protostome development

Derived character shared by two or more taxa on a tree.

the answer is C on the pretest: A SYNAPOMORPHY for Plato users

It's a trait common in a single monophyletic group,but not generally found outside of that group.

A synapomorphy is a shared derived trait among a group of organisms that indicates their common evolutionary history, such as feathers in birds. A homologous trait is a trait shared among different species due to a common ancestor, such as the pentadactyl limb structure in vertebrates. Synapomorphies are specifically used in phylogenetic analysis to determine relationships among organisms, whereas homologous traits can represent a broader concept of shared ancestry.

Animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestors.

Generating internal heat to moderate body temperature, e.g., modern birds and mammals. Warmblooded.

In cladistic analysis, a characteristic that arises as a lineage of organisms evolves over time is called a derived trait or synapomorphy. These traits help define clades within a phylogenetic tree by marking unique evolutionary advancements shared by a common ancestor and its descendants.

Mesquite is in the family Fabaceae, also known as the pea or bean family. At one point in the history of plant classification all family names were standerized to all end in "aceae." Before that, the Fabaceae was known as the Leguminosae. Because this is the third most abundant plant family in the world, is very wide spread, and is therefore imortant to people, Leguminosae was chosen to be an exception to the "aceae" rule. Although it was given its new "aceae" name, it is still considered correct to use the old name and you will see it used from time to time. Also, it is useful to use the name Leguminosae because it describes the most prominant identification feature and synapomorphy of the family, which is the leguminous fruit. All members of the Fabaceae are legumes. The word "legume" describes the type of fruit and is the name of plants that bear leguminous fruits.

I'm sure you didn't need to know all of this, but the Fabaceae is my favorite plant family!

Most cats, including domestic cats and big cats like lions and tigers, have retractable claws. This feature allows them to keep their claws sharp by keeping them protected when they're not in use, and also helps them to silently stalk and hunt prey.

In some ways yes and in some ways no. So humans are animals.