i think it is D, she has already constructed the hypothesis and needs is performing the experiment. there is not much of an observation stage because she is looking at a distant end result in a set time frame.
In cell biology, the cleavage furrow is the indentation of the cell's surface that begins the progression of cleavage, by which animal and some algal cells undergo cytokinesis, the final splitting of the membrane, in the process of cell division.
Why did he??????
................................
It should be an igneous rock because it formed by the volcanoes lava cooling down
Answer:
A) & B)
Explanation:
A) There are certain viruses that are present in both healthy and disease people.
Example: Polio virus is found in many human but it causes disesease in only 1% of human.
B) Viruses require host machinery for replication so they may not replicate in pure culture.
The postulate C is also violated, the virus may not produce disease in non-human experimental host because of inappropriate animal or vaccinated animal etc. Others exception includes, the same disease may be caused by various organisms and different organisms can also cause the same disease.
