Why does my cat keep putting her butt up and meowing but she isn't in heat

When does the circulatory system work with the respiratory system? a. during blood cell formation b. during cellular respiration c. during intestinal digestion d. during a viral infection

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

Consider the following reaction: 2h2 + o2 —> 2h2o a) what are the reactants in this reaction? b) what are the products in this reaction? c) how many molecules of oxygen are used in this reaction?