'The endocrine system<span> is made up of glands that produce and secrete hormones, chemical substances produced in the body that regulate the activity of cells or organs. These hormones regulate the body's growth, metabolism (the physical and chemical processes of the body), and sexual development and </span>function' According to Google.
<span>Excess nitrogen is brought in the pond from the fertilizer, which are ladden in nitrogen and phosphorous, and rain water or running water takes that nitrogen to the water bodies.Bacteria must have come from the sewage disposal in the pond. Sewage is rich in organic material and allows proliferation of bacteria, which is taken to the pond when the sewage is disposed in the pond.</span><span />
A thermal conductivity of 0.1213 W/mK, for pine was the product of the HFM measurement. ... This change in construction material can be attributed to the thermal conductivity of soft woods being approximately 1/7 that of brick.
Neither matter or energy is created or destroyed, it is simply reused.
Answer: multi-cellular bodies
Explanation: All animals are multi-cellular. This means that they are made up of many cells/cellular systems. Single-celled organisms, on the other hand, are not considered animals. Those would mostly be too tiny to see without the aid of a microscope tool. The other answer choices would not fit, because not all animals have bones (endoskeletons or exoskeletons). Also, only some animals are cold blooded, which is what the last answer choice has to do with.