Module 8: Non-Infectious Diseases

Question 1

What is homeostasis?

Answer 1

The process by which an organism maintains a stable internal environment, despite fluctuating external environmental conditions.

Question 2

Why is homeostasis important?

Answer 2

-By maintaining constant conditions (temp, pH, levels of water) in the body our enzymes are ableto carry out their functions efficiently.
-Cells survive best in an isotonic solution: needs to be maintained so that cells don’t shrink of expand
-Enzymes are very important catalysts which require specific conditions to function at their best.

Question 3

What is the internal environment?

Answer 3

The internal environment (of a cell) is the fluid surrounding a cell within a multicellular organism. It is internal to the organism, but the environment of the cell. Depending on where the type of cell, the internal environment could be blood plasma, tissue fluid or cerebrospinal fluid.

Question 4

How is the general internal equilibrium maintained?

Answer 4

Adjusting physiological processes including body temperature, CO2 concentration, blood pH, blood glucose levels and water balance.

Question 5

What is a negative feedback loop? (General detecting and counteracting of change)

Answer 5

Detecting change: receptors (sensory cells) within the body detect a change in a particular component of the internal environment (e.g. temperature, blood pH). This change is called a stimulus.
Counteracting the change: a response occurs that will reverse (or counteract) the change, which is brought about by the effector organs and will restore the body to its constant internal state.

Question 6

Temperature and thermoregulation (increase in body temp)

Answer 6

→ increase in body temp, messages are sent to the front of the hypothalamus (the heat-loss control centre) which initiates the process to cool the body
→ vasodilation – blood vessels dilating, heat radiates from skin surface
→ activation of sweat glands to secrete sweat, removing heat from the body when it evaporates

Question 7

Temperature and thermoregulation (decrease in body temp)

Answer 7

decrease in body temp, messages are sent to the back of the hypothalamus
→ vasoconstriction – blood vessels constricting, removing blood from skin surface + conserving heat
→ shivering begins + heat is produced

Question 8

Glucose (rise in glucose levels)

Answer 8

→ rise in blood glucose levels, specialized cells in the pancreas detect the increase,
→ triggers the release of the hormone, insulin which then causes blood glucose levels to decrease

Question 9

Glucose (drop in glucose levels)

Answer 9

→ blood glucose levels decrease, this is detected in a different group of cells in the pancreas
→ the hormone glucagon is released, and is then converted to glucose in the liver
→ blood glucose levels increase

Question 10

What are receptors?

Answer 10

Receptors are responsible for detecting stimuli, any changes from set point, that are outside tolerance limits. They contain sensory cells and can take numerous forms depending on stimuli.

Question 11

What are the different kinds of receptors?

Answer 11

→ Photoreceptors = detect light
→ Thermoreceptors = detect changes in temperature – heat
→ Osmoreceptors = detect changes in water levels
→ Chemoreceptors = detect concentration of certain chemicals

Question 12

What is the stimulus response model?

Answer 12

The nervous system takes messages from receptors → the CC interprets the correct response to the information → sends messages to effectors in order to respond to the stimulus

Question 13

The nervous system

Answer 13

The nervous system is responsible for coordinating all of the body’s activities. It acts as a control centre to coordinate activities that maintain homeostasis within the body. Neural pathways by which messages travel in the body are provided by the nervous system. It is composed of the central and peripheral nervous system.

Question 14

What is the central nervous system?

Answer 14

CNS consists of the brain and spinal cord where it gathers information from all over the body + coordinated responses.

Question 15

What is the peripheral nervous system?

Answer 15

PNS comprises all the nerves that lie outside of the CNS, connecting the CNS to the rest of the body. It carries messages to and from the CNS

Question 16

What is a neuron?

Answer 16

Neurons are information messengers. They use electrical impulses and chemical signals to transmit information between different areas of the brain, and between the brain and the rest of the nervous system.

Question 17

What is a cell body, dendrite and axon?

