OCT 13-17-VERTEBRATES Animals Science Grade 6

Vertebrates

1. Vertebrate & Invertebrate Animals

2. GENESIS 1:21 So, God created the great creatures of the sea and every living thing with which the water teems and that moves about in it, according to their kinds, and every winged bird according to its kind. And God saw that it was good.

3. Vertebrates Animals differ in many ways. Some animals live on land, and others live in water. Some animals can fly, and others walk or jump. One thing that all animals have in common though is the way they carry out certain functions to survive. For instance, all animals need food and air.

4. Animals vary in so many ways, which is why there is a need to group or classify them. Chordates are animals with a notochord. The notochord is a flexible, rod-shaped cartilage found inside the embryo of a chordate. Chordates are divided into two subgroups: vertebrates and invertebrates. In most cases, the notochord of a vertebrate is replaced with a vertebral or spinal column.

5. The Vertebrates: Animals with a Spine Vertebrates are groups of animals that have a backbone or a spinal column. They only comprise approximately 45 000, or 3% of the known species in the world. They also have three distinct structures: the spinal cord, the vertebrae, and the notochord. The spinal cord contains delicate nerves. Consequently, the presence of the vertebrae and the notochord are very important for support and protection. Most vertebrates have an advanced nervous system, muscles, and skeletons, which allow them to move around efficiently and perform complex actions.

6. Cold-Blooded Animals: Fishes, Amphibians, and Reptiles Cold-blooded animals are groups of animals that cannot maintain their body temperature. This means that their body temperature depends on the temperature of their outside surroundings. They move around during the day under the shade or under the sun just to warm up or cool down. Fishes, amphibians, and reptiles are cold-blooded animals.

7. Fishes have been around for 500 million years already. They are aquatic animals that have fins and tails, which they use to swim. They breathe through their gills. There are three groups of fishes: jawless, cartilaginous, and bony.   Jawless fishes are the oldest group of fishes. They do not have scales and jaws. Among the species of jawless fish, only the lamprey and the hagfish remain.

8. Cartilaginous fishes are fishes that have cartilage as their skeleton. These fishes are covered with hard scales. They also have hard and sharp teeth. They lack a swim bladder, so they must swim to keep afloat. Some examples of cartilaginous fishes are sharks, stingrays, swordfishes, and skates. Sharks are huge, fast, and have very sharp teeth that they use to rip their prey apart.

9. Bony fishes are the largest group of fishes. They have real bones as their skeleton. These fishes also have a swim bladder , an organ that gives them the ability to float. Tilapia, milkfish, mudfish, tuna, catfish, and trout are examples of bony fishes.

10. Amphibians are a group of animals that can stay both on land and in water. Most amphibians are covered with slimy, moist skin. They absorb oxygen through their skin, and oxygen is absorbed better when the skin is moist. Amphibians live in two kinds of habitats during their lifetime. When they are young, they spend their lives in water. They live on land once they become adults. Because amphibians live their young lives in the water, they use gills to breathe. These gills will develop into lungs later on so they can breathe air.

11. Amphibians undergo a fascinating life cycle. of amphibians.   There are three groups These are the anurans (frogs and toads), salamanders (newts), and caecilians .

12. Reptiles are a group of animals that have lungs to breathe, and dry, scaly skins in some areas or all over their bodies. Some scales are hard, soft, large, or small, but they are mostly made of keratin , the same substance that forms our hair and fingernails. The turtle's shell and the crocodile's plates are covered with hard, large shells called scutes . Snakes also have scutes in their abdomen. At present, the most common examples of reptiles are alligators, crocodiles, snakes, lizards, tortoises, turtles, geckos, and iguanas.

13. Warm-Blooded Animals: Birds and Mammals Warm-blooded animals are groups of animals that can regulate their internal body temperatures. When it is hot, these animals regulate their body temperatures through sweating or panting. They also have hairs, furs, or feathers to help keep them warm. Birds and mammals are examples of warm- blooded animals.

14. Mammals are also warm-blooded animals. They are classified after the female's mammary glands because they are the only animals that produce milk to feed their young. They also have hair or fur, as well as lungs to breathe. Most mammals are viviparous. They develop and nourish inside the placenta within their mothers' bodies. Once the embryo is fully developed, the mother gives birth to its young. Mammals are categorized as primates, marsupials, rodents, cetaceans, seals, and monotremes.  

15. Rodents are gnawing animals. They have huge incisor teeth to gnaw food and wood, as well was bite their predators. Examples of rodents are rats, squirrels, chipmunks, porcupines, and beavers.   Cetaceans are marine mammals such as whales, dolphins, and porpoises. Because they breathe with their lungs, they must come to the surface to breathe air through their blowholes, which are their nostrils on top of their heads. Whales can be grouped into toothed whales and baleen or toothless whales.

16. Monotremes are egg-laying mammals, such as the duck-billed platypus and echidna (spiny anteater). Monotremes have only one hole or one rear opening in their body for reproduction and excretion. They have mammary glands and give milk to their young. They are found in Australia and Papua New Guinea.

17. Most mammals are beneficial. Carabaos, for example, help farmers plow the rice fields or pull heavy carts. Horses also help in pulling heavy loads and transport humans from one place to another. Cows and by goats give meat and milk to people. Their milk can be processed into dairy products such as butter or cheese. Pigs are raised for their pork, and deer are hunted for their venison (deer meat). Cats, dogs, and rabbits are kept as pets at home.

18. Thank you for listening!