Topic 3 - Coordination, Control, & Disease

Question 1

Focus 1
Identify the main components of the central nervous system.

Answer 1

The central nervous system is composed of the brain and the spinal cord
It is the control centre for all of the body’s responses
It receives information, interprets it, and initiates a response

Question 2

Focus 1
Identify the main components of the peripheral nervous system.

Answer 2

The peripheral nervous system is composed of sensory and motor neurons
It is made up of all the nerves outside of the CNS – it is a branching system of nerves
It is responsible for detecting stimuli and initiating the response that comes back from the CNS

Question 3

Focus 1
How do neurons pass signals from one cell to the next?

Answer 3

Neurons send messages electrochemically – chemicals cause an electrical signal.
Chemicals in the body are “electrically-charged” – when they have an electrical charge, they are called ions.

Question 4

Focus 1
What does it mean when a neuron is “at rest”?

Answer 4

When a neuron is “at rest” (not sending a signal) the inside of the neuron is negative relative to the outside of the neuron.
Although the concentrations of the different ions attempt to balance out on both sides of the membrane, they cannot because the cell membrane only allows some ions to pass through channels (ion channels).
The resting membrane potential of a neuron is approximately -70mV (millivolts) – this means that the inside of the neuron is 70 mV less than the outside.
The resting potential tells us about what happens when a neuron is at rest.

Question 5

Focus 1
What is an action potential?

Answer 5

An action potential (“spike” or “impulse”) occurs when a neuron sends information down an axon, away from the cell body.
The action potential is an explosion of electrical activity that is created by a depolarising current – this means that a stimulus causes the resting potential to move towards 0 mV.
When the depolarisation reaches approximately -55 mV a neuron will fire an action potential
-55 mV is the threshold – this means that if a neuron does not reach this critical threshold level, then no action potential will fire.
When the threshold level is reached, an action potential of a fixed size will always fire – for any given neuron, the size of the action potential is always the same.
Therefore, the neuron either does not reach the threshold or a full action potential is fired – this is the “all or none” principle.

Question 6

Focus 1
Explain how synapses work.

Answer 6

Most communication between neurons occurs at a specialised structure called a synapse
A synapse is an area where two neurons come close enough to each other that they are able to pass electrochemical signals from one neuron to another
The neuron where the signal is initiated is called the presynaptic neuron, while the neuron that receives the signal is called the postsynaptic neuron
In a presynaptic neuron, there are chemical signals called neurotransmitters which are packaged into small sacs called vesicles – each vesicle can contain thousands of neurotransmitter molecules
When the presynaptic neuron is excited by an action potential, the vesicles fuse with the synaptic membrane and release neurotransmitters into the synaptic cleft
Once they are in the synaptic cleft, neurotransmitters interact with receptors on the postsynaptic membrane. They bind to these receptors and can cause an action to occur in the postsynaptic neuron
This action may involve increasing or decreasing the likelihood that the postsynaptic cell will become activated and fire an action potential
Eventually, the neurotransmitters are cleared from the synaptic cleft – some will drift away in a process called diffusion; others will be taken back to the presynaptic neuron in a process called reuptake (once back inside the presynaptic neuron, the neurotransmitter can be recycled and reused); in some cases, enzymes break down the neurotransmitter within the synaptic cleft.

Question 7

Focus 1
What is the stimulus response model?

Answer 7

Stimulus → receptor → control centre → effector → response

Stimulus = a thing or event that evokes a specific reaction in an organ or tissue
Receptor = organ or cell able to respond to a stimulus and transmit a signal to a sensory nerve
Effector = organ or tissue that produces a response
Response = an action produced by an effector

Question 8

Focus 1
Use an example to demonstrate the stimulus response model.

Answer 8

Change in light
→ retina (eye)
→ brain and spinal cord
→ muscles around the eye and iris
→ squinting and pupil shrinks
Slamming a door & producing a loud sound → ear drum (ear)
→ brain and spinal cord
→ muscles of the body
→ flinching and muscle tension

Question 9

Focus 1
What is a reflex arc?

Answer 9

A reflex (or reflex action) is an involuntary and nearly instantaneous movement in response to a stimulus.
Reflexes are used to protect the body and are faster than a reaction.
A reflex does not go to the brain before a response occurs, rather the spinal cord coordinates the response by the effector.
The aim of reflexes is to protect the body from harm. Babies are born with many additional reflexes that they grow out of and many animals have reflexes too.

