Physiology Of Health And Illness Biology Essay

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Atherosclerosis is the "furring" or hardening of the coronary arteries and is the main cause of heart disease, Foster (2003). Smith (2000) on the other hand describes it as a narrowing of the arteries that can affect them in any part of the body which can lead to stroke, poor circulation in the legs as well as heart attacks.

It develops gradually over many years and is due to a build up of cholesterol, calcium and abnormal cells. This in turn forms atheroma, which are fatty deposits in the wall of the artery, Bird (1996).The most frequent locations are the cardiac region, leading to 20% of deaths and the cerebral region with 15% of deaths. It also affects five times and four times as many men as women respectively. Amziev (1995)

The risk of developing atherosclerosis is mostly determined by the level of cholesterol in the bloodstream which can depend on dietry or genetic factors, Smith (2000). Smith also stated that as cholesterol levels have close dietry links atherosclerosis is more common in Western countries and so location is a risk factor. He added that Diabetes Mellitus can also cause high cholesterol levels regardless of diet along with some inherited lipid disorders.

Other recognised factors which increase the risk of atherosclerosis that can't be changed are heredity. Up to date figures show that this increases the chances but is this purely due to family genes or is it more down to a shared lifestyle of families such as lack of exercise, poor diet, smoking and so on. Gender seems to be a factor as stated before men are at higher risk than women. There is the menopause in women and this could be due to the ceasation of oestrogen secretions which are natural protectors of the artery walls. Again this could be linked to the last factor of age as the deposits take time to build up and so will present later in life. Amziev (1995).

Risk factors that can be changed include lack of regular exercise allowing fats to build up. Smoking causes hardening of the arteries so decreasing their flexibility and in turn allows more build up on the walls of the arteries, Foster (2003). He goes on to say that excessive alcohol consumption can lead to an increase in blood pressure which is the most common effect of atherosclerosis. Blood pressure rises when the arteries narrow and elasticity is lost as they can no longer adjust rapidly or fully to each heart beat.

Being over weight which results from a poor diet and/or lack of exercise if a contributory factor and it has been found to be particularly so if this weight is carried around the waist. If two or more risk factors occur in one person it is more likely the individual will develop atherosclerosis, Amziev (1995).

The changes brought about from suffering from this condition will be those of a change of life style. Changing diets and exercise habits, giving up smoking and reducing alcohol consumption will help prevent or delay the onset if there are no contributing factors that can not be changed as well.

10 marks

Section 3 Respiratory system

1) What is the function of the Respiratory System?

The respiratory system is made up of upper and lower sections. The upper respiratory system comprises of the nose and naval cavity, the pharynx, larynx and trachea. The lower is made up of the lungs, bronchi and bronchioles, respiratory bronchioles and alveoli, Waugh and Grant (2008).

The respiratory system along with the circulatory system delivers oxygen to the lungs and then on to the cells and removes carbon dioxide from the cells back to the lungs for exhalation. Every cell needs a constant supply of oxygen and to get rid of carbon dioxide. Respiration is essential to allow most cells to function and is the exchange of oxygen and carbon dioxide between air, blood and body tissues, Smith (2000).

Total marks available - 3

2) How and where does gaseous exchange occur? Maximum 150 words

Waugh and Grant (2008) explain that gaseous exchange takes place continuously at the respiratory membrane and in tissues. Gould (2006) states it involves the diffusion of oxygen and carbon dioxide and depends on different pressures occurring between for example, atmosphere and blood and flows from high pressure to low pressure areas.

Internal respiration takes place at a cellular level where oxygen enters and carbon dioxide leaves it. The gases diffuse into the blood stream. Waugh and Grant (2008) defines external respiration as between the lungs and the environment while Gould defines it as the flow of gases between the alveolar air and blood in the pulmonary circulation.

Each gas diffuses according to it's own partial pressure gradient known as Daltons Law. As air comprises of oxygen, carbon dioxide, nitrogen and water and is never completely expired, the concentrations of gases are different in the atmosphere, blood and lungs and so differences in pressure allows continuous exchange.

Total marks available - 10

The following section concerns respiratory measurements. Use the choices below to match with the statements.