Answer 17

• Cell body = contains a nucleus and many other organelles
  → Dendrites = branch off the main cell body, receive messages in the form of impulses
  → Axons = long extension of the cytoplasm of the cell body – it transmits the electrical impulse down the neuron and is connected to the muscle to tell them what to do.

Question 18

Sensory neuron

Answer 18

→ found in PNS
→ connected to sensory organs (eyes ears nose tongue skin) and detects stimuli
→ carry impulses from sensory cells in PNS to CNS

Question 19

Interneuron

Answer 19

→ found in CNS
→ receives messages/impulses from sensory messages + sends response message to motor neurons

Question 20

Motor neuron

Answer 20

→ found in PNS
→ receives message from CNS
→ connect to muscles, glands + organs (effectors) to carry out the response

Question 21

What are hormones?

Answer 21

The main component of the endocrine system are hormones, which
are chemical messengers molecules secreted by endocrine glands.

Question 22

How do hormones assist homeostasis?

Answer 22

➔ These hormones are transported by the bloodstream to cells
possessing the receptors for the particular hormone.
➔ The hormones cause these cells to change their activity in a way that
will maintain homeostasis within the body.
➔ Hormones achieve this by influencing the activity of particular
enzymes or the concentration of these enzymes in the cells, known
as target cells.

Question 23

What is the endocrine system?

Answer 23

The endocrine system is a collection of glands that produce hormones that regulate the activity of the body such as metabolism, growth and development, tissue function, sexual function, reproduction, sleep etc. Glands can be stimulated to secrete hormones (chemical messenger molecules) by messages from the nervous system, by other hormones or by receptors

Question 24

Behavioural adaptations (temperature)

Answer 24

-Movement (shaded areas regulate heat exposure), deliberate muscle use (contractions create heat), sunbaking (surface area for heat absorption), licking (heat evap through saliva), drinking water (fluids to maintain cells in an isotonic state)

Question 25

Structural adaptations (temperature)

Answer 25

-Insulation: feathers, fur etc trap a later of air next to skin to reduce the transfer of heat to environment -SAVR: more compact bodies reduce the surface area for heat exchange- retaining heat

Question 26

Physiological adaptations (temperature) (vasoconstriction and dilation)

Answer 26

-Vasoconstriction- (narrowing), Vasodilation (widening) allows animals to regulate the SAVR of their circulatory systems to retain or expel heat when required

Question 27

Physiological adaptations (temperature) (metabolic rates)

Answer 27

-Can be increased to increase the production of heat energy internally, deceased to cool body temperature

Question 28

Physiological adaptations (temperature) (muscle contraction)

Answer 28

-Shivering or making small in the skeletal muscles to produce heart

Question 29

Physiological adaptations (temperature) (sweating)

Answer 29

-As perspiration allows sweat to evaporate from the surface of the skin which has an evaporative cooling effect

Question 30

Physiological adaptations (temperature) (panting)

Answer 30

-Allows evaporation from internal body surfaces, such as nasal passages, mouth and lungs which has a cooling effect

Question 31

What is transpiration-cohesion-tension theory? (brief)

Answer 31

Its the mechanism by which water flows through the xylem of plants

Question 32

Transpiration-cohesion-tension theory process

Answer 32

Transpiration- evaporation of water through the stomata of plants Cohesion- that water molecules are attracted to one another, so they will move in a cohesive stream Tension-Water molecules are attracted to the surfaces they touch (by regulating the levels at which transpiration occurs- retain or release water as required

Question 33

Homeostasis in plants (smaller leaves)

Answer 33

-Smaller leaves- reduces SAVR (reduces area available for transpiration- less water)

Question 34

Homeostasis in plants (closing stomates and movement)

Answer 34

-Closing stomates: inhibits the ability for water to leave the plant through the leaves -Movement- angling leaves away from the sun at different times- reduce transpiration (cool)

Question 35

Homeostasis in plants (Dropping leaves in summer)

Answer 35

-Dropping leaves conserves water to essential parts of the plant

Question 36

What causes genetic diseases?