Question 10

Focus 1
How does a reflex arc work?

Answer 10

Reflex arcs start when a sensory receptor receives information from a stimulus.
The information is transported by sensory neurons to the spinal cord, which coordinates a response.
The response is transported by motor neurons to an effector, which produces the response.

Question 11

Focus 1
What is a common example of a reflex arc?

Answer 11

Touching a hot pan
→ thermoreceptors in the skin
→ spinal cord
→ muscles of the hand and arm
→ quick removal of the hand

Question 12

Focus 1
What is the cerebrum?

Answer 12

Responsible for cognitive areas of brain.
Split into 2 hemispheres (left and right)
Each hemisphere receives impulses and exerts control over the opposite side of the body.

Question 13

Focus 1
What is the cerebral cortex? (grey matter)

Answer 13

Outer surface area of the cerebral hemispheres
Highly wrinkled – increases surface area of the brain and the amount of neurons within it
The human brain has approximately 20 billion neurons

Question 14

Focus 1
What is the frontal lobe?

Answer 14

Controls important cognitive skills (control panel)
Emotional expression, problem solving, memory, language, judgement, sexual behaviours, etc
Located at the front of the brain

Question 15

Focus 1
What is the parietal lobe?

Answer 15

Responsible for sensory information
Taste, temperature, touch
Located in the middle of the brain

Question 16

Focus 1
What is the occipital lobe?

Answer 16

Responsible for visual information
Interpreting and processing visual stimuli and information
Located in the back of the brain

Question 17

Focus 1
What is the temporal lobe?

Answer 17

Responsible for sounds and speech (auditory perception).
Important in language production and understanding.
Receives sensory information from the ears and converts it into meaningful units.
Located directly above brain stem and cerebellum.

Question 18

Focus 1
What is the cerebellum?

Answer 18

Latin for “little brain”
Deeply folded and highly organised structure containing more neutrons than the rest of the brain put together
Receives sensory information, regulates motor movements, and coordinates voluntary movements
Responsible for smooth and balanced muscular activity.

Question 19

Focus 1
What is the brain stem?

Answer 19

Controls flow of messages between the brain and the rest of the body
Controls basic body functions such as breathing, swallowing, heart rate, blood pressure, consciousness, awakeness/sleepiness
Consists of the midbrain, pons, and medulla oblongata.

Question 20

Focus 2
What is the endocrine system?

Answer 20

Endocrine system = collection of glands that produce hormones that regulate metabolism, body defences (immune system) growth & development, tissue function, sexual function, reproduction, mood, etc
It is a chemical messenger system of hormones released by internal glands of an organism directly into the circulatory system to regulate distant target organs.

Question 21

Focus 2
Identify the main components of the endocrine system: human growth hormone (hGH)

Answer 21

Produced by Pituitary gland
Promotes growth in children
Helps maintain normal body structure in adults
Plays a role in metabolism

Question 22

Focus 2
Identify the main components of the endocrine system: insulin

Answer 22

Produced by Pancreas
Allows glucose to enter cells to be used as energy
Maintains the amount of glucose found in the bloodstream within normal levels

Question 23

Focus 2
Identify the main components of the endocrine system: Antidieretic hormone (ADH)

Answer 23

Produced by Pituitary gland
Affects production of urine
Helps blood vessels constrict
Helps kidneys control the amount of water and salt in the body

Question 24

Focus 2
Identify the main components of the endocrine system: Estrogen

Answer 24

Produced by Ovaries
Regulates menstrual cycle
Contributes to reproductive and breast health
Contributes to cognitive health, bone health, and function of cardiovascular system

Question 25

Focus 2 Define homeostasis.

Answer 25

The process by which organisms maintain a relatively constant or stable internal environment for body cells Includes body temperature, pH, glucose, gas levels, water & salt concentrations Homeostasis consists of 2 stages Detecting changes from the stable state Counteracting changes from the stable state Stimulus → receptor → control centre → effector → response Feedback loops are the mechanisms that help maintain homeostasis In feedback systems, the response alters the stimulus

Question 26

Focus 2 What are negative feedback loops?

Answer 26

Negative feedback causes changes that bring the system back to equilibrium Most feedback loops in the human body are negative The body is trying to counteract the change in its internal environment & bring it back to equilibrium

Question 27

Focus 2 Use thermoregulation in humans to explain how negative feedback loops assist in maintaining homeostasis.

