Natural Sciences Grade 7 Term 1: Life and Living Biodiversity (PPT 3)

Diversity of Animals: Vertebrates Topic 2 Biodiversity Diversity of Animals: Vertebrates Natural Sciences – Grade 7

Classifying the Animal Kingdom Animals can be sorted or classified into two smaller groups: vertebrates and invertebrates One of the simplest and easiest ways of determining what class of vertebrate an animal belongs to is by looking at what covers their body. There are exceptions to many of these, but as a generalization, this will help to organize the vertebrate groups. Fish = scales; Amphibians = smooth or bumpy skin; Reptiles = scales; Birds = feathers; Mammals = fur and hair Some of the other differences amongst the groups include homeostasis (warm vs. cold-blooded), numbers of chambers in the heart, reproduction, brain functions, mobility and sensory organs. Natural Sciences - Grade 7 3

Natural Sciences - Grade 7 Vertebrates Animals with a backbone. Belong to Phylum Chordata There are 5 classes of vertebrates: fish amphibians reptiles birds mammals Natural Sciences - Grade 7 4

Natural Sciences - Grade 7 Vertebrates: fish Fish are aquatic. They are cold-blooded organisms that live in fresh or saltwater. Fish have gills instead of lungs. They usually have scales, fins and a tail. Aquatic = lives in water Cold blooded = they cannot maintain their own body temperature. They are reliant on the temperature of their environment. Natural Sciences - Grade 7 5

Natural Sciences - Grade 7 Vertebrates: fish Cold-blooded = this describes organisms that cannot control their body temperature and so take one the temperature of their surroundings. Natural Sciences - Grade 7 6

Why is this vehicle called “amphibious”? Answer: the car can drive on land and on water, like an amphibean. Natural Sciences - Grade 7 7

Vertebrates: amphibians Amphibians are cold-blooded organisms. They include frogs, toads, newts and caecilians. Most amphibians have four legs and can live on water and on land. We say that they are amphibious. They undergo metamorphosis from a larval stage. Metamorphosis = the process of change in some organisms from an immature form to an adult which is different in appearance. Natural Sciences - Grade 7 8

Vertebrates: amphibians (frog) Natural Sciences - Grade 7 9

Vertebrates: Reptiles Reptiles are cold blooded. They are found in almost every habitat in the world, except for the Antarctic. They usually have four legs and are covered in scales. There are some exceptions, e.g. snakes do not have legs and certain lizards do not have legs. Natural Sciences - Grade 7 10

Vertebrates: Reptiles (lizard) Natural Sciences - Grade 7 11

Natural Sciences - Grade 7 Vertebrates: Birds Birds are warm blooded organisms that lay eggs. They have feathers, wings and a beak. They have two legs that are covered in scales. Most birds are able to fly, although there are some that cannot fly. Birds are found in ecosystems across the world. Warm blooded = these organisms can maintain their own body temperature irrespective of what the outside environment temperature is. Natural Sciences - Grade 7 12

Natural Sciences - Grade 7 Vertebrates: Birds Natural Sciences - Grade 7 13

Natural Sciences - Grade 7 Vertebrates: Mammals Humans belong to the class of mammals. There are many different types of animals in this group. They are able to live in almost any habitat. Some mammals are adapted to walking, some to running, others to flying and some others even to swimming. Natural Sciences - Grade 7 14

Vertebrates: Mammals (rat) Natural Sciences - Grade 7 15