Answer 36

-Gene or chromosomal abnormalities caused by point or chromosomal mutations -Errors during gamete formation or exposure to mutagen -Could be inherited from parents or as a result of acquired changes to pre-existing genes

Question 37

Examples of genetic diseases

Answer 37

-Down Syndrome and cystic fibrosis

Question 38

Examples of environmental disases

Answer 38

-Minamatta (ingestion of mercury) -Mesothelioma (cancer as a result of asbestos exposure)

Question 39

What causes environmental diseases?

Answer 39

-Interactions with the environment- factors such as radiation -Exposure to harmful or toxic chemicals such as toxic metals or noxious gases

Question 40

What causes nutritional diseases?

Answer 40

-Issues with diet- excessive or insufficient consumption of food -Problems with digestion -Consumption of incorrect amounts of foods

Question 41

Examples of nutritional diseases

Answer 41

-Scurvy and type 2

Question 42

What causes cancer?

Answer 42

Many different factors- infectious agents, genetic disorders, exposure to mutagens, lifestyle choices like alcoholism

Question 43

Examples of cancer

Answer 43

Breast cancer (inherited), melanoma (sun), lung cancer from smoking

Question 44

What is cancer itself?

Answer 44

-A disease in which abnormal cells grow in an uncontrolled manner. -It is the result of changes to the fundamental molecular changes of a cell due to mutation -In normal cells, growth and division are tightly regulated so that cells can function correctly

Question 45

What can cancerous cells do? (alteration of cellular regulation)

Answer 45

-Replicate indefinetly -Evade growth supressors in the body -Resist cell death -Induce increased blood flow to the tumour site -Invade other tissues and metastises

Question 46

Changes to cellular function effects (cancer)

Answer 46

Cancerous cells have the potential to metasise meaning invade or spread around the body. Tumours are the uncontrollable division of cancerous cells

Question 47

What is epidemiology?

Answer 47

The study of, incidence, distribution and possible control of diseases. Patterns and causes of diseases within populations

Question 48

What are the features of valid epidemiological studies?

Answer 48

-Large sample sizes, select populations with unequal exposure to possible causes- must include an independent variable and allow valid conclusions to be drawn, collect data on other factors (sex, lifestyle etc)

Question 49

Case study: Obesity (classification)

Answer 49

Nutritional disease

Question 50

Case study: Obesity (Cause)

Answer 50

High calorie diets and sedentary lifestyle

Question 51

Case study: Obesity (Global patterns)

Answer 51

-13 percent of all adults are obese -2.8 million die as a result of obesity -Highest in America and lowest in South East Asia

Question 52

Case study: Obesity (Contributory factors)

Answer 52

-Changes in diet (processed) -Changes to lifestyle- work and leisure etc

Question 53

T2D- Prevention

Answer 53

-Normal weight, eating a healthy and varied diet, exercising regularly

Question 54

T2D- Treatment and management

Answer 54

-Eating well- helps to manage levels of blood glucose- high fibre diets, low fat, avoiding refined sugars and carbs, low GI -Exercise, monitoring blood glucose, treatment (metformin-increase insulin sensitivity to take glucose), insulin injections, bariatric surgery

Question 55

T2D- further directions for research

Answer 55

-Inc understanding of the factors contributing to T2D -Future research- genetic risks and analysing genomes- risk of developing disease (pre-emptive, personalised medicine), organ transportation, islet cell transplants for diabetics- growing health external cells and inserting

Question 56

Asbestos causes

Answer 56

-Inhaled asbestos fibres- inflammatory reaction in lung tissue -lack of oxygen uptake in blood

Question 57

Melanoma stats

Answer 57

-In 2009-2013- 90% chance of survival -Number of new cases per year jumped from 3000 in 1982 to 12000 in 2013

Question 58

Treatment of melanoma

Answer 58

Early detection, surgery removal of cancerous cells, radiation, x ray, chemo, targeted therapies (DRUGS AFFECT MOLECULES OF TUMOR GROWTH), immunotherapy- own immune system- vaccinations and checkpoint inhibitors

