Plankton are a microscopic aquatic organisms that incapable of swimming against a current. Plankton are mainly two types such as Phytoplankton that means plant like plankton (i.e. diatoms, cyanobacteria, dinoflagellates and coccolithophores) and Zooplankton that means animal like plankton (i.e.
Osmoregulation
Osmoregulation is a physiological process for regulating the water balance of an organism and maintaining the proper osmotic concentration of the body fluids. Osmoregulation means the control of the water content and the concentration of salts in the body of
Neurone
Neurone is a nerve cell body with its axons and dendrites, the fundamental unite of nervous system. Also spelled Neuron and called Nerve cell. It is the developmental, structural and functional unit of nervous system and compiled of nerve cell
Mesoderm
Mesoderm is one of three germ layers of triploblastic animal embryo, lying between the ectoderm and endoderm. Gr. mesos means middle and derma means skin The muscles, bones, cartilages, fibrous connective tissues, dermis, gonads, kidney, urinary ducts, cortex, spleen and
Larva
Larva is the developmental stage between embryo and adult. Naturally it is started after hatching and continued before adult by the process of metamorphosis. The morphological characteristics of a larva are varying from embryo and adult. Mostly free living and
Kidney
The main excretory organ of vertebrates consists of large number of malpighian bodies each consisting of a glomerulus (minute coiled blood vessel, invested by a funnel-shaped capsule) or an organ of like function in invertebrates. In invertebrates, kidney means an
Jugular fin
In some fishes (Blennies: fishes under Blennioidei family), pelvic fins are situated far forwards in the anterior region of the pectoral fins. This type of pelvic fins is called as jugular fins. Jugular means of, relating to, or located in
Integument
Integument is the natural outer covering of an animal body. Such as- Skin, Shell, Carapace, Cuticle etc. Skin founds in fishes and other vertebrates as an integument and consists of mainly epidermis and dermis. Shell, carapace and cuticle are present
Heart
A muscular organ that pumps blood round the circulatory system in higher animal. It is an enlarged muscular part of blood vessel that contains at least two valves to prevent back flow of blood. It is derived into two or
Gill
Gill is a respiratory organ by which the aquatic animal can obtain dissolved Oxygen (O2) from surrounding water and release Carbon dioxide (CO2) in aquatic environment. Gills are the most efficient mechanisms for aquatic respiration. Four pairs of internal fills
Exotic fish
Fishes which are not native and introduced to an area outside of their origin. More then 79 varieties of ornamental and 12 species of cultured exotic fishes are recorded in Bangladesh. Most common exotic ornamental fishes of Bangladesh are Sword-tails,
Dorsal
Generally dorsal means near the back or upper part of an animal. In fishes, dorsal part always stays in the opposite side of bottom/floor of water-bodies during locomotion. It is an opposite end of belly, abdomen or ventral. In most
Fish
Fish is a group of cold-blooded (ectothermic) aquatic vertebrates with gills for aquatic breathing and paired and/or unpaired fins for swimming. Rui, Catla, Mrigal, Hilsa is very common fish in Bangladesh. Different types of shape are found in fishes. Such