Bio lab 1201
19th of April 2014
Report About Vertebrates Three Classes Aves, Reptilia and Mammalia
Chordates are animals with backbones, and it is known that animals with backbones are not only the most complex and complicated groups of animals, but also really highly devolved. They also have interior skeletons and have bilateral symmetry. They have more advanced brains. Organism that belongs to phylum Chordates have to have four features, which include a notochord, there is a semi-flexible rod which not only provides structural support, but also is there as an anchor for the animal's large body muscles and the post-anal tailin, a hollow nerve cord in the dorsal side of the body, a respiratory system that contains either lungs or gills positioned near by the throat, where a chordate takes in oxygen and gets rid of carbon dioxide, in either their adult stage or embryonic stage. The most common characteristic for the Phylum Chordates is that their bodies are almost every time shown with segmentation -“Phylum Chordata” Animal groups of chordate phylum include birds, amphibians, reptiles, amphibians, mammals and fish and that is the animal phylum that people are most familiar with. It also includes humans and other vertebrates, but not all of the animal groups of Chordate phylum is Vertebrates. However, the phylum Chordates is divided in three subphylum, Vertebrates, Tunicates and Lancelets. This lab report will focus on Vertebrates, which are most familiar phylum, the largest subphylum, since it has eight classes and it is the most widespread spreading on the earth. The characteristics of Vertebrates are that they have an internal skeleton of bones for protecting the nerve cord and serves as it is as the axis of the internal skeleton, large bodies, and the cartilage which provides not only features that are mentioned for phylum Chodate, but also surface for muscle attachment, support, and a cranium protecting the brain. (McRae, 2007). In this lab report I will compare, define and contrast about three classes of Vertebrates; Aves, Reptilia and Mammalia.
The class Aves, with common name birds evolved from reptiles, are tetrapod and the anterior pair of limbs are modified to wings, they have a four-chambered heart and the breastbone is puffed-up to help and support muscles for flying. , Tetrapod means that they have four limbs, almost all of them are coved with a scaly, and have waterproof integument. Bird’s main way of movement is flying and their bodies are covering with feathers and most of feathers are adjusted not only to help them fly and but also to help them to regulate body temperature (McRae, 2007). They live in many types of habitat and have evolved a diversity of forms and they use their wings not only to fly from place to place, but also to look for food. When they find food, they use the kind of beak or bill that all bird have, to help them find out what type of food it eats. Birds eat cracking seeds, insects, worms, berries, fruit, flower nectar, nuts, tree sap, buds of trees and shrubs, fish, small animals and eggs. (“What do Animals eat”). All the different species of bird’s needs different types of natural habitat, therefore, the habitat birds search for is rich in resources, which could be heathland, woodland, forest, rainforest, wetland such as beaches, estuaries, rock platforms and headlands (“Natural Habitats of Birds”). Both male and female birds have a cloaca, which is one opening, also known as vent that serves as the exit for their digestive, urinary and reproductive systems. Reproduction of birds can be sexually, using internal fertilization, with a process known as copulation. The male bird fertilizes the female with his sperm form his cloaca to the female cloaca (Mayntz).
The class Reptilia, whit more common name of reptiles, are also tetrapod, with really effective lungs, a middle ear and majority of them have a 4-chambered heart (McRae, S.B) Different reptiles have