Anas Zoology

(Image Source:  https://en.wikipedia.org/wiki/Peafowl ) First let us understand the terms peacock, peahen and peafowl. Peacock and Peahen are collectively known as peafowl. This means peafowl can be used to address either a male or a female.  Peacock is the male peafowl. Peahen is the female peafowl. There are 3 types of Peafowls in the world and they are: Indian Peafowl Green Peafowl  Congo Peafowl (Image Source:  https://www.animalspot.net/peafowl ) 1) Indian Peafowl: It is a peafowl species native to the Indian Subcontinent. Sexual dimorphism is seen. Peacocks are brightly colored while peahens have a dull color. Peacocks are iridescent bluish-green in color while peahens are dull brownish-green in color. The most remarkable difference between the two is the tail feathers. Peacocks have long tail feathers while tail feathers of peahens are short.  Indian Peacock (Image Source:  https://en.wikipedia.org/wiki/Indian_peafowl#/media/File:Peacock,_East_Park,_...

  (Image Source:  https://scopeblog.stanford.edu/2013/08/04/image-of-the-week-botryllus-organism/ ) The Urochordata also known as Tunicata is a part of Phylum Chordata. General Characteristics of Urochordates: They are marine and sedentary. Their body is enclosed in a test/tunica. Notochord is present in the tail region in larvae (hence urochordate) and disappears in adults. Alimentary canal is complete and are ciliary feeders. Respiration is through numerous gill slits (Stigmata) which opens into the ectoderm lined cavity, the atrium. They show open circulation. They have special corpuscles, vanadocytes (except in Herdmania ) to extract vanadium from sea water and store it in blood vessels. Dorsal tubular nerve chord appears only in larval stage, which in adults is replaced by a single dorsal ganglia. Sense organs are in the form of receptors. Excretion is by nephrocytes, pyloric gland or neural gland. Asexual reproduction is by budding. Mostly hermaphrodite. Their developmen...

Taxonomical categories/ranks represents the group of organisms sharing common characteristics/features. Example: Insects represents a group of organisms sharing common features like three pair of jointed legs. Taxonomical categories include Kingdom, Phylum (for animals) and Division (for plants), Class, Order, Family, Genus and Species. Kingdom is the highest taxonomical category and species is the lowest taxonomical category. To place an organism in a particular taxonomical category one must have a knowledge of the organisms characteristics.  Taxonomical Categories: 1) Kingdom: It is the highest taxonomical category. There are 5 Kingdoms: Animal, Plants, Fungi, Protista and Monera Different organisms are placed in different kingdoms based on their characteristics. Example: a) Organisms that are multicellular, do not possess chlorophyll, cell wall is absent in cell, and are eukaryotic are placed in the Kingdom Animalia. e.g. Human, fishes, frog etc. b) Organisms that are multicellu...

 Animals are metazoans that differ from plant in number of characteristics like absence of plastids, cell wall and central vacuole. There are around 1.2 million known species of animals, but scientists estimate there are closer to 8.7 million species on earth. they show great diversity in shape, size, colour, habits, habitat, structures etc. CHARACTERISTICS OF ANIMALIA: They are multicellular consumers of the ecosystem. They are made up of eukaryotic cells and have no cell wall, plastids, central vacuole and photosynthetic pigments. Lower animals exhibit cellular or tissue level of organization and higher animals have organ system level of organization. Mostly free living and some are fixed (sponges and several coelenterates). They take food by ingestion i.e. holozoic in nutrition and digestion takes place in an internal cavity. Some forms have absorptive nutrition and their digestive cavity is absent. The undigested food is removed by egestion.  They have muscle cells (for co...

  It is the arrangement of body parts on two sides of main axis of body. animals can be categorized on the basis of body symmetry as follows: ASYMMETRICAL  : Body is highly irregular that it cannot be divided into two similar parts by any plane e.g. snails, sponges,  Amoeba SYMMETRICAL :  The body can be divided into two similar parts by one or more planes (a) Spherical / Universal Symmetry :  The body is like a ball and can be divided into two equal parts by any plane passing through the centre of the body e.g.  Volvox,  some corals. (b)  Radial symmetry :  The body is in the form of a flat or cylinder (tall). It can be divided into equal halves by any plane passing through the centre from top to bottom e.g. some sponges,coelentrates, echinoderms. Their types are as follows: (i)   Tetramerous Radial Symmetry :  Body parts are arranged in 4 or multiple of 4 e.g. Jellyfish (ii)   Pentamerous Radial Symmetry :  Bod...

 KINGDOM PROTISTA PHYLUM - PROTOZOA The name Protozoa (Protos = first, zoon = animal) comes from Goldfuss(1818) who, however used the names simply for the lower groups of zoophyta including protozoans, sponges, coelentrates, rotifers, and bryozoans. It was von  Siebold (1845) who, recognised the unicellular nature of Protozoa, first used and defined the name Protozoa in the present sense. The study of Protozoa is known as Protozoology. Characteristics of Protozoa: These are microscopic and colourless organisms. They are terrestrial or aquatic, free living or parasitic. Body exhibit radial or bilateral, spherical or irregular symmetry. Body is naked consisting of uninucleated or multinucleated protoplasm. Body is bound by a delicate membrane or a firm pellicle, theca or lorica or siliceous shell. Locomotion occurs by pseudopodia or cilia or flagella. They are holozoic or saprozoic (feeding on dead organic matter) or holophytic in nutrition. Digestion is intracellular and reserv...