- Grade 11 and 12 Mathematics (Moderator: geoffrey)
|
|
- Grade 11 and 12 Mathematics (Moderator: geoffrey)
Looking at the sun may not only cause headache and distort your vision temporarily, but it can also cause permanent eye damage. Any exposure to sunlight adds to the cumulative effects of ultraviolet (UV) radiation on your eyes. UV exposure has been linked to eye disorders such as macular degeneration, solar retinitis, and corneal dystrophies.
When blood is deoxygenated and flowing back to the heart through the veins, it is dark reddish-blue in color. Blood in the arteries that is oxygenated and flowing out to the body is bright red. Whereas arterial blood comes out in spurts, venous blood flows.
More than 50% of American adults have oral herpes, which is commonly known as "cold sores" or "fever blisters." The herpes virus can be active on the skin surface without showing any signs or causing any symptoms.
Aspirin is the most widely used drug in the world. It has even been recognized as such by the Guinness Book of World Records.
The familiar sounds of your heart are made by the heart's valves as they open and close.