Arthropods are joint legged animals. Spiders, crabs, pill bugs, centipedes, and millipedes are examples of the many types of arthropods. Which of these arthropods are most closely related?

Using a light microscope, a student identified the following characteristics of four organisms found in a sample of pond water. Based on the observations of the student, which organisms most likely belong to the taxonomic group for bacteria?

The diagram shows a dichotomous key and a picture of a fruit. According to the key, the fruit comes from which species of tree?

Frogs and toads belong to the order Anura. The smallest organism in this order is about 7 millimeters long, while the largest member is about 30 cm long. Which of these lists best describes this order?

A cladogram is shown below. All the animals to the right of the hagfish would have the common characteristics of -

While visiting a national park, a student encounters an unfamiliar organism in a damp area near a body of water. The student notes that the organism is about 10 cm long, has four legs, and has a tail. The organism is black with small white spots on its smooth, moist skin. It also appears to have an internal skeletal system. To which class does the organism most likely belong?

This dichotomous key can be used to identify some conifers. Based on the key, which of these best describes the leave and cones of the longleaf pine?

Simple leaves have a single leaf on a petiole, or stem, while compound leaves have more than one leaflet on a petiole. This unknown leaf can be identified using the dichotomous key. Which tree does the unknown leaf come from?

The classification of four trees are shown in the table. Which two trees are most closely related?

A student used a microscope to study four members of the phylum Ciliophora. Members of this phylum move when propelled by hundreds of tiny cilia. Although these organisms belong to the same phylum, they are classified as different -

The relationship among different orders of millipedes are shown in the cladogram. Based on this cladogram, which statement best describes relationships among millipede orders?

A dichotomous key for identifying fish is shown. Based on this key, which two fish have eyes located on either side of their head and are not spotted?

Many tree frog populations are threatened due to habitat loss. In an effort to promote conservation, tree frogs may be bred in captivity. A zoo acquired male and female tree frogs from two different populations. In the zoo, the tree frogs were able to successfully mate within their own population, but breeding attempts between the two populations were unsuccessful. Based on this information, which statement correctly describes the relationship between the two populations of tree frogs?