Answer 27

Normal internal temperature 36oC - 37oC Above normal temperature → thermoreceptors of skin (sensory neuron) → control centre (motor neuron) → effectors: → sweat glands produce sweat → blood vessels expand; blood rushes to extremities; red/blush → muscles attached to hair make hair lie flat; lose heat Below normal temperature → thermoreceptors of skin (sensory neuron) → control centre (motor neuron) → effectors: → muscles repeatedly expand & contract (shivering); increase body temperature → blood vessels constrict; burning glucose; converted into energy → muscles attached to hair make hair stand up; trap air; insulates body heat

Question 28

Focus 2 Use blood glucose levels in humans to explain how negative feedback loops assist in maintaining homeostasis.

Answer 28

Normal blood glucose level 4.0 - 8.0 mmol/L e.g. “eat cake” → BGL increases → pancreas releases insulin → liver converts and stores glucose as glycogen → BGL decreases e.g. “exercise” → BGL decreases → pancreases releases glucagon → liver breaks down glycogen into glucose → BGL increases

Question 29

Focus 2 What are positive feedback loops?

Answer 29

Positive feedback enhances and amplifies changes. Moves a system away from its equilibrium state and makes it more unstable. Makes the stimulus bigger, represented as a cycle.

Question 30

Focus 2 Use childbirth to explain how positive feedback loops can amplify responses in mammals.

Answer 30

→ head of baby pushes against cervix → nerve impulses from cervix are transmitted to brain → brain stimulates pituitary gland to secrete oxytocin → oxytocin is carried in bloodstream towards uterus → oxytocin stimulates uterine contractions & pushes baby towards cervix

Question 31

Focus 2 Use examples breastfeeding to explain how positive feedback loops can amplify responses in mammals.

Question 32

Focus 2 How do the nervous system and endocrine system interact in order to respond to change in mammals?

Answer 32

In a mammal, many body systems cooperate to ensure that the body cells are always functioning in an ideal cellular environment. Both the nervous system and the endocrine system can interact with other systems to bring about homeostasis (the process by which organisms maintain a relatively constant or stable internal environment for body cells)

Question 33

Focus 2 Compare the nervous system and the endocrine system.

Answer 33

Made up of: Nervous system = neurons. Endocrine system = glands. Form of transmission: Nervous system = electrical impulses. Endocrine system = chemicals (hormones) Speed of transmission: Nervous system = fast Endocrine system = slow Duration of effect: Nervous system = short. Endocrine system = long. Response: Nervous system = localised. Endocrine system = widespread (although there may be a specific target organ)

Question 34

Focus 3 What are pathogens?

Answer 34

An infectious disease = a disease caused by an organism or invective agent that is often referred to as a pathogen. Pathogens can be microscopic or macroscopic.

Question 35

Focus 3 What are antigens?

Answer 35

Any molecule the body recognises as foreign and therefore triggers an immune response On the surface of the cells in the body, there are marker molecules that identify the cell as belonging to the body When pathogens enter the body, they have chemical markers called antigens on their surface The immune system recognises these as not belonging to the body, this triggering an immune response.

Question 36

Focus 3 What are antibodies?

Answer 36

An antibody is a large, Y-shaped protein which is used by the immune system (as part of the humoral immune response) to identify and neutralise antigens such as bacteria and viruses.

Question 37

Focus 3 Distinguish between different types of pathogens: bacteria

Answer 37

Unicellular organisms. No internal membrane. Reproduce asexually & rapidly. Can cause disease by producing toxins or interfering with cell function. A few micrometres. Streptococcus - causes pneumonia (dry cough, chest pain) Mycobacterium - causes tuberculosis (blood stained sputum, cough, fevers) Living

Question 38

Focus 3 Distinguish between different types of pathogens: viruses

Answer 38

Consist of a nucleic acid molecule in a protein coat. Only able to multiple within living cells of a host. Vary widely in shape and complexity. From 20 nanometres to 250-400 nanometres. Influenza - causes flu Ebola Virus - causes ebola Herpesviruses - causes chickenpox, herpes Non-living

Question 39

Focus 3 Distinguish between different types of pathogens: prions

Answer 39

Non-living proteins altered from normal shape but chemically the same. Easily transferred between animals. Smaller than bacteria and viruses. CJD Fatal insomnia (confusion, behaviour changes, memory loss, insomnia) Non-living

