feedback
58
What are the general trends and patterns on thermoregulation?
- changing behaviour eg. curling up into a ball to keep warm
- increasing or decreasing metabolic heat production eg. muscle contraction through behaviours such as shivering or rubbing hands increases muscle activity and boost heat production
- controlling the exchange of heat with the environment includes structural and physiological circulatory mechanisms such as altering blood flow patterns eg. vasoconstriction
59
What are some plant structures that assist in water balance?
- used for water uptake and minsiming water loss in times of water stress
- thin leaves with a waxy cuticle, sunken stomata, stomata on the underside of the leaf
- deep root systems allow plants to access water from deeper soil layers
- plants may grow sparsely to minimise competition and have shallow extensive root systems to enable water uptake as soon as it rains
- decreasing photosynthesis in response to water stress
- dropping leaves in response to water stress throught the production of abscisic acid
60
What are non-communicable diseases (NCDs)?
- another name for non-infectious diseases
| - NCDs have now exceeded infectious diseases as the leading cause of death and disability worldwide.
61
What are non-infectious diseases?
- they are diseases and disorders caused by something other than a pathogenic organism
62
What are some causes of non-communicable diseases?
- genetic disorders
- environmental exposure
- poor nutrition
- cancer
(typically a combination of factors)
63
What are genetic disorders?
They are inherited diseases caused by genetic mutations passed down from parent(s) to offspring
64
What are some example sof non-infectious diseases?
- sickle cell anaemia (caused by a gene mutation)
| - Down syndrome (caused by an additional chromosome 21)
65
What is cancer?
- Disease of the body's cells
66
How does cancer develop?
- cells normally grow and multiply in a controlled way but if something causes a mutation to occur in the cells' DNA (or mitochondria) this control can be lost
- cancer or tumour is the term used to describe the collections of these cells growing and potentially spreading within the body
67
What is an example of cancer?
- breast cancer - abnormal growth of the cells lining the breast lobules or ducts. Main risk factor is a strong family history of the disease.
- lung cancer - is a malignant tumour starting in the tissue of one or both lungs; tobacco smoking causes majority of lung cancers
68
What factors contribute to diseases caused by environmental exposure?
- exposure to a range of potential mutagens in the environment
eg. hydrocarbons, pesticides, certain foods, pollution, cigarette smoke
69
What are some diseases caused by environmental exposure?
- pleural mesothelioma - cancer caused mainly by exposure to asbestos
- skin cancers - (eg. malignant melanoma) caused by excessive exposure to ultraviolet radiation.
70
What are nutritional diseases caused by?
- nutritional deficiency of an important compound such as protein, vitamin or mineral and/or undernutrition. eg. night blindness caused by vitamin A deficiency
- excess in diet and other behavioural risk factors, such as unhealthy eating and lack of physical exercise eg. diabetes and obesity
- eating disorders eg bulimia, anorexia nervosa
71
What is epidemiology?
- it is the systematic and ongoing collection, analysis and interpretation of data about epidemics.
- it identifies correlations between disease and risk factors to understand the causes of diseases and the populations of most risk
72
What are some factors that can be considered when evaluating epidemiological studies?
- value and scale of the study
- length of time involved
- the specificity of the population and the site
- an assessment of the evidence and any limitations in the study
73
What are the actions of preventing a non-infectious disease?
- actions to reduce or eliminate the onset, causes, complications or the recurrence of disease
74
What is a population-based approach against disease?
- focuses on populations rather than individuals
| - focuses on prevention rather than on treatment
75
What is a life-course approach against disease?
- a life-course prevention recognises that many chronic diseases are the result of risks that accumulate throughout an individual's lifetime and that these risks can and must be reduced and prevented at all stages of life
76
How do you evaluate the effectiveness of current disease prevention methods?
- examine the extent to which the prevention method(s) contributed to a decline the in the incidence and prevalence of disease
- make judgments against a number of criteria, including the level of protection
77
What are the benefits of engaging in an epidemiological study?
Benefits include:
- being able to identify risk factors
- to determine the resources needed for health care, education and research in order to develop large targeted health interventions that are cost and resource effective
78
What is an example of an epidemiological study and its benefits?
- cervical cancer is the fourth most common worldwide cancer in women.
