international baccalaureate - school of medical … · biology notes ... pathogens: prions, viruses...

INTERNATIONAL BACCALAUREATE

BIOLOGY

NOTES

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DISEASE

Disease is any condition which impairs the normal functioning of the human body. There are many causes of disease. The two main categories of disease are:

Infectious diseases

Non-Infectious diseases

INFECTIOUS DISEASE Infectious diseases are caused by disease causing agents called pathogens. There are six main types of pathogens: prions, viruses, bacteria, protozoans, fungi and parasites. These pathogens vary greatly in size and shape and also in the types of diseases they cause in their host. Find information about each of these specimens or diseases and identify which type of pathogen they are caused by (circle your selection).

DISEASE / SPECIMEN NUMBER

DISEASE CAUSING PATHOGEN:

HIV / AIDS 3035.7

Prion Virus Bacteria Protozoan Fungi Parasite

MALARIA microscope

room


HYDATID DISEASE 3000.14


TYPHOID 492.15


LUNG ASPERGILLOSIS 2130.14 Prion Virus Bacteria Protozoan Fungi Parasite

SYPHILIS display


CRYPTOCOCCOSIS 2190.9 Prion Virus Bacteria Protozoan Fungi Parasite

VARIANT CREUTZFELDT-JAKOB

DISEASE display


CHARACTERISTICS OF PATHOGENS:

Pathogens are different sizes and have a range of distinguishing characteristics.

Can you identify the pathogen type which best fits each of these characteristics? (circle your selection).

These pathogens are not made of cells and are often considered not living even though they contain nucleic acids. Vaccination may protect us from some of the diseases they cause.

Prion Virus Bacteria Protozoa Fungi Parasite

These are the smallest of all pathogens. They are made up of only protein and have no DNA or cellular structures. They cause diseases like mad cow disease.


These are the largest pathogens many of which are visible to the naked eye like tapeworms and ticks. They require a host as part of their life cycle.


These are cellular pathogens but they do not have any membranes around organelles (prokaryotic). We treat the diseases they cause with antibiotics.


These single celled pathogens are often found in water or soil and cause diseases like amoebic dysentery. Many of these pathogens are spread by vectors like the mosquito or in contaminated drinking water.


These pathogens can be microscopic or macroscopic. They have DNA and membrane bound organelles (eukaryotic). They are responsible for diseases like athlete’s foot, thrush and ringworm.


CASE STUDY: HIV / AIDS Specimen 3035.7

Specimen name

Brief history and evidence of disease

Cause and Transmission

Symptoms

Treatment, Prevention and Control

What is something interesting, surprising or useful you’ve discovered about this disease?

NON- INFECTIOUS DISEASE Non-Infectious diseases are not caused by pathogens. They are caused by various other factors and are

often the result of the interplay of genetics and lifestyle. Many of these diseases are closely related to

lifestyle factors such as smoking and obesity and much can be done to decrease your risk through positive

lifestyle habits.

TITLE:

478.24 Genetics Smoking Alcohol Environment Old age Lack of exercise

Poor diet

TITLE:


Poor diet

TITLE:


Poor diet

TITLE:


Poor diet

TITLE:


Poor diet

TITLE:


Poor diet

TITLE:


Poor diet

TITLE:


Poor diet

CASE STUDY: DIABETES 388.5

For each specimen number listed here, write in the name of the specimen under title and then identify links between these diseases and their contributing factors. In most cases, multiple factors will combine to increase an individual’s disease risk. (You may circle more than one for each disease/specimen)

Look at the “Effects of Smoking on the Body” display. List four diseases that can be linked to smoking. Identify how smoking can affect women and men. Give three reasons why quitting is an advantage.

CASE STUDY: DIABETES 388.5

Specimen name


Cause and Transmission

Symptoms

Treatment, Prevention and Control


THE TRANSPORT SYSTEM (6.2)

Look at the posters and displays on Diabetes. What causes TYPE I Diabetes? What causes TYPE II Diabetes? What are some of the effects of diabetes on the body? How can risk factors for diabetes be reduced?

Look at the display of fats, sugars and salts in common foods. Record some data about a food/ foods shown in the information in this display?

What is atherosclerosis? How does it affect blood flow around the body? Sketch and label a cross-section of a coronary artery affected by atherosclerosis.

List seven risk factors for Atherosclerosis.

CASE STUDY: CARDIOVASCULAR DISEASE

Cardiovascular disease is a general term that refers to diseases of the heart and blood vessels. Although death rates for CVD are declining, it remains a leading cause of morbidity and mortality in Australia. The process of atherosclerosis is the most common underlying cause of CVD and can ultimately lead to strokes, heart attacks, angina, heart failure and peripheral vascular disease.

1312.17 Myocardial Infarction 649.12 Pulmonary Embolism

485.12 Cerebral Infarction 1450.17 Gangrene

Specimen name


Cause

Symptoms and Treatment

What lifestyle (risk) factors may have been involved with the disease in this person?

