How can one easily discern the renal cortex from the renal medulla on a microscopic slide?

Which of the following is an oxidation-reduction reaction? (pictured below)

Asolution of an enzyme and a substrate was placed in a water bath and the temperature of the reaction was raised gradually. the graph shown was plotted at the end of the experiment. what can be concluded from the graph? a) temperature has no effect on the activity of the enzyme. b) the effect of temperature on the enzyme is unpredictable. c) the enzyme shows increased activity up to a certain temperature. d) the activity of the enzyme is inversely proportional to the temperature.

Hemoglobin is a proton that carries oxygen around the body what is hemoglobin made from