"In the early days of germ theory, contagious diseases
were thought to be caused by fungi or bacteria. In the 1890's, Dmitri
Ivanovski filtered extracts from diseased tobacco plants and discovered
that the disease could be transmitted to new plants through the
filtrate. He concluded that the disease was caused by particles smaller
than bacteria; the tobacco mosaic virus", is partially correct. Dmitri
Ivanovski discovered that filtered extracts from diseased tobacco plants
could be transmitted to new plants through the filtrate. However, it
was Dutch microbiologist Martinus Beijerinck who, while replicating
Ivanovsky's experiments, proved that the filtrate contained a new
infectious agent. Beijerinck named this agent a virus.
b
I am not that sure but I think endocrine cell don't contain blood vessels
It put stress on the nervous system.
Answer:
nitrogen, phosphorus and potassium.
Explanation:
The three main nutrients are nitrogen (N), phosphorus (P) and potassium (K). Together they make up the trio known as NPK. Other important nutrients are calcium, magnesium and sulfur.
