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.
Symbiosis in lichens is the mutually helpful symbiotic relationship of greenalgae and/or blue-green algae(cyanobacteria) living among filaments of a fungus, forming lichen. The algaeor cyanobacteria benefit their fungalpartner by producing organic carbon compounds through photosynthesis
Answer: Vascular smooth muscle cells.
Explanation:
Vascular smooth muscle cells are the contractile tissues which regulates flow blood and pressure of the blood by vasoconstriction (contraction) and/or vasodilatation (relaxation).
Vasoconstriction is the contraction of the blood vessels to increase tge pressure of the blood.
Vasodilatation is the relaxation of the blood vessels which results in a decrease in blood pressure.
