What group makes up most of the phylum chordate

Why do some dna fragments move farther than others during gel electrophoresis? a. because their shapes are different b. because they are different types of molecules c. because the samples are different colors d. because their masses are different

The bacteria in the human gut feeds on the food we eat and us break it down for better digestion. what does this exemplify? (a) predator-prey cycle (b) parasitism (c) mutualism (d) a disrupted food chain

Which of the following is true about the introduction of a non-native species to an environment? (a) they usually adapt quickly so they can have a positive affect on the environment. (b) they can disrupt the environment and cause much damage and devastation to native species. (c) they usually become predators in a food chain and to keep prey populations under control. (d) because the native species are better-adapted to the environment, the non-native species always end up dying out.