What is a scientific theory? Question 3 options:

a guess or prediction about the natural world with no evidence that some people believe and some people do not believe

a testable guess that predicts how variables are related in an experiment or model system, often expressed as an if-then statement

an explanation of that natural world that has been repeatedly confirmed through observation and experimentation and is accepted by the scientific community

the description of the relationships between observable phenomena

The tubes transporting minerals and water upward are called ?

Hormones are chemical molecules produced by endocrine glands. one such endocrine gland is the thyroid gland, which synthesizes the thyroid hormone, which in turn affects the heart muscles. which two statements describe the probable reason for the function of the hormone? the cells in the heart have specific receptors that allow for the intake of hormones. the heart and the endocrine glands have the exact same types of cells. all cells make the same types of hormones. thyroid hormones show their effect on the heart by means of specialized cells. thyroid cells and cardiac cells have different dna.

Which of the following happened during the precambrian era? the first prokaryotic cells the first eukaryotic cells development of photosynthesis all of the above