A. Dead space volume

B. Expiratory reserve volume

C. Inspiratory reserve volume

D. Residual volume

E. Tidal volume

F. Vital capacity

You will not need to use all of the above choices


Waugh and Grant (2008)

Respiratory volume inhaled or exhaled during normal breathing


McMorran, J., Crowther, D., McMorran, S., Prince, C., Youngmin, S., Pleat, J. and Wacogne, I. (2009)

Air in the respiratory passages that does not contribute to gaseous exchange


Waugh and Grant (2008)

Total amount of exchangeable air


McMorran et al (2009)

Gas volume that allows gas exchange to go on continuously


McMorran et al (2009)

Amount of air that can still be exhaled forcibly after a normal exhalation

5 marks

4) Describe the pathology of asthma

Defined very simply at Asthma UK (2009), asthma is an inflammatory disease of the airways.

They state that it is very difficult to say for sure what causes it but that they know that people are more likely to develop asthma if there is a family history and combined with environmental factors influences whether a person will suffer from it.

The International Study of Asthma and Allergies in Childhood (2008), studied across 155 centres in 56 countries with half a million children and found great disparities across the world with a trend toward higher incidences in developed and westernised countries. The study suggests other influences such as genetic, social and environmental risk factors. Symptoms were found to be most prevalent in the United Kingdom, Australia, New Zealand and Ireland (up to 20%) and lowest (2-3%) in Eastern Europe, Indonesia, Greece and India.

Waugh and Grant (2008) suggest that the non-specific factors that may cause asthma are cold air, cigarette smoking, air pollution, upper respiratory tract infection, emotional stress and strenuous exercise. Asthma UK (2009) expand on this by including the influences of smoking in-utero and passive smoking. They also include modern lifestyle which includes housing, diet and a more hygienic environment as factors that may have contributed to the recent rise too.

There could be an endless list of causes because asthma can be triggered by anything that irritates the airways to cause the symptoms.

Waugh and Grant (2008) put asthma into two categories and these are atopic which is childhood onset and extrinsic, and non- atopic, i.e adult onset and intrinsic. The nature and the symptoms are the same and treated in the same way. Gould (2006) states that it can further be catagorised as acute, i.e a single episode or Chronic which is a long term condition. Recently there has been a clinical scale developed ranging from mild and intermittent to severe and persistent.

Asthma UK (2009) describes asthma as the tightening of the muscles around the walls of the airways causing them to narrow and inflames and swells the lining. Sometimes sticky mucous and phlegm builds up to cause further narrowing.

Asthma Conditions (2008) advise that symptoms present themselves in many ways including a night time cough, shortness of breath, a tight feeling in the chest, sometimes wheezing and tachycardia. In severe attacks there can be clear in drawing of the area between the ribs and above the sternum and clavicles.

Smith (2000) also lists difficulty in exhaling, a dry persistent cough, feelings of panic, sweating and a blueness to the lips, tongue, fingers and toes due to the lack of oxygen which in turn can lead to exhaustion, confusion and coma. NHS Direct (2009) explain that if left untreated an attack can lead to death.

The changes a person may need to make due to suffering from asthma tend to be to their lifestyle and taking prescribed medication. It is essential to identify and then limit or eliminate personal triggers, Asthma Conditions (2008).

Following a healthy diet and keeping well hydrated, with regular medical reviews can also be beneficial, Asthma UK (2009).

10 marks

Section 4

Renal system

1,List the components of the renal system and their function

The renal system consists of all the organs involved in the formation and release of urine according to (2008). Waugh and Grant (2008) describe it of comprising of kidneys and Ureters the bladder and the urethra.

Generally there are two kidneys and ureters, but we do not need two to survive. It may just be that evolution has seen an advantage to having a spare, National Kidney federation (2009).

The kidneys are bean shaped organs and are situated just below the ribcage. They remove excess water, salts and wastes of protein metabolism from the blood while returning nutrients and chemicals to the blood, Moore, Dally and Agur (2006). Waugh and Grant (2008), simply term this as secreting urine and add that most of the filtrate is reabsorbed with just 1% excreted as urine. Each kidney contains the Hilus through which the ureters are connected. Blood vessels and lymphatic vessels are also connected at the hilus with the blood entering through the renal artery, (2009). It is also stated here that the main function is not excretion but regulation as the main process as mentioned above deals with filtration.