- In the last two decades epidemiological studies have shown that cervical cancer is a rare outcome of a commonly sexually transmitted infection caused by some types of human papillomavirus (HPV)
- epidemiological studies have clearly and consistently shown the key determinants of infection in women
- Findings from studies have resulted in the use of pap smears and, more recently, screening and vaccination strategies for the prevention of cervical cancer
79
What are some prevention methods and strategies that have provided evidence for the control of non-infectious diseases?
- 'Slip, Slop, Slap' campaign - education program for the community-wide sun protection
- 'Quit smoking' and 'I Can Quit' are national tobacco campaigns - they are anti-smoking education and mass media campaigns that target specific groups such as the young.
80
What is the global action plan of World Health Organization (WHO)?
They have a global action plan for preventing and controlling non-infectious disease
81
What is cost-effective preventive interventions?
- disease prevention method
- the evidence is largely provided by the Assessing Cost-Effectiveness (ACE) Prevention study, which was conducted over 5 years on more than 150 preventive health interventions, both population wide and individual.
- eg. tax increases on tobacco, alcohol and unhealthy foods as well as mandatory salt limits on processed foods
82
Outline the treatment and management of a nutritional disease.
- type 2 diabetes is a largely preventable disease often caused by modifiable risk factors.
- it can be managed initially through changes in lifestyle, including a healthy diet to manage blood glucose levels and body weight, and regular exercise to help insulin work more effectively.
- Future directions for further research include improving gut health
83
Outline the treatment and management of a disease caused by environmental exposure.
- the treatment of melanoma depends on the stage of the disease and the severity of the symptoms.
- Surgery is the main initial treatment.
- Additional treatments can include chemotherapy, radiotherapy, targeted therapy and immunotherapy.
- future directions for further research include the development of monoclonal antibody targeting the CDK4 antigen in order to treat advanced melanoma.
84
What are some developments in genetic technologies could be used for disease prevention?
- genetic engineering
- molecular genetics
- genetics testing
- advanced statistical methods
- high-throughput technologies
- progress in studying gene-environment interactions provide researchers with methods and strategies that potentially prevent non-infectious diseases
85
How is molecular genetics used for disease prevention?
- provides evidence that molecules that molecules and genetic pathways differ in pre-cancerous and malignant cells
86
How is genetic testing used for disease prevention?
- is used to test for the mutated genes currently known to be associated with the predisposition to certain cancers
- eg. in hereditary breast cancer the most common mutations are in genes BRCA1 and BRCA2
87
How is genetic engineering used for disease prevention?
- it helps to prevent disease - through less tested methods
- eg. the engineering of mice to stimulate a human genetic disease can then be used to develop novel prevention methods
-
88
What do ears help with?
- hearing
| - balance
89
What do disorders in the ear result in?
- disorders in the structure and function of the ear results in hearing loss or deafness
90
What is conductive hearing loss?
- it is due to problems with the canal, eardrum, middle ear or ear ossicles and is caused by middle-ear infections and damage to ear ossicles
91
What causes sensorineural healing loss?
- is due to problems of the inner ear, such as damage to the hairs or nerve cells in the cochlea caused by ageing, or cumulative exposure to excessive noise or certain drugs.
- when the cells are damaged electrical signals are not transmitted efficiently
92
What is mixed hearing loss?
- it is a combination and sensorineural hearing loss to the outer, middle and inner ear or auditory nerve.
93
What do eyes help with?
- sight
| - balance
94
What are some common disorders of the eye?
- myopia or near-sightedness (short-sighted)
- hyperopia or far-sightedness (long-sighted)
- cataracts
- macular degeneration
- glaucoma
95
What is the cause of myopia?
A refractive error caused when the distance between the lens and the retina is too great
96
What is the cause of hyperopia?
a refractive error caused when the distance between the lens and the retina is too short
97
What is the cause of cataracts?
A degenerative condition in which the lens of the eye clouds over
98
What is the cause of macular degeneration?
A progressive degeneration of the macula of the retina (the central inner lining of the eye)
99
What is the cause of glaucoma?
Caused by damage to the optic nerve due to increased pressure within the eyes
100
What is the function of the kidneys?
