What two body systems will work together to provide cells with energy? A. Excretory and Digestive, because the nutrients from the digested food will be sent to the excretory to be delivered out as waste products.

B. Digestive and Muscular, because the nutrients from the digested food will be used immediately by the muscles for energy.

C. Respiratory and Excretory, because the oxygen will be transported to the cells so that wastes can be delivered out as a waste production.

D. Digestive and Cardiovascular, because the food will be broken down and nutrients will be sent in the bloodstream to the cells for use.

The correct answer for the first question would be B) the respiratory and circulatory systems.

Respiratory system is a set of organs which help in exchange of gases in the body. They bring oxygen from outside into the body and release carbon dioxide from inside the body to outside world. The exchange of the gases takes place at alveolar site (or gills in aquatic animals).

The circulatory system then carries this oxygen (mixed in blood) from gas exchange site to all the cells of the body. In addition, it also brings carbon dioxide (waste product of cellular respiration) from all the cells to the gas exchange site (respiratory system).

The correct answer of the second question would be C)the digestive and circulatory systems.

Digestive system helps in breaking down of macro-molecules (such as starch, polypeptide, fats) into smaller units (such as glucose, fructose, amino acids) as well as absorption of the same.

Nutrients from the absorptive site (usually small intestine) are then transported to the entire body with the help of blood through capillaries and arteries that is, circulatory system.

Explanation:

they each offer a fresh glut of resources to the organisms that can arrive and exploit them. as individuals and new species continue to appear, they actively and passively alter the environment. competition for shared resources increases, local abiotic and biotic conditions shift, and the relative abundances of species change accordingly. the process is called ecological succession, and it is one of the earliest and most well-known concepts in ecology.

frogs. the lower the ph the higher the acid content. frogs have the highest tolerance in this scenario.