Question 59

Melanoma future directions

Answer 59

-target therapies- interupting uncontrolled cell division -immunotherapy- not successful with all patients

Question 60

Benefits of engaging in an epidemiological study

Answer 60

-Comprehensive and wide reaching in their implications and applications - Cause and patterns of disease -Implementing hbp

Question 61

Effectiveness of SLIP SLOP SLAP

Answer 61

-incidence of melanoma has increased (somewhat), but basal cell carcinoma and squamous cell has decreased -effective amongst younger people -cost effective

Question 62

Eval a method used in an epidemiological study PIMA INDIAN POPULATION- Native Americans (about)

Answer 62

-Physical activitity and a decrease in T2d -NativeAmerican Community in Arizona -Carried out from 1987-2000 15-59 -Every 2 years glucose test, physical examination

Question 63

PIMA Indian Method

Answer 63

-Interviewd about their activity -leisure and occupation were recorded -average work schedule, walking hours, time spent sitting- exercise intensity -if they were incapable of recording properly they were excluded -Follow up visits -Incidence rates were calculated by age groups, gender, and physical activity

Question 64

PIMA Indian evaluation

Answer 64

-Large sample size, long period, scientifically approved methods, collecting and analysed data -non diabetics of all ages and groups were tested -objective means- doctor diagnosis- no measurement bias -BMI index etc

Question 65

Genetic engineering to prevent non-infectious diseases (general)

Answer 65

-Many non-infectious diseases are the result of mutations to genetic material -Curing diseases using genetic engineering -Changing genetic code

Question 66

Genetic enginerring (Gene therapy)

Answer 66

-Introducing a normal, functioning gene into cells, correct sequences, fixing illnesses like cystic fibrosis -vectors such as attenuated viruses

Question 67

CRISPR

Answer 67

-Point mutations may be accurately introduced into genomes, alter genomes of all edited cells- lasting somatic cell edit

Question 68

Embryo screening or editing

Answer 68

-Couples who are known carriers -Without genetic defect for implantation- whole organism changes

Question 69

Effectiveness of genetic engineering to prevent disease

Answer 69

-Mapping human genome and GWAS- bias of infectious disease -Identofying mutations that cause people to be predisposed to disease -Screening, diagnosis, early prevention, creating vaccines

Question 70

Developing strategies to prevent a non-infectious disease outbreak

Answer 70

-uses epidemiological studies to minitor trends, emerging patterns and prevalence -Locations at high risk, planning policy, strategies, preventions

Question 71

Developing strategies to prevent a non-infectious disease outbreak (how)

Answer 71

-public health campaigns, social media, disseminate information, driving conversation, legislation

Question 72

Structure of the ear

Answer 72

1. Outer ear (pinna and ear canal) 2. Middle ear (osciles and ear drum) 3. Inner ear (Cochlea, auditory nerve, and brain)

Question 73

Function of the ear

Answer 73

Ear transfers energy in different forms from the external environment to the brain.When sound enters the ear in the form of waves, the ear drum vibrates. This vibration movement causes the bones of the middle ear, the ossicles, to move in a chain-like fashion. This movement ‘knocks’ on a membrane window of the cochlea. The cochlea is filled with fluid, which moves in response to this knock. Hair cells lining the cochlea are bent in response to the fluid vibrations, which creates an electrical impulse to be sent along the auditory nerve and to the brain.

Question 74

What is conductive hearing loss?

Answer 74

-Caused by a problem with the mechanical conduction of vibrations through the outer and middle ear- ineffective sound transfer -ear infections perforation of the eardrum

Question 75

What is sensorineural hearing loss?