- kidneys are complex organs of the excretory system
- the main function of the kidneys is to filter blood of wastes and produce urine without the loss of too much water
- kidneys also assist in the homeostasis of water, glucose, and inorganic salts.
101
What is a nephron?
- a nephron is the functional unit of the kidney
- it regulates water and soluble substances in the blood by filtering the blood, reabsorbing what is needed, and excreting the rest as urine.
- Its function is vital for homeostasis of blood volume, blood pressure, and plasma osmolarity.
102
What are disorders related to the kidneys?
- chronic kidney disease caused by the risk factors such as smoking, high blood pressure, obesity and diabetes
- acute kidney injury caused by injurym trauma or severe inflammation that restricts blood supply to the tissues
- nephritic disease or inflammation of the kidney
103
What is the cause of nephrosis?
it results from a problem with the functioning of the glomeruli.
When the glomeruli are damaged, proteins from the blood leak into the urine.
104
What are some technologies used to assist with the effects of hearing loss?
- hearing aids
- bone conduction implants
- cochlear implants
105
How do hearing aids function?
- they consist of a microphone that picks up sound waves, converts them to electrical signals and sends them to the amplifier which increases the power of the signals and sends them to the speaker
106
How do bone conduction implants function?
- they are used for conductive hearing loss
- a sound processor captures sounds and turns them into vibrations
- the vibrations are sent to the implant which transmits the sound through bone vibrations to the inner ear
107
How do cochlear implants function?
- also called bionic ears
- used to help people who have severe to profound hearing loss
- a sound processor worn behind the ear picks up sounds and converts these into an electrical impulse which is sent to a receiver attached to the skull
- the receiver relays the electrical impulse to an electrode array surgically inserted into the cochlea
108
What are some technologies used to assist visual disorders?
- spectacles and contact lenses
- laser surgery
- cataract surgery
109
How are spectacles and contact lenses used to assist with the effects of visual disorders?
- they are artificial lenses designed to correct the refractive errors of myopia and hyperopia
110
How is laser surgery used to assist with the effects of visual disorders?
- it is a form of vision correction that involves reshaping the cornea to correct refractive error.
- the technology uses a cool-temperature laser and LASIK surgery is the most common form.
111
How is cataract surgery used to assist with the effects of visual disorders?
- involves the removal of the opaque lens and its replacement with a clear artificial lens (called an intraocular lens)
112
How is haemodialysis used to assist with the effects of loss of kidney function?
- done at least 3 times a week and lasts for four to five hours.
- during haemodialysis, needles are used to access blood.
- one needle takes the blood out for treatment and the other needle returns the blood.
- the blood is taken through a special filter called a dialyser, which cleans it before it is returned to the body.
113
How is peritoneal dialysis used to assist with the effects of loss of kidney function?
- it is done at home and uses a tube that is put into the stomach.
- special peritoneal dialysis fluid is used to clean the blood .
- the fluid must be changed regularly
114
How is a kidney transplant used to assist with the effects of loss of kidney function?
- the surgery involves a healthy kidney being taken from one person and surgically placed into someone with end-stage kidney disease
115
What factors are considered when determining the effectiveness of technologies used to manage and assist with the effects of disorders?
- the extent to which it manages and assists with the effects of the disorder
- the cost and affordability
- potential side affects
- risks associated with intervention (eg. surgery)
- the life of the technology
116
How effective are hearing aids?
- relatively cheap and easy to install
| - with the advantages of technology they have become much smaller and digitised.
117
How effective is cataract surgery?
- is highly effective and takes less than 30 minutes to perform.
- once the opaque lens is replaced with an artificial lens it is not possible to develop another cataract
118
Is the process of dialysis effective?
- because the process of dialysis does not match the complexity of the natural kidney it must be performed for the rest of the person's life or until they receive a kidney transplant
119
What is the Bowman’s capsule?
A cup-like sac at the beginning of the tubular component of a nephron in the mammalian kidney.
120
What is the proximal tubule?
The first and primary sort of water and ion reabsorption in the kidney, where all glucose in the blood is reabsorbed.
121
What is the glomerulus?
A small, intertwined group of capillaries within the nephrons of the kidney that filter the blood to make urine.
The glomerulus is the site in the nephron where fluid and solutes are filtered out of the blood to form a glomerular filtrate.
