Non-Infectious Disease and Disorders

Question 1

What is Homeostasis

Answer 1

the process by which the body maintains a constant internal environment

Question 2

The importance of homeostasis

Answer 2

bring about optimal metabolic efficiency - chemical reactions within cells must occur efficiently and be effectively coordinated -> through enzymes - sensitive to changes -> internal conditions must maintained at a level that allows the optimal functioning of enzymes

Question 3

negative feedback loop temperature (cold)

Answer 3

stimulus - decrease body temp
receptor - Hypothalamus
control centre - hypothalamus activates heating system
effector - blood vessels, muscles, cells, hair erector cells
responses - Above

Question 4

negative feedback loop temperature (hot)

Answer 4

stimulus - Increase body temp
receptor - Hypothalamus
control centre - hypothalamus activates cooling mechanism
effector - blood vessels, sweat glands, cells
responses - Above

Question 5

Negative feedback loop: Glucose levels rise

Answer 5

Stimulus: blood glucose levels rise
Receptor: Beta cells in pancreas detect high BGL
Control Centre: Pancreas
Effector: Pancreas
Response: Insulin is released by pancreas to increase glucose uptake by cells

Question 6

Negative feedback loop: Glucose levels fall

Answer 6

Stimulus: BGL falls below 90mg/ 100mL
Receptor: Alpha cells in pancreas detect low BGL.
Control Centre: Pancreas
Effector: Liver
Response: Liver cells release glucose

Question 7

Thermoregulation

Answer 7

Thermoregulation is the internal regulation of an animal’s body temperature

Question 8

Endotherms

Answer 8

Warm-blooded, e.g. humans

Question 9

Ectotherms

Answer 9

Cold-blooded, e.g. lizards bathe in sun to warm up

Question 10

Osmoregulation in Plants

Answer 10

the process of maintaining salt and water balance (osmotic balance) across membranes within the body

without it water and salts can lose or gain too much water or salts by osmosis.

Question 11

Dry Environments adaptions - plants

Answer 11

Close Stomata when necessary
Waxy Cuticle
Vacuoles

Question 12

Wet Environments plant adaptions

Answer 12

Increased Stomata

Large and Flat Leaves

Question 13

Salty Environments plant adaptions

Answer 13

Salt exclusion
Salt Excretion
Salt Accumulation

Question 14

Internal coordination systems

Answer 14

Nervous and endocrine systems are internal systems that work together that homeostasis is maintained. They coordinate and provide pathways of communication for negative feedback systems that operate to maintain homeostasis.

Question 15

Receptors

Answer 15

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. They are concentrated in particular areas, forming sense organs such as eye, ear, tongue

Question 16

The nervous system

Answer 16

Neural pathways by which messages travel in the body are provided by the nervous system. There are two main parts:
central nervous system - composed of brain and spinal cord
peripheral nervous system. - comprises all other nerves throughout the body that aren’t part of the CNS.

Question 17

Case-control studies

Answer 17

Compare people with disease to people without to look for difference

They analyse differences in these two groups to eventually identify the cause of the disease, as well as lifestyle practices

Question 18

Cohort studies

Answer 18

Involves studying two or more similar groups of people who are free of the disease

The groups are separated on one factor: 1 group is exposed to the possible cause of the disease and other group is not.

These groups are followed over a long period of time.

Question 19

How Data is Collected in an Epidemiological Study

Answer 19

Diagnostic stage: where the presence of the disease is confirmed.
Descriptive stage: where the population at risk and distribution of the disease is described.
Investigative stage: where studies are implemented to investigate whether the evidence supports a hypothesis about the disease.
Experimental stage: where experiments are performed under controlled conditions to test the hypothesis.
Analytical stage: where the results are analysed.
Decision-making stage: where the knowledge gained in the previous phases is used to develop health programs or services, or direct further research.

Question 20

Limits on the Study of Epidemiology

Answer 20

Epidemiology fails to:
Provide a holistic view of health, as it primarily focuses on physical health.
Explain sociocultural factors that contribute to negative health behaviours.
Explain why health inequalities exist between different groups.

Question 21

Errors in epidemiological studies

Answer 21

Random errors

Systematic errors/bias

Question 22

How can non-infectious diseases be prevented?

Answer 22

Educational programs and campaigns
Lung Cancer Program - QUIT:
genetic engineering

Question 23

Treatments for Hearing Loss

Answer 23

Hearing Aids = are a battery-operated electronic device that fits into the hollow outside the ear canal
—– works by amplifying sound waves within the ear canal; that is, by making them louder

Bone Conduction Implants = work by creating sound vibrations, that are conducted directly to the cochlea
—– Used for treating conductive hearing loss (damage to the outer and middle ear)

Cochlear Implants = are used by people with profound hearing loss; that is, by people with profound damage to any region of the ear

Question 24

Treatment for visual disorders

Answer 24

glasses

contacts

Laser eye sugery

Question 25

Kidney - Filtration

Answer 25

Filtration is based on the size of substances - substances in the glomerular blood that are small enough will pass through the walls of the glomerulus into the Bowman’s capsule
i.e. nitrogenous wastes, large volumes of water carrying dissolved substances such as amino acids, glucose and salts (ions).

Larger molecules i.e. proteins and blood cells remain in the glomerular blood.

Question 26

Kidney - Reabsorption

Answer 26

Returns essential components that have been filtered out of the blood back into the bloodstream.

Reabsorbed: Amino acids, glucose, some quantities of ions Na+, K+, Cl-, Ca2+, HCO3-, some vitamins.

Question 27

Kidney - Secretion

Answer 27

Removal of toxic substances from the blood capillaries and tissues surrounding the tubules and their active movement into the tubules for removal such as:
Metabolic wastes - urea, uric acid, ammonia, hydrogen ions.
Drugs - penicillin, saccharin and morphine.

Question 28

Loss of Kidney Function

Answer 28

cannot carry out their filtering, reabsorption and secretion functions properly - leading to a failure to remove wastes effectively and an inability to balance water and salt levels in the blood.

Question 29

Loss of Kidney Function - symptoms

Answer 29

Nausea
Vomiting
Loss of appetite
Fatigue and weakness
Chest pain, if fluid builds up around the lining of the heart
Shortness of breath, if fluid builds up in the lungs
High blood pressure (hypertension) that is difficult to control.

Question 30

Treatments for Kidney Disorders:

Answer 30

Dialysis = is the process of removing waste products and excess fluid from blood by an external machine called a Dialyser
Renal Dialysis - carries out some of the functions of kidneys so that blood may be effectively filtered even when the kidneys are damaged.