1.How Can You Classify Single-Celled Organisms? Some of the oldest and most common organisms on Earth consist of only one cell. These single-celled, or unicellular, organisms display all of the characteristics of living things. You might think that all unicellular organisms are very similar, but this is not the case. These fascinating creatures are extremely diverse.

What characteristics do you think could be used to classify different kinds of single-celled organisms?

The diagram below represents a marine food web and a process that can harm the human population. each circle represents an organism and the smaller dots inside them represent a toxic substance. what is being represented and how does it harm the population? the diagram represents biological half-life, in which toxins build up in organisms higher up on the food chain, and this can negatively impact humans who consume the organisms and the toxic substance. the diagram represents biomagnification, in which toxins build up in organisms higher up on the food chain, and this can negatively impact humans who consume the organisms and the toxic substance. the diagram represents the process by which different organisms prey upon each other; this can impact the human population by reducing the number of organisms that do not contain the toxin. the diagram represents the way that toxins are metabolized by living organisms, with those at greater trophic levels able to metabolize more efficiently than those at lower levels. this means that those at higher tropic levels are safer for humans to consume compared to the organisms at lower trophic levels.

Identify two examples of chemical reactions that you have encountered during the last week. identify an exothermic and endothermic reaction. explain.

Select the correct answer. which statement applies only to the axial skeleton, not the appendicular skeleton? a. it contains a pivot joint. b. it has muscles attached that work in pairs. c. it contains red bone marrow. d. it possesses fossa for bone articulation. e. it protects the heart and lungs.