Because they can bite one person with a disease and transmit it to other people that it bites. Also they can carry parasites.
some are harmful but some are not harmful
obesity is harmful to us because it causes many diseases
no it is not harmful to us
well its harmful to your computure
The ozone layer protects us from the sun's harmful radiation.
Chlamydomonas is not harmful to us because it is a photosynthetic organism Also a green Algae
Because some of them are harmful to us,releasing poison in our body.Because some of them are harmful to us,releasing poison in our body.Because some of them are harmful to us,releasing poison in our body.
I want the answer in 500 words how can technology be harmful?.
Physical and chemical changes are harmful to us.
yes it is harmful
its not . Oh yes it is harmful. It makes us fat and liable to heart disease.
No they are not. In fact, humans are more harmful to them then they are to us.