Question

What is the difference between dependent and independent variable ?

What is phytophthora I destiny and how it change u.s history ?

Answer 1

1. Variable is a term used for any factor that changes. When this variable is now changed intentionally to observe its effect on the other feature, it is called independent variable.

This intentional change in independent variable is expected to change the another variable, which is called dependent variable. For example, if we study the impact of minerals on the growth of an individual, the mineral is an independent variable whereas growth of an individual is a dependent variable ( because it changes with the change in the concentration of minerals).

Similarly during the study of impact of drug on a disease, the drug is an independent variable whereas disease is a dependent variable.

2. Phytophthora infestans is known for causing Late Blight disease in potatoes and was responsible for potato famine in Ireland. It changed the course of history in the USA due to huge immigration of Irish people to US to avoid starvation due to Late Blight disease in potatoes ( potato was the staple food of Irish people). It is because of this Phytophthora Infestans, that eleven percent of US population is Irish. US was a young country at that time and Irish people didn't face any difficulty during immigration.

This great famine occurred between 1845 to 1852 and changed history of both Ireland and US.