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Hello, class! Welcome to a new Natural Science lesson.

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In this case, Natural Science, Unit 2, Lesson 3,

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Groups of Vertebrates.

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Remember, vertebrates are those animals

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with a backbone and a skeleton inside of them.

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In the mirror world, there are five groups of vertebrates.

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Amphibians, reptiles, birds, mammals and fish.

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Remember, we can classify these groups into

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warm-blooded, like birds and mammals,

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or cold-blooded, like amphibians, reptiles and fish.

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Next.

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Next.

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Vertebrates are covered by...

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Mirror world.

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Mammals are covered by fur.

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Birds are covered by feathers.

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One curiosity of birds.

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In the spring, peacocks display their beautiful feathers.

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Mirror world.

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Scales.

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Reptiles and fish are covered by scales.

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Or skin.

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Amphibians and some mammals are covered by skin.

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Next.

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Reproduction.

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Remember that vertebrates can be viviparous or oviparous.

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Mirror world.

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Mammals are viviparous.

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Amphibians, reptiles, birds and fish are oviparous.

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One curiosity of mammals is that female mammals produce milk to feed their babies.

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Next.

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Vertebrates live on land or in water.

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Next.

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Vertebrates breathe with lungs or with gills.

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With lungs.

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Birds, mammals and reptiles breathe through lungs.

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On the other hand, fish breathe with gills.

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And what happens with amphibians?

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Both.

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Baby amphibians breathe using their gills.

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Adult amphibians use their lungs to breathe.

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Next.

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You can watch this video on YouTube.

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You have the presentation in our Aula Virtual de Duca Madrid.

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Here you have some examples of mammals.

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Here you have some examples of reptiles.

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Remember that snakes have no limbs so they slither to move around.

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Chameleons use their camouflage to defend themselves from predators.

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These are some examples of amphibians.

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These are some examples of birds.

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Penguins are birds but they cannot fly.

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They can't swim.

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That's all. Thank you for listening.