When a Spirogyra cell is immersed in a salt solution more concentrated than its cell sap, it?
Which of the following is NOT regarded as a pollutant on land or in the air?
The initial volume of water poured into a bag of dry soil was 50ml and the amount that drained through was 35mI. The percentage water content of the fully soaked soil is therefore?
When the original king and queen of termites die, they are replaced by
In demonstrating the importance of mineral elements in plants, the culture bottle must be darkened to?