Question

Give characteristics of class mammalia.

Answer 1

Hint: The animal kingdoms are divided into different phylum. The classification depends on their body structure, habitat they found, shape of the body, mode of respiration, mode of reproduction, and the modification of the body.

Complete Answer:
- The five kingdoms includes; Monera, Protista, fungi, plantae, and animalia. The Monera is divided into bacteria, cyanobacteria, and archaebacteria. Kingdom Protista includes members that are aquatic and have nucleated cells. Kingdom fungi include yeast, moulds, mushroom, etc.

- They are filamentous, have long thread-like structure called hyphae, have a cell wall composed of chitin. The kingdom plantae includes all the plants. They are eukaryotic, autotrophic, composed of cell walls made of cellulose. Lastly, kingdom animalia includes all the animals. They are eukaryotic, heterotrophic, and do not have a cell wall.

- The kingdom animalia is further classified into different phylum that includes; Porifera, Coelenterata, Platyhelminthes, Nematodes, Annileda, Arthropoda, Mollusca, Echinodermata, Hemichordata, and Chordata. The phylum Chordata consists of sub-phyla; Urochordata, Cephalochordata, and Vertebrata.

- Now, Mammalia is characterised under vertebrata. They have many advanced characteristics that separate them from other animals. They are called mammals because of the presence of mammary glands to feed their young one.

- The characteristics of mammals includes; they are warm blooded animals, they are the dominant form of animals found in all habitats, they have neocortex which is a region of brain, the skin of mammals consists of oil glands and sweat glands, they have hairs throughout the body to maintain the temperature according to the environment, they posses different type of teeth, hence they are considered as heterodont, they consists of cervical vertebrae, the skull is dicondylic, they respire through lungs, they consists of 12 pairs of cranial nerves and also comprises of advances diaphragms.

Note: The mammals can give rise to young one but some of them also lay eggs, therefore they are viviparous in nature. The two types of egg laying mammals are echidna and duck-billed platypus.