All vertebrate embryos have a notochord, or a long rod that runs through the body just below the nerve cord. as the embryo develops, only jawless fish retain the notochord. what does this indicate about the evolution of vertebrates?

Dr. kaylan is an ecologist who studies bird behavior. she sets up an experiment to test which type of food crows are most likely to eat when given a choice between walnuts, corn, and sunflower seeds. to perform her experiment, dr. kaylan places three food bins in an area frequented by cows. each bin contains one of the three food types. then, she measures how much of each food type is eaten every day for a month and summarizes the results of her experiment in the pie chart below. based on her results, dr. kaylan concludes that crows choose to eat corn more frequently than other food sources because it has a higher nutritional value. what is a reasonable alternate conclusion that can be drawn from dr. kaylan's data

Ausable water source is one that can be used by humans for drinking or agriculture. identify the water reservoirs as usable or unusable based on their current state. oceans rivers glaciers freshwater lakes groundwater

One important development during the 3rd trimester that will insulate the infant against changes in temperature is a. the deposition of fat under the skin b. the closing of the septum between c. the atria of the heart d. the beginnings of lung functioning e. the beginnings of light and sound sensing