The Ureters are muscular tubes that take urine from the kidneys to the bladder, Drake, Vogl and Mitchell (2010). The muscles allow for peristaltic movement, Waugh and Grant (2006). Each ureter is approximately 30cm long Pentz (2003). As urine goes on to be collected in the bladder so raising the pressure, the ureters become compressed and the openings close to prevent urine reflux, Waugh and Grant (2006).

According to the McMorran et al (2009), the bladder is the storage organ for urine collected from the kidneys by the ureter before excretion via the urethra. The normal capacity is about 300-400 ml as more than this stimulates the need to urinate. In men the capacity can be up to twice as much due to a much stronger sphincter muscle.

Drake et al (2010) define the Urethra as the canal running from the neck of the bladder to an opening in the perineum and carries urine when urinating. The urethra varies in length in males and females with those in the female being about 4cm and in men being about 20cm. The external opening is guarded by the external urethral sphincter which is under voluntary control Waugh and Grant (2006). It could be argued that the control can be lessened and therefore not as voluntary if there is damage to the pelvic floor which weakens the muscle, Smith (2000).

In men the urethra which travels through the penis also carries semen. This enters the urethra from the ejaculatory duct and urine enters from the bladder, Waugh and Grant (2006).

Total number of marks - 12

2,List the common signs and symptoms of a urinary tract infection

Hackett (2009) states that a urinary tract infection (UTI) is defined as the presence of multiplying organisms in the tract through which urine flows from the kidneys via the bladder to the outside world. It is more common in women than men, probably due to the shorter length and wider diameter of the female urethra, Gould (2006). This is because most infections are ascending, originating from organisms in the perineal area.

Cystitis is the most common UTI and if left untreated can spread upwards to cause ureteritis or even pyelonephritis of the kidneys which may even lead to kidney damage, Waugh and Grant (2006)

In cystitis the urethra and bladder wall become inflamed, red and swollen and possibly even ulcerated. NHS Choices (2009) lists the symptoms as including pain, burning or stinging sensations when urinating, a frequent or urgent need to urinate but only then passing small amounts. Other symptoms listed include dark, cloudy or strong smelling urine which may even contain traces of blood, pain directly above the pubic bone, lower back or abdominal pain and finally a feeling of being unwell, weak or feverish. Gould (2006) also includes an increase in the need for night time urination.

Ureteritis rarely occurs alone Schilling (2009), and so the symptoms will be very similar to those of cystitis. There are some anatomical abnormalities that can give rise to recurrent infections occurring and so the causes can vary widely.

Pyelonephritis may affect either one or both kidneys and involves the renal pelvis and medullary tissue, Gould (2006). Vordik (2008) states that the symptoms again include those of cystitis but may be more pronounced, especially as far as back and abdominal pain is concerned. There may also be fatigue, higher fever and possibly even mental changes causing confusion. Confusion is a typical symptom in elderly where no other symptoms may present themselves outwardly. He goes on to list changes to the skin which may become warm and moist.

Total marks available - 10

3. Label this intravenous pylogram 3



1 Renal Papilla

2 Major Calyx

3 Ureter

P Renal pelvis

B Bladder

Moore et al (2006)

Section 5

Homeostasis and the endocrine system

1.Explain what is meant by the term homeostasis, 50 words

Waugh and Grant (2008), state that homeostasis literally means "unchanging" but in practice it describes a dynamic, ever-changing situation within narrow limits.

Collins (1987), defines it as the maintenance of metabolic equilibrium within an animal by a tendency to compensate for disrupting changes.

4 marks

2. Diabetes is an example of a homeostatic imbalance which involves the endocrine system.

Describe the pathology of Type 2 Diabetes

Type 2 Diabetes, according to is a common metabolic disorder and was once known as adult-onset diabetes but has now been found to occur in young adults and children. Waugh and Grant (2008) say it is non-insulin dependent and is the type of diabetes that accounts for 90% of all cases. NHS Choices (2009), puts this as high as 95%.

NHS Choices (2009) say that type 2 diabetes is caused by the body not producing enough insulin or not using what it produces effectively. Normal blood sugar is regulated by insulin which helps take glucose from blood to the cells to be used for energy. If diabetes is present the insulin is either not produced enough or there is resistance so the body can not use the glucose.

