14. amphibians have adapted to the challenge of distributing oxygen more
efficiently to all cells by
a. developing a double-loop circulatory system
b. breathing more quickly
c. breathing only out of water
d. developing a one-way respiratory system

Which of the following statements are true chromosomes make up genes

Why are carbon dioxide concentrations expected to increase? a carbon dioxide concentrations are expected to increase, because fossil fuel burning is expected to increase b. carbon dioxide concentrations are expected to increase, because of an increase in agriculture. c.carbon dioxide concentrations are expected to increase, because more land will have to be cleared for increasing populations and agricultural use. d. all of the above select the best answer from the choices provided mark this and return save and exit next submit submit

Draw a simple labelled diagram if a collenchyma tissue