Question 11 (1 point) What prevents backflow of urine into the kidneys? O the internal urethral sphincter
the angle of the ureter
the external urethral sphincter
the mitral valve​

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

The first three phases of the cell cycle are collectively known as (1 point) play audio cellular respiration. telophase. mitosis. interphase.

Which of the following can be reduced by the use of renewable energy sources? a. social costs b. economic costs c. environmental costs d. all of the above select the best answer from the choices provided a b c d