Answer 75

Damage to the inner ear, may arrive at cochlear but isn't passed to auditory nerve or auditory might be broken. Could be congenital or from age

Question 76

Structure of the eye

Answer 76

Sclera- forms the oaque, tough protective coat that surrounds the eye, transparent cornea Choroid layer- contains blood vessels, the posterior of the choroid is black to make the light tight and reduce the scattering or reflection of light in the eye- forward section is cillary body, lens, iris -Inner layer- retina

Question 77

Function of the eye

Answer 77

1.Light enters the eye firstly through the cornea 2. The cornea refracts light through the pupil, the width is controlled by the iris 3. Pupils dilate and contract to let in light or keep it out 4.Light passes through the lens which focuses light by shortening or lengthening the width 5. Globe of the eyeball is filled with vitrous gel that gives the eye spherical shape whilst allowing light to be transmitted 6. Light rays come to a focal point where the image is focused at the retina 7. As light hits the retina light energy is turned into electrical impulses by rods and cones, sending the message to the optical nerve and to the brain by processing

Question 78

Refractive errors

Answer 78

Occurs when the eye does not focus light properly, due to an incorrect shaping of the cornea

Question 79

Myopia (nearsightedness)

Answer 79

-Cornea is too curved or the eyeball is too long- resulting in light refracted at an angle that places the focal plane in front of the retina- far away= blurry

Question 80

Hyperopia

Answer 80

-Far sightedness occurs whenthe cornea is too flat or the eyeball is too short, light is focused beyond the retina -close up blurry

Question 81

Astigmatism

Answer 81

Vision is blurred at all distances- misshapen cornea that isn't uniform in all directions

Question 82

Structure of the kidney

Answer 82

Blood enters the kidney through the renal artery and leaves via the renal vein. The cortex is the outer part of the kidney, medualla - petal like things, pelvis- drainage area connected to the ureter Nephrons are situated across the cortex and medulla

Question 83

What is a nephron?

Answer 83

Filtering is performed by microscopic structures called nephrons, situated across the cortex and the medulla. Every kidney has about a million nephrons, each performing the job of filtration. Capillaries are wound around the nephron structures, providing an interface across which exchange of nutrients may occur. When blood first enters the kidneys, the capillaries are squeezed into a very tightly wound struc- ture called a glomerulus. This structure is so compact that all fluid in the blood (everything except red blood cells) is squeezed out, into the Bowmans capsule. In the proximal convoluted tubule, essential molecules such as water, glucose, salts and nutrients are transferred back into the capillary. The rest of the nephron structure performs a balancing function, regulating the return of salts back into the blood in response to bodily requirements. Hormones may also act on the nephron, increasing permeability to certain substances to promote their reabsorption into the blood. All wastes, excess substances and fluids are then drained into the collecting duct, which leads to the renal pelvis to eventually be drained out of the kidney and the body.

Question 84

Loss of kidney function

Answer 84

-Damage to nephrons- can t filter, reabsorp or secrete correctly -Inability to remove wastes, balancing of salt and water levels in the blood -Nausea, vomiting, HBP, fatigue, swelling, sleep problems, diabetes, kidney stones

Question 85

Cochlear implants

Answer 85

Used for sensorineural hearing loss Cochlear implants are electronic devices which replace the function of damaged inner ears (the cochlea). It enables sound, received through an external transmitter, to be transferred to the auditory nerve, allowing individuals who have damaged the hair cells of the inner ear to hear. A sound processor captures sound, and turns it into digital code. This digitally-coded sound is transmitted to the implant, which converts it to electrical impulses. These impulses are then sent along the electrode, which is placed in the inner ear. The electrode then stimulates the hearing nerve, which sends impulses to be brain to be interpreted as sound.

Question 86

Bone conduction implants

Answer 86

➔ Used for conductive hearing loss. ➔ Has a microphone that detects the sound and transforms it into vibrations, which are then passed via the implant to the bone above the ear. ➔ These vibrations are directed through the bone to the cochlea, where they are processed as normal. ➔ These implants bypass the malformed or damaged outer and middle ear and transfer the vibrations directly into the inner ear.

Question 87

Hearing Aids

Answer 87

Used for both conductive hearing loss and sensorineural hearing loss. ➔ Are used to magnify the sound vibrations to better enable their transmission to the middle ear and then the inner ear.