Question 40

Focus 3 Distinguish between different types of pathogens: protozoa

Answer 40

Microscopic single-celled organisms with internal membranes. Reproduce both asexually and sexually. Bigger than bacteria and viruses. Approximately <50 micrometres. Malaria Toxoplasmosis Giardiasis (diarrhoea, nausea, abdominal distension, anorexia) Living

Question 41

Focus 3 Distinguish between different types of pathogens: fungi

Answer 41

Heterotrophic organisms. Unicellular (e.g. yeast) or multicellular (e.g. mould) Can reproduce both sexually and asexually. 2-10 or 5-50 micrometres. Ringworm (dermatophytosis) Candidiasis Cryptococcosis (discoloured/ cracked nails, irritation, itchiness, blisters) Living

Question 42

Focus 3 Distinguish between different types of pathogens: macro-organisms

Answer 42

Organisms visible to the naked eye. Either external parasites (ectoparasites) or internal parasites (endoparasites). Approximately 5mm. Tuberculosis Chlamydia E. coli Meningitis (fever, cough, fatigue, congestion, muscle aches, headaches) Living

Question 43

Focus 3 Describe the innate immune system: first line of defence.

Answer 43

Non-specific defence which involves the body using both physical and chemical barriers to prevent the entry of pathogens The response has no memory of encountered foreign agents. The response is always of a similar magnitude.

Question 44

Focus 3 Outline some key parts of the first line of defence (innate immune system): skin

Answer 44

Skin surface = physical barrier. Fatty acids "normal flora" = non-pathogenic bacteria

Question 45

Focus 3 Outline some key parts of the first line of defence (innate immune system): mucous membranes

Answer 45

Filters out harmful materials / pathogens. Physical barrier which prevents pathogens from entering the body. e.g. mucous lining nose and throat.

Question 46

Focus 3 Outline some key parts of the first line of defence (innate immune system): chemical secretions

Answer 46

Destroys or removes pathogens. e.g. tears, saliva, sweat

Question 47

Focus 3 Describe the innate immune system: second line of defence.

Answer 47

When/if pathogens are successful in penetrating the barriers that are in place (first line of defence) non-specific responses are quickly activated to destroy the invaders before they can harm the body.

Question 48

Focus 3 Outline some key parts of the second line of defence (innate immune system): inflammatory response

Answer 48

Non-specific defence mechanism which occurs at the site of infection When cells are infected or injured, they release chemical alarm signals including histamines Histamines cause blood vessels to dilate, increasing blood flow to the site of the injury or infection and causing the area to become red, hot, and swollen

Question 49

Focus 3 Outline some key parts of the second line of defence (innate immune system): phagocytes - neutrophils

Answer 49

Short acting phagocytes Self destruct after engulfing pathogen Smaller white blood cell

Question 50

Focus 3 Outline some key parts of the second line of defence (innate immune system): phagocytes - macrophages

Answer 50

Long lasting phagocytes Can engulf and destroy many pathogens Larger white blood cell

Question 51

Focus 3 Outline some key parts of the second line of defence (innate immune system): lymph system

Answer 51

Form a one way drainage system from all parts of the body back to a point near the heart where the cleansed lymph fluid is drained back into the blood At different points along the lymph vessels there are lymph nodes If there is an infection in the tissues, the foreign particles (as well as the dead cells and other debris) move with the tissue fluid into the lymph vessels When they get to a lymph node, the waste particles are filtered off and any foreign particles are destroyed by macrophages Swollen lymph nodes are a good indicator of infection

Question 52

Focus 3 Outline some key parts of the second line of defence (innate immune system): cell death

Answer 52

Sometimes cells die to seal off an infected area of tissue that is not being successfully defended by the body - prevents infection from spreading to other cells Wall of dead cells forms a capsule or cyst The cells inside then die, causing the destruction of infecting pathogens - debris inside is destroyed by macrophages

Question 53

Focus 3 Describe the acquired immune system: third line of defence.

Answer 53

When/if pathogens are successful in surviving the non-specific defences of the innate immune systems (first and second lines of defence) the body instigates the third line of defence It is part of the adaptive/acquired immune system and is a specific response Involves the production of 2 types of lymphocytes (white blood cells), B-cells and T-cells, which are specific to the invading particle.

