Points On Zoology

SYSTEMATIC POSITION Phylum- Protozoa Subphylum- Sacromastigophora Superclass- Mastigophora Class- Zoomastigophora Order- Kinetoplastida Genus-  Trypanosoma Species-  gambiense INTRODUCTION Trypanosoma is a haemoflagellate digenic  parasite found in the blood of amphibians, reptiles, birds and mammals. 3 species of   Trypanosomes   are found pathogenic and are present in human blood which causes a deadly disease known as African sleeping sickness. The three species are as follows: Trypanosoma gambiense Trypanosoma rodesiense Trypanosoma cruzi Trypanosoma gambiense is an endoparasite. Being digenic, primary host  is Man and secondary host is Tse-tse  fly. HABITAT It occurs in  the blood of man and later on enters the cerebrospinal fluid of the central nervous system.  It is generally confined to  man of central and western Africa and causes African sleeping sickness. DIFFERENT STAGES Morphologically, Trypanosoma occurs in the fol

Plasmodium is a malaria fever parasite, which is a sporozoa i.e., it comes under sub-phylum sporozoa. Generally all sporozoans are parasites. Plasmodium is an endoparasite. They do not have any locomotory organelles. Movement takes place through blood current. They do not have any contractile vacuoles. So, there is no need of phagocytic mode of nutrition. Plasmodium is a digenetic parasite i.e., it needs two host to complete its life cycle. Biologically, the primary host is man and the secondary host is female Anopheles mosquito. There are mainly four species of Plasmodium which causes malaria: Plasmodium vivax      Plasmodium ovale                                                                                      Plasmodium falciparum                                                                                                                Plasmodium malariae Plasmodium vivax causes Benign tertian malaria. Here the peroxism period is about 48 hours and

Phylum Protozoa is classified into 4 distinct sub-phyla on the basis of type of locomotory organelles found in them. The 4 sub-phyla of phylum Protozoa are as follows: Sarcomastigophora Sporozoa Cnidospora Ciliophora 1.  SARCOMASTIGOPHORA Locomotory organelles may be Pseudopodia or Flagella. Nucleus is monomorphic. Asexual reproduction is by binary or multiple fission. Sexual reproduction occurs by fusion of gametes. ​ Sub-phylum Sarcomastigophora is further divided into 3 Super classes i.e.,Mastigophora, Opalinata, Sarcodina (a) MASTIGOPHORA (SUPER CLASS) Flagella are present as locomotory organelles, so they are also called Flagellata. Flagella also acts as food capturing organ. Body is covered by a layer of very thin cuticle or pellicle. Nutrition is holozoic, holophytic or saprozoic. Asexual reproduction by longitudinal fission. ​ Super class Mastigophora has further 2 classes                                      i.e

Proto=Primitive/First/early; Zoon=Animals Earlier protozoans were included under animal kingdom, but now a days they are included in kingdom protista. This is because, protozoa are unicellular eukaryotes. They live in wide varieties of moist habitats such as fresh water, marine environment and may be in moist soil. They may be parasitic or commensal, symbiotic or free living, sessile or motile and mostly solitary and some are colonial. Protoplasmic grade of body organization is seen. Germ layers are absent. Body is naked or covered by pellicle or may be covered by an exoskeleton made up of shell/test/cyst/theca. Almost all types of symmetry are found, i.e-bilateral, radial, spherical and may be no symmetry (asymmetry). Locomotory organelles may be finger like pseudopodia, hair like cilia or whip like flagella. Some species do not have any locomotory organelles (eg., Sporozoans). Division of labour is restricted to organelles. Dimorphic nuclei are found. Nutrition m

Kingdom Animalia or the Animal Kingdom is broadly classified into two groups, i.e., Non-chordates and Chordates. Chordates are the animals those who exhibit a notochord at some stage of their life. Similarly, Non-chordates are the animals those don’t possess notochord at any stage of their life. Notochord (Gr., noton=back,  L., chorda=cord) is a cartilagenous string or rod like stucture present along the back of  chordates, at some stage of their life or throughout the life. Sub-kingdom Non-chordata is further classified into 9 phyla, namely: Porifera Coelenterata or Cnidaria Platyhelminthes Nemathelminthes Annelida Arthropoda Mollusca Echinodermata Hemichordata       Earlier, Phylum Protozoa​ was also included under Animal kingdom, but since, they are microscopic unicellular organisms, now a days they are studied under the phylum Protista.