2 chains and 4 nucleotides
The law of conservation of matter is that matter cannot be destroyed, it can only be changed. Really, any cycle is an illustration because, in cycles matter is not destroyed, only changed.
In simple words: The hydrologic cycle illustrates the law of conversation of matter through the matter in this cycle not being destroyed, only changed.
Answer:
It is "The opening of flask is pointed in an unsafe direction"
Explanation:
The students were there in the lab to perform practical without obeying the safety rules. The most reasonable basis for teacher's warning here, in this case, is the flask which is pointed in an unsafe direction. It is not specified whether the flask is containing any chemical or not but even if it is empty, it might just fall and break and create injury to anyone present in the lab because, the students are also not wearing proper laboratory wear in accordance to the safety rules which include lab coats, gloves, eyewear, etc. Also, some Students have not tied their hair and more importantly the flasks carrying liquids are not labeled. All of these things might end up in a critical situation for which the teacher warned students about it all.
Charles Darwin noticed that among the same species there were variations in traits based upon geographical location. These changes may have evolved from climate differences, predator/prey relationships and food sources. This particular experiment was intended to duplicate natural selection by demonstrating the concepts with artificial selection. The result was that over time, new traits could be bred for. Although there may be more than one correct answer here, the best answer is the first; desirable traits can be selected and bred in offspring.
Answer:
the answer is cytokinesis