Environmental science enthusiasts show what they know at the end of the year by taking this full-fledged final exam. They answer multiple-choice, graph interpretation, and essay-analysis questions, 73 of them in all. Topics range from...

In this cell reproduction worksheet, learners complete a crossword puzzle with 43 questions about mitosis and meiosis. They compare and contrast the two processes.

Some genetic conditions occur without being inherited. The distinction becomes the focus of the lesson. It details the process of cell division that results in trisomy on various chromosomes. A worksheet highlights the results including...

Scientists found fossils of plants more than 420 million years old—but plants existed for up to 100 million years prior to these fossils. Learn about the importance of plants to the entire planet. Viewing a presentation helps scholars...