Grade 7 Life Science students explore how amphibians and reptiles evolved adaptations that allowed vertebrates to transition from aquatic to terrestrial life, covering key traits such as moist skin, lung respiration, ectothermy, and egg structure. The lesson compares amphibians like frogs and salamanders with reptiles like turtles and snakes, examining how each group is suited for life on land. This is Lesson 2 of Chapter 13 in the Grade 7 Life Science textbook.
Section 1
Amphibians Adapt Between Water and Land
Amphibians evolved to live partly on land with adaptations like legs and lungs. They maintain moist skin for breathing, lay shell-less eggs in water, and undergo metamorphosis from aquatic larvae to land-dwelling adults.
Section 2
Reptiles Conquer Dry Environments
Reptiles evolved tough, scaly skin and shelled eggs that allow them to thrive in hot, dry places. Their waterproof skin and fully-developed lungs enable complete independence from water throughout their entire lives.
Section 3
Ectotherms Regulate Temperature Through Behavior
Amphibians and reptiles are ectotherms whose body temperatures change with their environment. They use behaviors like sunning themselves to warm up or finding shade to cool down, helping them function optimally.
Section 4
Vertebrates Transform Body Structures for Land Living
Fish evolved into land vertebrates through adaptations like developing legs instead of fins, changing gills to lungs, and modifying sensory organs to detect stimuli in air rather than water.
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Section 1
Amphibians Adapt Between Water and Land
Amphibians evolved to live partly on land with adaptations like legs and lungs. They maintain moist skin for breathing, lay shell-less eggs in water, and undergo metamorphosis from aquatic larvae to land-dwelling adults.
Section 2
Reptiles Conquer Dry Environments
Reptiles evolved tough, scaly skin and shelled eggs that allow them to thrive in hot, dry places. Their waterproof skin and fully-developed lungs enable complete independence from water throughout their entire lives.
Section 3
Ectotherms Regulate Temperature Through Behavior
Amphibians and reptiles are ectotherms whose body temperatures change with their environment. They use behaviors like sunning themselves to warm up or finding shade to cool down, helping them function optimally.
Section 4
Vertebrates Transform Body Structures for Land Living
Fish evolved into land vertebrates through adaptations like developing legs instead of fins, changing gills to lungs, and modifying sensory organs to detect stimuli in air rather than water.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter