Diseases and Health Risk Factors

Diving to depth can result in mechanical distortion and tissue compression, especially in gas-filled spaces of the body. Absorption of nitrogen into blood can cause high blood nitrogen levels which can exert amniotic effect. Lungs of the deep-diver cannot serve as a source of oxygen during the dive. 

Poor people living in slum areas do not have access to clean drinking water or clean surroundings, this can cause infections among them. Education is a very important aspect to avoid causes of diseases. Therefore, (d) is the correct answer.

• Joints are points of contact between bones, or between bones and cartilages.
• Synovial joints are characterized by the presence of a fluid-filled synovial cavity between the articulating surfaces of the two bones. These joints help in locomotion and many other movements. 
• Joint pains in old people are mostly due to reduced synovial fluid.
  
• So, the correct answer is 'Reduced synovial fluid'.

Obesity is a major risk factor for metabolic syndrome. This includes hypertension (high blood pressure) and Type II diabetes, which is characterized by insulin resistance.

High sodium intake causes the body to retain water, which increases blood volume and puts extra pressure on blood vessels, leading to hypertension (high blood pressure). Other conditions like wheat allergy, obesity, and diabetes have different primary dietary causes.

Coronary thrombosis is the formation of a blood clot inside a coronary artery. This clot blocks blood flow, leading to narrowing of the lumen, increased blood pressure, and potentially a myocardial infarction (heart attack). It does not cause an increase in the thickness of the arterial muscle layer, which is a chronic structural change associated with long-term conditions like hypertension.

Cardiovascular disease is influenced by multiple lifestyle factors. A high-fat diet contributes to arterial plaque buildup, obesity increases strain on the heart, and smoking damages blood vessels. Therefore, all of these are significant risk factors.

Consuming a diet high in saturated fats can lead to elevated levels of LDL cholesterol in the blood, which increases the risk of plaque buildup in the arteries and coronary heart disease. Tooth decay is linked to sugar, while osteoporosis is associated with a lack of calcium and vitamin D.

SCUBA diving carries several physiological risks due to the underwater environment and pressure changes. Salt water aspiration syndrome occurs when fine salt water mist is inhaled, hypoxia is a lack of adequate oxygen supply, and hypothermia can result from prolonged exposure to cold water. Therefore, all of these conditions are potential medical issues for divers.

Obesity in pets is a multifactorial condition influenced by biological factors such as age, genetics, breed predispositions, and neuter status, which alters metabolic rate. Additionally, owner-related factors, including the nature of the human-animal bond (such as using food as the primary means of affection), play a significant role in the development of obesity.

Dietary risk factors for obesity include feeding excessive treats (exceeding 10% of daily energy requirements), which unbalances the diet, and failing to measure food accurately using a gram scale. Ad-libitum (free-choice) feeding and "diet drift," where owners gradually increase portion sizes or add extra table scraps over time, also contribute significantly to excessive caloric intake.

While tobacco use is a major cause of cancer, diet is often cited as a significant factor in the development of many types of cancer, making it a primary focus for prevention.

Uncontrollable risk factors for heart disease include genetics, age, gender, and race. Stress is considered a controllable or modifiable risk factor because it can be managed through lifestyle changes.

Family history and genetics are uncontrollable risk factors for heart disease because they are inherited. Diabetes, high blood pressure, and high cholesterol are often considered manageable or controllable through lifestyle and medication.