The first line of defence (or outside defence system) includes physical and chemical barriers that are always ready and prepared to defend the body from infection. These include your skin, tears, mucus, cilia, stomach acid, urine flow, 'friendly' bacteria and white blood cells called neutrophils.
Answer:
Aa would be ur answer:)))
More often. please correct me if I am wrong
Answer:
The correct answer is option b. "Alpha eventually replaced by theta".
Explanation:
Electroencephalogram (EEG) techniques allows researchers to monitor the phases of sleeping according of what brain waves are seen in the equipment. A normal adult connected to EEG will respond with alpha waves during a wakeful state. However, as the person becomes drowsy and enters to the first stage of sleep, the alpha waves will be eventually replaced by theta waves. Theta waves are the dominant waves during sleeping, and also could be seen during deep meditation.
