Answer:
The correct answer is - warning system.
Explanation:
Warning systems are a type of system that could be technical or biological in nature that can help in assessing or inform about the possible danger or change in a particular setting such as ecosystem, weather, water quality, and many others. It helps in avoiding such threats before occurring or become serious threats.
Certain biological species that live or require a particular set of conditions for their survival and reproduction can act as a biological warning system for water pollution, air pollution.
Answer:
D. Red, Orange, Yellow, Green, Blue, Indago, Violet.
Explanation:
Violet has the highest freqency and red has the lowest.
Hope this helped!
Answer:
a. deterioration of neurons that produce the neurotransmitter acetylcholine.
Explanation:
Alzheimer's disease -
It is a disease associated with memory , it is a type of dementia .
The initial stages of the disease is the remember new things , the day to day task becomes very difficult with time .
During this disease the neurons get deteriorated day by day , which are responsible to produce the acetylcholine .
Hence , the correct statement about Alzheimer's disease is ( a ) .
You see first the light wave because light travels faster than sound. Hope this helps