"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.
Answer:
Chromosomes are thread-like structures in organisms, found primarily in the nucleus of the cell. These chromosomes contain genetic information and are involved in cell replication and reproduction. Along with DNA, chromosomes contain histones, which are proteins that keep the chromosome bound together.
If a star of 50 solar masses were to supernova. It would most likely become a black hole.
A star is a hot body of glowing gas which starts its life in Nebulae. The stars vary in size, mass and temperature. The mass of a star ranges from 1/20 times to 50 solar mass.
The stage one of the stars is born in nebula, which is a region of very high density and then it gets condensed to a huge globule of gas and dust that contracts under its own gravity.
The next stage is a region of the condensing matter which starts heating up and glowing is known as Protostar. At stage three, hydrogen fuses and forms helium as the nuclear reactions start. Stage four is a Main Sequence star when it starts to release its energy, contraction stops and it begins to shine.
Some of the stars have mass more than 3 times of the Sun and up to 50 times the mass of the sun.
When the surviving core is between 1.5-3 solar mass, with higher contraction making it tiny and dense a Neutron star is formed. If the core is greater than 3 solar masses then the core further contracts to become a Black Hole.
The correct answer is option Observations can be made from outside the "system".
The study of the plate tectonics allows the observation of the movement of the plate tectonics. These observation can be study to determine the pattern of the movement from outside the plate tectonics system and the event occurring due to plate tectonics can be predicted.
D .............. im pretty sure its this one :)
