Frog- Rana tigrina (Amphibian) A frog is an amphibian, living both on land and water. Amphibians are the first group of chordates that lived outside water. These are coldblooded vertebrates tetrapods. Classification of Rana tigrina (Frog): Phylum – Chordata Subphylum – Gnathostomata Superclass- Tetrapoda Class- Amphibia Order- Anura Genus- Rana Read more…
Parental Care in Fishes We can define parental care as an association between parents and the offspring through which the chance of survival of young ones gets increased or any behaviour performed by parents that appears likely to improve the survival and reproduction of the young. In the case of Read more…
Scales in Fishes The term Scale is derived from the Old French “escale” meaning a shell pod or husk. Fish Scale Fish scales are part of the Fish’s integumentary system, and these are originated from the Mesoderm layer of the dermis. A fish scale can be defined as the rigid Read more…
Migration in Fishes Many fishes migrate on a regular basis, on a time scale ranging from daily to annually or longer. It may be of short distance over a few meters to thousands of kilometers. Reason for Migration in Fishes: Fishes usually migrate to feed, to reproduce, or in some Read more…
Scoliodon – Dogfish, Classification, and Characteristics The Scoliodons commonly called dogfishes are the requiem sharks in the family Carcharchinidae. These are found mainly in the Indo-West Pacific oceans from the western coasts of Africa to the south of Japan. Scientific classification of Scoliodon: Systemic Position of Scoliodon Phylum Chordate Subphylum Read more…
Herdmania- Sea Squirts Systematic position of Herdmania Kingdom- Animalia Phylum- Chordata Sub Phylum – Urochordata, Tunicata Class- Acidiacea Order- Pleurogona Suborder- Stolidobranchia Family – Pyuridae Genus- Herdmania Habit and Habitat: Herdmania is a sedentary filter-feeding tunicate found in marine habitats. The animal often occurs in a gregarious form. These are Read more…
Balanoglossus It is a marine water-dwelling acorn worm (Enteropneusta). Blanoglossus cannot survive in freshwater. It belongs to hemichordates. it is an “evolutionary link” between invertebrates and vertebrates. Discovered by J.F. Eschscholtz in 1825 in Mashail Island. He described it as a worm-like holothurian. Kowalewski (1865) discovered the gill – slits Read more…
Subphylum – Urochordata (Tunicates) Subphylum – Urochordata: Position of Urochordates- Lamarck placed Tunicata in between radiate and Vermes in his system of classification. Later they were kept in Mollusca. Kowalevsky kept them in chordates in 1866. The Urochordates are also known as tunicates. These are commonly known as “sea squirts”. Read more…
Amphioxus (Lancelet) The Amphioxus also known as lancelet, Consisting of 30 to 35 species of “fish-like” chordates. Branchiostoma is one of the few living genera of lancelets. It is the type genus of the family Branchiostomidae. The lancelets are believed to be related to Pikaia (530-million-year-old) fossils. The first representative Read more…
Blood Groups: Types of Blood Grouping The blood is classified on the basis of the presence and absence of antibodies and inherited antigenic substances on the surface of RBCs (red blood cells). The antigens may be proteins, carbohydrates, glycoproteins, or glycolipids, depending on the blood group system. Blood types are Read more…