Select ONE of the following specimens to study, using info sheets, posters and catalogues.

Find Specimen 3087.11 Coronary Artery Bypass Graft and associated display. What is a coronary bypass graft? What other techniques could be used to assist blood flow through diseased coronary arteries?

THE HEART The heart is at the centre of our cardiovascular system. It pumps deoxygenated blood to our lungs which

returns to the heart full of oxygen ready to be delivered by the main pumping chamber to all the tissues of

the body. It achieves this through an intricate system of channels, muscle tissue and valves.

Find the heart model or a labelled poster of the heart to identify the main parts of the heart shown below.

Heart Valves

Heart valves control the flow of blood through the heart. These valves can become damaged due to old age

or diseases such as rheumatic fever. This can lead to problems including breathlessness, fatigue and chest

pain.

Find and examine Specimen 3227.17 (Biventricular hypertrophy) to complete this section.

Below is a part of the clinical history of the specimen:

“...this patient experiences symptoms such as shortness of breath, feeling of being unwell and constant tiredness.

When examined it was determined that he had heart failure (his heart was not pumping enough blood to the rest of his

body). He also had a heart murmur (“leaky: heart valves) ...”

Artificial Heart Valves can be used as a replacement when a natural heart valve can’t be repaired. The

natural heart valve can be removed and replaced with a substitute mechanical or biological valve.

View examples of artificial heart valves and associated information in the display case.

Explain why he experienced the symptoms described above. What treatment has the patient had? How would this treatment alleviate symptoms?

THE LIVER The liver is the second largest organ in the human body. It has

many important functions including:

Production of bile, which helps carry away waste and break

down fats in the small intestine during digestion

Production of certain proteins for blood plasma

Conversion of excess glucose into glycogen for storage

(glycogen can later be converted back to glucose for energy)

Regulation of blood levels of amino acids, which form the

building blocks of proteins

Processing of haemoglobin for use of its iron content (the liver

stores iron)

Clearing the blood of drugs and other poisonous substances

Find a poster, diagram or model to label the body parts shown above.

CASE STUDY: CIRRHOSIS 478.24

Specimen name


Cause and Occurrence

Symptoms

Treatment, Management and Control


STOMACH ULCERS AND STOMACH CANCERS


1199.27 Chronic Gastric Ulcer 1112.27 Stomach Carcinoma 1234.27 “Giant” Gastric Ulcer

Specimen name


Cause and Symptoms

MUSCLES AND MOVEMENT The skeleton and muscles function together as the musculoskeletal system. The skeleton provides protection for vital organs, support for the body and a framework for muscles to act against. Damage can occur through injury or disease. Arthritis is an example of one disease that can damage skeletal joints and affect the range of movement.

Find the “Joint Disease” poster to label the following components of a normal synovial joint.


1417.6 Osteoarthritis 554.6 Rheumatoid arthritis 598.6 Femur osteoporosis

Specimen name


Cause

Symptoms

Treatment

Which of the following would be a good treatment or management option for this condition? (Circle your selection/s)

Go the imaging bay (Bay 21) and examine the X-ray of the person with Osteoarthritis.

Which hip is affected in this patient?

How has the disease changed the joint?

What is missing from damaged joints that can be seen in X-rays?

MEDICAL AND HEALTH TERMINOLOGY

Use common names and words to describe the types of organs, tissues or diseases found in each of these bays in the museum and in doing so understanding what each of the following words mean. In doing so, you may need to wander around the museum, visit each bay and read through some of the catalogues. BAY 7: HAEMATOLOGICAL ________________________________ BAY 8: PULMONARY ________________________________ BAY 11: CARDIAC ________________________________ BAY 12: VASCULAR ________________________________ BAY 13: CONGENITAL ________________________________ BAY 14: INFLAMMATION ________________________________ BAY 18: DEGENERATIVE ________________________________ BAY 19: NEOPLASIA ________________________________ BAY 22: ENDOCRINE ________________________________ BAY 24: HEPATIC ________________________________ BAY 27: NEUROLOGICAL ________________________________ BAY 30: RENAL ________________________________

Did you know?

Exercise did not become

fashionable until the late

1800’s when people started

to lead increasingly

sedentary lifestyles due to

less work involving manual

labour.

Did you know?

In and around 400 BC, Hippocrates

famously mentioned about exercise,

"If we could give every individual the

right amount of nourishment and

exercise, not too little and not too

much, we would have found the safest

way to health."

MUSEUM MAP

Syllabus Points covered:

6.2 Transport Systems (6.2.1)

6.3 Defence against Infectious Disease (6.3.1, 6.3.7, 6.3.8)

6.5 Nerves, Hormones and Homeostasis (6.5.12)

11.2 Muscles and Movement (11.2.1)

H2 Digestion (H2.8)

H4 Functions of the Liver (H4.5, H4.7)

H5 The Transport System (H5.4, H5.5)

international baccalaureate - school of medical … · biology notes ... pathogens: prions, viruses...

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