Dlife (2008), argue that the causes are not fully understood but that there is a strong hereditary link. They say that there is a 10-15% greater risk of developing the disease if a parent or sibling already suffers. They also cite an inactive life-style and poor diet possibly acting as a trigger if there is also a strong hereditary factor. Other potential causes are chronic stress, low birth weight with the associated fetal malnourishment and gene mutations. They list Ethnicity with African/ American, Asian/American, Latino/American, a history of gestational diabetes, hypertension with blood pressure over 140/90mm hg, a poor cholesterol profile and being older as increasing the risks of developing diabetes. (2009) list the symptoms as blurred vision, cuts or sores that take a long time to heal , itching skin or yeast infections, excessive thirst, dry mouth, frequent urination and leg pain. DLife (2008) add extreme hunger, unexplained weight loss, fatigue and feeling run down, rapid breathing, headaches, mood swings and urinary tract infections.

There are many changes to make in lifestyle in order to cope with diabetes. Doctors will prescribe medication which may start with tablets but progress to insulin, in order to lower blood glucose levels, (2009). Manzella, (2009) continues to state that the patient will be asked to monitor their blood glucose levels several times a day to record how their body responds to the medications, food and exercise. Understanding this will help in future food choices, activity levels and which medications are best suited.

The A1c test will be performed every 2-3 months and will determine the general trend of blood sugar levels.

Nutrition is important as there is a high incidence of diabetes in the obese, so weight loss and a healthy balanced diet would be recommended along with regular exercise. Exercise has a direct affect on the blood sugar levels. A patient will need to know how to manage in an emergency if hypoglycaemia, which is low blood sugar level, or diabetic ketoacidosis, i.e high blood sugar level occur. Warning signs must be reacted upon as either extreme can lead to coma or even death. Manzella (2009).

The main action that a patient can take is to become educated in the disease to take the best control that they can.

10 marks

Section 6

Digestive system

Briefly describe the 2 main functions of the digestive tract

The digestive system is concerned with the intake, breakdown and absorption of food substances for the use and storage by body cells Bird (1996). It comprises the mouth, pharynx, oesophagus, small intestine, stomach, large intestine, rectum and anal canal, Waugh and Grant (2008).

Digestion can be physical or chemical. The physical part is the mastication in the mouth, that is chewing, peristalsis by the muscular action of the stomach and the intestinal walls and this reduces the size of the food whilst moving it through the tract, Bird (1996).

Bird (1996) goes on to say that the chemical action of digestion includes enzymes, which allows chemical changes to take place so enabling the simplified compounds to be absorbed through the linings of the organs especially the ileum of the small intestine. This is where most food substances are absorbed.

Total number of marks - 4

2) Identify the pathologic conditions described below.









Not all the answers will be used.


Inflammation of the abdominal serosa


Condition resulting from the reflux of acidic gastric juice into the oesophagus


Usually indicates liver problems or blockage of the biliary ducts


An erosion of the stomach or duodenal musosa


Passage of watery stools


Causes severe epigastric pain; associated with prolonged storage of bile in the gall bladder


Inability to pass faeces' often as a result of poor bowel habits

Gould (2006)

7 marks

Label the Barium enema

1 Caecum. (1996)

2 Ascending colon, (1996)

3 Transverse Colon, e-radiology (1996)

4 Fundus, e-radiology (1996)

5 Sigmoid colon, Gould (2006)

6 Liver, Waugh and Grant (2008)

7 Stomach, Waugh and Grant (2008)

Section 7

Musculoskeletal system

1. Describe the healing process for fractures

(250 words maximum)

Fractures, according to Bird (1996) are a break in the continuity of the bones including cracks as well as breaks.

Bone is constantly absorbing and replacing the cells that make it and so healing is natural, Cluett, (2004).

Johnston, (1996) describes the healing process in four stages. Inflammation caused by bleeding from the injured bone and surrounding tissue.Stage two is "soft callus". Stage three is "hard callus" and stage four is "bone remodeling".

He also states that healing times vary enormously for each person depending on age, health, the type of the fracture and the bone involved.