Question 54

Focus 3 Outline the roles of B-Cells in the third line of defence.

Answer 54

Once it's fully mature, a b-lymphocyte displays at least 10,000 special protein receptors on its surface. These are its membrane-bound antibodies. All b-lymphocytes have them, but every individual lymphocyte has its own unique antibodies, each of which is ready to identify and bind to a particular kind of antigen. When the right B cell finally bumps into an antigen it has antibodies for and recognizes it, it binds to it. Once activated, the B cell starts cloning itself, quickly producing an army of similar cells, all with the instructions for the exact same antibodies that are designed to fight that one particular antigen. Most of these clones become active fighters, or effector cells, but a few become long-lived memory cells that preserve the genetic code for that specific successful antibody. This ensures that if and when the antigen returns, there will be a prepared, secondary immune response that's both stronger and faster than the first. The effector, or plasma cells are packed with extra amounts of rough endoplasmic reticulum, which acts as an antibody factory. These cells can mass-produce the same antibodies over and over for that particular invader, releasing them into bodily fluids at a rate of around 2,000 antibodies per second for four or five days until they die. The antibodies they make work the same way that the membrane-bound ones do, they're just free-floating, binding to all the antigens they can find and marking them for death.

Question 55

Focus 3 Outline the roles of T-Cells in the third line of defence.

Answer 55

Each T cell is unique in that it’s designed to fight only one type of intruder. Once your immune system identifies the threat, it locates the specific T cell designed to defeat it and recruits that T cell for battle. The T cell copies itself, making more T cells to defeat the intruder. These T cells that join the fight are called effector cells. When your immune system is working properly, these effector T cells destroy the threat, helping rid you of infection and disease. Your T cells continue to protect you even after the intruder’s gone. Some of your T cells become memory cells instead of effector cells. Unlike effector T cells, memory T cells aren’t fighters. Instead, they remember the intruder so that if it returns, your immune system recognizes it and quickly mounts a defence.

Question 56

Focus 3 Identify different types of T-Cells in the third line of defence.

Answer 56

Cytotoxic T cells are also called CD8+ cells because they have a CD8 receptor on their membranes. These cells get their name from “cyto,” which means cell, and “toxic,” which means poisonous or harmful. Cytotoxic T cells kill cells infected with viruses and bacteria, and they also destroy tumour cells. Helper T cells are also called CD4+ cells because they have a CD4 receptor on their membranes. Unlike cytotoxic T cells, helper T cells don’t kill cells directly. Instead, they send signals that tell other cells in your immune system how to coordinate an attack against invaders. Helper T cells signal cytotoxic T cells, B cells and another type of white blood cell called a macrophage. Suppressor T Cells reduce the activity of other T cells when necessary. They can prevent T cells from attacking your body’s healthy cells.

Question 57

Focus 3 Describe humoral immunity, as part of the third line of defence.

Answer 57

Humoral immunity works by dispatching important proteins called antibodies. They're made by special white blood cells and they patrol the body's humours, or fluids, like blood and lymph, where they combat viruses and bacteria moving around the interstitial space between cells.

Question 58

Focus 3 Describe neutralisation, as part of humoral immunity.

Answer 58

Neutralisation is where antibodies physically block the binding sites on viruses or bacterial toxins so they can't hook up to your tissues. Because antibodies have more than one binding site, they can bind to multiple antigens at the same time in a process called agglutination. The resulting clumps can't get around easily, which makes it easier for macrophages to come and engulf them. Meanwhile, antibodies are also sending chemical signals/alarms, calling in phagocytes from the innate immune system, and special lymphocytes from the adaptive system, to destroy these antigen-antibody clumps.

Question 59

Focus 3 Use an understanding of the acquired immune system to explain how vaccination works.

Answer 59

Vaccinations = a weaker / dead form of a virus which is injected into the body The body’s acquired immune systems develops a specific response to the virus During this process, memory cells are produced, which recognise and destroy the actual virus if it enters the body

Question 60

Focus 3 Describe how antibiotics work.

Answer 60

It is used to prevent bacteria cells from dividing (reproducing) Or cells continue to divide (reproduce) but they are prevented from functioning properly.

Question 61

Focus 4 Distinguish between infectious and non-infectious disease.

