1.3 To indicate differences among vertebrates

Natural sciences

Ecosystems and the environmental balance

Educator section

Memorandum

Assignment 6:

a. They hibernate or sleep or remain very inactive.

b. They develop cold shivers and begin to shiver in order to raise the body temperature.

c. They develop a fever and begin to sweat in order to lower the body temperature. They become tired more quickly and rest a lot.

d. The mammals care for their young until they are strong enough, but this is not done by reptiles. The young are not cared for and must take care of themselves.

e. Oviparous: lay eggs outside of the body Viviparous: the young are born alive

f. The human is the most highly developed being and its physical, emotional and mental development therefore take much longer than that of other mammals.

Leaner section

Content

Activity: to indicate differences among vertebrates [lo 2.1]

(i) Other differences between Vertebrates

Animals also differ from one another with regard to what they eat, the organs used for movement, their ways of reproduction and the care of their young.

Ø Mammals

All animals that feed their young with milk are called mammals. Mammals care for their young until they are strong enough to be able to survive on their own. They also are warm-blooded animals, which means that their body temperature must remain more or less constant all the time.

Most mammals are land animals, such as ungulates (horses); predators (lions); rodents (rats); insectivores (hedgehogs) and anthropoids (baboons). A few species also live in the water, such as the dolphin, the whale and the seal.

Ø Reptiles

Reptiles are cold-blooded animals, which means that their bodies have more or less the same temperature as that of the surrounding environment. If it is too hot, for example, lizards will seek shelter in the shade. Reptiles do not suckle their young. As soon as the young are born, they go their own way and take care of themselves.

Assignment 6: Group work

Discuss the following questions in your groups and then answer them in full sentences:

1. What do many reptiles do in the winter when it becomes very cold?

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2. What happens to mammals when their body temperature drops too low? Why does the body display such a reaction?

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3. What happens to mammals when their body temperature rises too high? How is the temperature restored?

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4. How does reproduction in mammals differ from that in reptiles?

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5. Most lizards are oviparous and most mammals are viviparous. Find out what this means and explain the difference.

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6. Humans suckle their young the longest. Why is this so?

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SUMMATIVE: 10

Assessment

Learning Outcome 2: The learner will know and be able to interpret and apply scientific, technological and environmental knowledge.

Assessment Standard 2.1: We know this when the learner recalls meaningful information.