Question 88

Spectacles for myopia

Answer 88

➔ can be corrected by wearing spectacles with concave lenses, which are thick towards the outside and thinner towards the centre. ➔ These lenses bend the light rays outwards, causing them to diverge before they reach the eye. ➔ This extends the focal length of the light rays, allowing the focused image of a distant object to fall on the retina instead of in front of it.

Question 89

Spectacles for hyperopia

Answer 89

➔ Can be remedied by wearing spectacles with convex lenses, which are thicker towards the centre and thinner towards the edges. ➔ This type of lens bends incoming light rays inwards, causing them to begin converging before they reach the eye, shortening the focal length and allowing the focused image of a near object to fall on the retina rather than behind it.

Question 90

Laser surgery

Answer 90

➔ Used to reshape the cornea in order to correct vision problems. ➔ The surgeon will create a thin flap in the top of the cornea, which is folded back so that the underlying stroma can be accessed. ➔ An excimer laser uses short wave ultraviolet light to remove tiny amounts of tissue. ➔ This reshapes the cornea so that it focuses light more accurately. ➔ Nearsightedness = flatten cornea. ➔ Farsightedness = increase curve of cornea.

Question 91

Hameodialysis

Answer 91

➔ Waste filtered from the blood outside of the body in a dialysis machine. ➔ An A-V fistula is made in the patient's arm, from which blood is drawn, and then passed through a series of semi-permeable membranes. ➔ This allows for toxins to be drawn out of the blood into dialysis fluid, and clean blood returned to the body.

Question 92

Peritoneal

Answer 92

➔ Cleansing fluid is flown into the peritoneal cavity in the abdomen by a catheter. ➔ Wastes are filtered into the cavity from the blood. ➔ The fluid with the waste products is then drawn from the abdomen and discarded. ➔ Peritoneal dialysis can be performed by yourself at home or whilst travelling, allowing for more flexibility in lifestyle and independence.

Question 93

General effectiveness of technology

Answer 93

➔ Technologies aim to assist with the effects of a disorder and improve the quality of life of the sufferer. ➔ Without technology, individuals would have to manage to the best of their ability to cope with the effects of the disorder. ➔ Not only would these individuals be affected, but so would their families or carers. ➔ The burden on the Health & Welfare systems would be increased due to the continual support that would have to be provided.

Question 94

Advantages to cochlear implant

Answer 94

➔ The popular implant gives individuals the ability to communicate effectively with those around them ➔ These involved the use of sign language, lip reading and often a reduced ability to develop effective language skills, especially in those that are born profoundly deaf. ➔ With the implementation of the cochlear implant, those born profoundly deaf now have the ability to develop at a normal rate and showed no signs of developmental delays in language, hearing and speech. ➔ Infants will develop language and speaking skills normally. ➔ Older adults that have lost their residual hearing and have a cochlear implant are able, after a period of adjustment and training, to hear the world around them again and experience an improved quality of life. ➔ They are able to be more independent and to contribute positively to both their family and society without extra assistance.

Question 95

Advantages to spectacles

Answer 95

➔ Spectacles are affordable and easy to wear. ➔ Ready-made spectacles can now be purchased cheaply and can be effective for the wearer. ➔ Prescription spectacles are made specifically for each individual’s eye disorder and can correct for astigmatism. ➔ High refraction plastic lenses are now used to reduce the weight of thick lenses. ➔ Sunglasses are designed to protect the eyes from harmful ultraviolet radiation. ➔ You can improve your eyesight instantly.

Question 96

Disadvantages to spectacles

Answer 96

➔ Ready-made spectacles do not effectively assist with all eye disorders such as astigmatism. ➔ It is not the best solution that addresses the root cause of the vision disorder. ➔ Most people experience degrading quality of vision overtime while wearing eyeglasses. ➔ As years went by, the patient may need a stronger prescription to improve eyesight. This could happen due to the eye muscles being so used to contact with the eyeglasses that it changes shape drastically which in turn worsens vision because the eyeball focus has changed drastically. ➔ When you wear new pairs of eyeglasses you would feel a slight discomfort adjusting to it.