Answer 61

Non-infectious diseases are not caused by a pathogen and cannot be passed on from person to person Infectious disease are caused by pathogens and can be passed on through person-to-person contact

Question 62

Focus 4 Outline some classification of non-infectious disease: nutritional deficiency.

Answer 62

Occurs due to poor diet or excesses in diet. Occurs when the body is not getting an adequate amount of nutrients from dietary intake. Occurs due to an inability to absorb nutrients from the dietary intake due to some other form of health disorder.

Question 63

Focus 4 Provide an example of non-infectious disease: nutritional deficiency - scurvy

Answer 63

Scurvy is caused by a Vitamin C deficiency, caused by a lack of vitamin C in your diet. Not eating enough fruits and vegetables is the main cause of the disease. This condition is a problem in countries where populations are malnourished. Left untreated, scurvy can lead to amnia, bleeding gums, loosened teeth, bleeding under the skin, easily bruised skin, rough/scaly skin, swollen legs, opening of previously healed wounds and new wounds that don’t heal, dry, brittle hair. Treatment includes increasing the amount of vitamin C in your diet or by taking dietary supplements. Easily preventable by maintaining a nutritious diet that includes your daily recommended amount of vitamin C, and by adding fruits and vegetables by your diet.

Question 64

Focus 4 Outline some classification of non-infectious disease: genetics.

Answer 64

Caused by abnormalities in genes for example genetic mutations or changes in the number and structure of chromosomes They are usually passed down from one or both parents to their children (hereditary) People who don't have genetic conditions but could pass them to their children are called carriers.

Question 65

Focus 4 Provide an example of non-infectious disease: genetics - cystic fibrosis

Answer 65

Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) cause the CFTR protein to become dysfunctional. This means that the protein is unable to help move chloride to the cell surface. Without the chloride to attract water to the cell surface, the mucus in various organs becomes thick and sticky. In the lungs, the mucus clogs airways and traps germs, like bacteria, leading to infections, inflammation, respiratory failure, etc. For this reason, avoiding germs is a top concern for people with CF. The types of CF systems and how severe they are can differ widely from person to person, and therefore treatment plans are tailored to each person’s individual needs. Each day, a person with CF completes a combination of the following therapies: airway clearance, inhaled medicines, pancreatic enzyme supplements, fitness plans, CFTR modulators, etc. Currently, preventing CF is not possible. In the future, gene therapy may be used to prevent the disease from developing. The average lifespan for those living with CF is 44 years, and death is most often caused by lung complications.

Question 66

Focus 4 Outline some classification of non-infectious disease: environmental causes.

Answer 66

Caused due to a variety of environmental factors such as air, radiation, different toxic materials/chemicals, and lifestyle choices such as smoking.

Question 67

Focus 4 Provide an example of non-infectious disease: environmental causes - asbestosis

Answer 67

It is a chronic lung disease caused by inhaling asbestos fibres. Some of these fibres can become clogged within the alveoli, causing lung tissue scarring and shortness of breath over time. People who work in mining, milling, manufacturing, construction, or who work in the removal or installation of asbestos products are at the highest risk of asbestosis. Prolonged exposure to asbestos fibres can cause lung tissue scarring and shortness of breath. Symptoms can range from mild to severe, and usually don’t appear until many (10-40) years after initial exposure to the fibres. Symptoms include shortness of breath, a persistent, dry cough, chest tightness or pain, dry crackling sounds in the lungs when inhaling, fingertips and toes that appear wider and rounder than usual (clubbing of fingers and toes). Asbestosis dramatically increases a risk of developing lung cancer, especially if the person smokes or has a history of smoking. Treatment focuses on relieving symptoms. Medications and oxygen therapy can provide breathing support. Pulmonary rehabilitation and regular vaccinations can also help to maintain lung health. Smoking appears to increase the retention of asbestos fibres in the lungs, and often results in a faster progression of the disease - avoiding smoking would prevent this. Reducing exposure to asbestos fibres is the best form of prevention. In some countries, government laws require employers working in industries that work with asbestos products to take special safety measures.

Question 68

Focus 4 Consider some strategies to prevent non-infectious disease.

Answer 68

Reduce the major modifiable risk factors, such as tobacco use, harmful use of alcohol, unhealthy diets, and physical inactivity. Develop and implement effective legal frameworks. Orient health systems through people-centred health care and universal health coverage. Promote high-quality research and development. However, certain non-infectious diseases such as genetic diseases are currently non-preventable.