In this animated activity, learners examine muscle cell contraction and relaxation and consider the role of calcium ions.

Learners read about the mutations that occurred in plants for the successful transition from an aquatic to a terrestrial existence. The classification of plants is based on these adaptive structures.

In this learning activity you'll study the structure of the cell membrane and construct it using the correct molecules.

Learners quiz themselves on the conversion factors within and between the metric, apothecary, and household systems.

In this learning activity you'll use the Empirical Rule to calculate the percentages of data between two data points.

In this learning activity you'll calculate the numeric value of an area when given the z scores.

In this learning activity you'll explore normal distribution and enter values for the mean and the standard deviation of normally distributed data and observe the resulting changes in the shape of the normal curve.

In this learning activity you'll identify and calculate the area under the normal curve specified by given z-scores.

fruit characteristics

4 stages of the plant cycle and photosynthesis