What is the basis of the researchers' new theory
A: They performed mathematical calculations and determined that dinosaurs must have had four chambered hearts.
B: They found a fossil of an entire dinosaur end reviewed the arteries and veins flowing from and to the heart.
C: They found a fossil of a dinosaur's heart and discovered it had four chambers and one aorta.
D: They viewed a fossil of a dinosaur's heart and discovered that it had two aortas.
A: They performed mathematical calculations and determined that dinosaurs must have had four chambered hearts.
B: They found a fossil of an entire dinosaur end reviewed the arteries and veins flowing from and to the heart.
C: They found a fossil of a dinosaur's heart and discovered it had four chambers and one aorta.
D: They viewed a fossil of a dinosaur's heart and discovered that it had two aortas.
举一反三
- The main idea of the text is_____. A: the Dromaeosanr's skeleton was found B: fossil dinosaur reveals body covered in feathers C: modern birds evolved from dinosaurs D: a recent new invention
- The dinosaur’s eggs are found by explorers in the _______
- He made a firm ____ to give up smoking and drinking as soon as he discovered that he had a heart trouble.
- The power of the female heart remains undiminished between the ages of 18 and 70 probably because _________. A: women almost lose no contractile muscle cells in the walls of their hearts B: women's oestrogen has a protective effect on their heart C: the size of their heart chambers is different from men's D: the thickness of the female heart's muscular wall is different from men's
- Aristotle, the Greek philosopher, had a theory that the heart was a blood-cooling mechanism.