The two body systems that affect your body while drinking cold water on a hot day is your digestive system and you cardiovascular system. The way the water is affecting your digestive system is , when you drink the water your body is regulating and your body is digesting the water. The way the cardiovascular system is affected by the water is that your body can get over heated and you need something nice and cold to calm your body temperature down.
You didn't really provide us with a list of the following diseases, however, it's safely to say that communicable diseases have many causes and they themselves are varied, with new types being discovered on a yearly basis. One type of organism which causes a communicable disease is a virus. However, they are not only limited to viruses!
Plaque buildup thickens and stiffens artery walls, which can inhibit blood flow through your arteries to your organs and tissues. Atherosclerosis is also the most common cause of cardiovascular disease. It can be caused by correctable problems, such as an unhealthy diet, lack of exercise, being overweight and smoking.
There should be a section on the home page that has help videos on those types of projects.
Steroids strengthen your muscles
