必修三unit_4Astronomy_science_of_the_stars精品.pptVIP

* * * * * * * * amphibians live on land and in the water forests 4. What life developed next on land? reptiles appeared dinosaur developed 5.What life developed after forests appeared? mammals on land 6.What life developed after dinosaurs? small clever animals 7. What life developed after mammals? Put the order of development of life into a time line. Insects and amphibians appeared The earth became a solid ball Reptiles appeared The earth was a cloud of dust Shellfish and other fish appeared Clever animals with hands and feet appeared G. Dinosaurs appeared H. Small plants grew on the water I. Plants begin to grow on dry land J. Water appeared on the earth The universe began with a “Big Bang Mammals (including humans )appeared 2 1 3 7 6 5 4 8 9 10 11 12 1.Why was the earth different from other plantes? A . It produce a lot of heat B . The water remained C . Water disappeared D . It was the oldest planet 2. Why was life able to develop on the earth but not on other planets? A. The earth had a solid shape B. The earth didn’t have hameful gases in its atmosphere C. The water stayed on the earth but not on the other planets D. The earth was not too hot and not too cold 3. Why was it necessary for plants to grow before animals? A. Animals need plants to protect them from the sun B. Plants pvovided oxygen for animals to breath C. Animals could hide from hunters in forests D. It was easier for plants to grow 4.What problem is caused by human beings? A. They exists everywhere on the earth B. They caused globel warming C. They find new methods of growing crops D. They enjoy hunting and fishing Fill in the blanks in the following form. Time What happened Big Bang ______ began to form and combine to create stars and other bodies. Atoms Between 4.5 and 3.8 billion years ago ●Dust settled into a solid and ______ globe. ●The earth exploded to produce its ___________. ●The continued ________ of water allowed the earth to dissolve harmful g