Which of these is not a primary plant macronutrient?

oxygen

potassium

phosphorous

nitrogen

What occupation did muhammad have before the first revelation

Amylase becomes denatured at a temperature of 80°c. during an experiment to study the effect of varyingtemperature on enzyme activity, amylase’s reactivity with starch was measured at body temperature (37°c), andthen again at an increased temperature of 42°c. how would this increase in temperature affect the experiment

Crossing over is a method of (blank)?