Questions

Chemical weathering is caused by rain water reacting with the mineral grains in rocks to form new minerals (clays) and soluble salts. These reactions occur particularly when the water is slightly acidic.

Saddam Hussein

Auto-immune disease :: Sometimes, due to genetic and other unknown reasons, the body attack self-cells. This results in damage to the body and is called auto-immune disease.

From the options,

-> Rheumatoid arthritis is an autoimmune disorder in which antibodies are produced against the synovial membrane and cartilage.

-> Vitiligo causes white patches on skin also characterised as autoimmune disorder.

-> Psoriasis is a skin disease that causes itchy or sore patches of thick red skin and is also autoimmune.

-> Alzheimer's disease is a chronic neurodegenerative disease. Alzheimer's disease is due to deficiency of neurotransmitter acetylcholine.

Hence, Alzheimer's is not the auto-immune disease.

Carbon monoxide (CO) is very dangerous because it binds with the haemoglobin more efficiently than oxygen does. It "hogs the seats" so that oxygen can't get a ride. And those CO molecules keep riding around, never giving their seats up to the oxygen. This means there is no way to get oxygen to the brain, heart, or other cells and those cells start to die. And finally, it leads to suffocation and even death of a person.