[Solved] The probabilistic model allows the E(y)values to fall around the regression line while the actual values of y must fall on the line. Plant Material: Organic compounds derived from plants, including leaves, stems, roots, and flowers, involved in various ecological cycles. Microorganisms: Very small, often single-celled organisms that can be bacteria, fungi, viruses, or protozoa, not visible to the naked eye. Iron Formation: A sedimentary rock consisting of alternating layers of iron-rich minerals and silica or carbonate, typically formed in Precambrian seas. Seawater: The saltwater that makes up the oceans and seas, covering more than 70% of the Earth's surface, containing various salts and life forms.