Brown (2009) expands on this describing the inflammation stage as a blood clot forming to clean the wound area. Repair cells fill the fracture which then become osteoblasts for new bone tissue and chondroblasts for new cartilage. Over the next 2-3 months osteoclast cells dissolve and recycle bone debris.

Browns second stage incorporates 2 and 3 of Johnstons, begins about two weeks after the fracture occurs. Here, proteins produced by the osteoblasts and chondroblasts begin to merge into a soft callus which then hardens into a hard callus with the bone weaving together over a 6- to 12-week time period.

Her final stage is the remodeling phase and is where the callus begins to mature and remodel itself. Woven bone becomes stronger lamellar bone by both osteoblast bone formation cells and osteoclast bone resorption cells.

She adds that nutrition can play a big role in the healing process whilst smoking may hinder it.

Total marks 10

2. Describe

The signs and symptoms of osteoporosis 5 marks

Raisz (2008) describes osteoporosis as a progressive metabolic bone disease that decreases the bone density with deterioration of the bone structure. Drake et al (2010) describe it as the bone mineral density being significantly reduced.

NHS Choices (2009) explain that as osteoporosis develops over several years, symptoms tend not to be obvious in the early stages. Early warning signs, when they do occur, can include joint pains and having difficulty sitting or standing straight. Due to the thinning of the bones a fracture after a minor fall, impact or even a sneeze or a cough may be a key indicator.

Gould (2006), states that compression fractures of the vertebrae happens and this displays itself in back pain due to pressure on the nerves. Kyphosis and scoliosis, which are abnormal curvatures of the spine, are indicators to the spinal changes due to osteoporosis. She also states that the healing of the fractures is slow.

Waugh and Grant (2008) cite the most common bones to suffer from fractures due to osteoporosis are the neck of femur, wrists and vertebrae.

The causes and risk factors for osteoporosis 5 marks

The Association of the British Pharmaceutical Industry, Abpi (2009) show that there are many listed causes and risk factors for osteoporosis, only some of which are within a patients control. They say that the most "at risk" group are women entering or just through the menopause and especially so if this happened early, i.e. before 45.

Raisz (2008), lists many causes including being thin, insufficient dietary intake of calcium, Phosphorous, and vitamin D which is more likely to cause bone loss, as does a, high-protein diet. Because stress, including weight bearing, is necessary for bone growth, immobilization or extended sedentary periods result in bone loss. Cigarette smoking and excessive caffeine or alcohol use also adversely affect bone mass. Whites and Asians are at higher risk. A family history of osteoporosis also increases risk. Other risk factors (eg, decreasing amounts of sex hormones) predispose to specific types of osteoporosis. Patients who have had one fragility fracture are at increased risk of having others.

Waugh and Grant (2008) include the following further risk factors of being female and increasing age. Other factors may include using corticosteroids or diseases such as Cushings syndrome, hyperparathyroidism, Type 1 diabetes mellitus, rheumatoid arthritis, chronic renal failure, chronic liver disease, anorexia nervosa and certain cancers.

Section 8

The skin

1, What is a pressure sore? (Maximum 100 words)

Pressure sores are also known as decubitus ulcers or bedsores are areas of damaged or broken skin and tissue, Waugh and Grant (2008). They add that without treatment they can become deep wounds that take a long time to heal. British Medical Journal Group (2009). Gould (2006) states that the areas affected appear red and then superficial breakdown is evident leading to ulceration and the colour may become purplish red if the damage is deep. Eventually deeper tissue is destroyed and a large open area develops. Local infection is also common.

Total marks available - 3

2, How do pressure sores occur? (Maximum 100 words)

Pressure sores occur by skin break down which happens easily when the circulation is impaired, Gould (2006). Blood supply is reduced at pressure points where the skin is compressed for long periods between bony areas and a hard surface, e.g bed or chair, Waugh and Grant (2008). Due to the lack of blood to these areas death of the tissue cells occurs, leading to ulceration, Gould (2006). Gould also lists inadequate subcutaneous tissue in the elderly, sensory impairment, mechanical irritation such as friction, excessive moisture from perspiration or urine, poor personal hygiene and inadequate nutrition or hydration.

Total marks available - 5