Skip to main content

Batrachospermum :Origin ,strucutre ,Thallus organisation and reproduction

By
                                              Batrachospermum Occurrence:-   (1) Batrachospermum is fresh water alga.    (2) It is found in clear, cool, and running streams.   (3) Deepwater plants are dark violet or reddish in color. But the shallow-water species are olive green.   (4) The intensity of light changes the color of pigments.   (5) The thallus is attached to the substratum. Vegetative structure  (1) The thallus of an adult plant is soft, thick, filamentous.  (2) It is freely branched and gelatinous.   (3) The central axis is made up of a single row of large cells. Whorls of branches of limited growth        are developed on this axis.  (4) These branches are filamentous and dichotomously arranged.  (5) The main axis is corticated. It consists of a row of elongated cylindrical cells....
Post a Comment

Biological Classification of Echinodermata and Mollusca

By


                                                         Kingdom Animalia
Phylum Echinodermata:-

Echinus (Spines) dermal(Skin or layer ), means spines bearing animals.
Biological Classification of Echinodermata and Mollusca
Echinodermata


(1)   These are exclusively marine.
(2)   Organ level of organization.
(3)    Radial symmetry with the Bilateral larval stage.
(4)    Body without segmented.
(5)    Coelom present.
(6)   Triploblastic and Schizocoelom.
(7)   Presence of Tube feet.
(8)   Water The vascular system is present
(9)   The shape of the body is star-shaped, flat and elongated.
(10)  The function of Water Vascular System is  (Hint:- LCR circuit)  
                                         Locomotion, Circulation, and Respiration.

(11)     Blood has no Pigment or blood is colorless.
(12)     Digestive of the system is Complete.
(13)     Sexes are Monoceious or may be Diecious.
(14)     Development is indirect with the formation of the larval stage
(15)     Sea cucumber larva is “auricularia “.

This Phylum is divided into 5 classes:-

Asteroidea:-

(1)  The body is flattened star-shaped with five arms
      (2) They possess tube feet with a sucker
      (3) Presence of calcareous plates and movable spines.
      (4) Respiratory organ: papulae
        Examples: Asterias (Starfish), Astropecten, Zoraster, Oleaster

 Ophiuroidea:-
      (1)  The body is flat with pentamerous disc
      (2)   They possess a long arm which is sharply demarcated from the central disc.
      (3)    They possess tube feet without sucker
      (4)  Anus and intestine are absent
      (5)    Respiratory organ: Bursae
         Examples: Ophiderma, ophiothrix, Astrophyton, Amphuria, etc

 Echinoidea:-

       (1) The body is disc-like hemispherical
         (2)They are devoid of arms or free-rays.
         (3)They possess tube feet with a sucker
.        (4) They possess compact skeleton and movable spines
.          Examples: Echinus (Sea urchin), Cidaris, Arbacia, Echinocardium. Diadema

Holothuroidea:-

  (1) The body is elongated in the oral-aboral axis and it is like cucumber.
  (2) They have no arms, spines, and pedicellariae.
   (3) The tube feet are sucking type which is modified into tentacles and form a circle  
around the mouth.
   (4)  Respiratory organ: cloacal respiratory tree
    Examples: Cucumaria (Sea cucumber), Holothuria, Mesothuria, etc

 Crinoidea:-
     (1)Body is star-shaped
     (2)Some of the forms were extinct and living forms.
     (3)Arms bifurcated, with two pinnules.
     (4)They have tube feet without suckers
        Examples: Neometra, Antedon, Rhizocrinus, etc


Phylum Mollusca:- 

                      Soft-bodied Organism With a covering of cavity is called Molluscan
Biological Classification of Echinodermata and Mollusca
Mollusca


   (1)   Infolded A skin forms hard covering on the surface of the Mental cavity.

   (2)  Schizocoelom type of Coelom.

   (3)  Organ Level of organization.

   (4)  Bilateral symmetry.

     (5)  Closed circulatory system.

     (6)  Respiration is by Gills (Ctnidia) Present in Mental cavity.

     (7)  Excretion by a Pair of metanephridia.

     (8)  The heart consists of One Auricle and one ventricle.

     (9)  Nervous the system consists of Three pair of Ganglia,(cerebral, visceral, and pedal).

(10) Reproduction by Fusion of gametes.

     (11) Development may be direct or indirect by Trochophore larva.

      (12) Fertilization external or Internal.

Mainly this Phyla is classified into 3 classes, Total 6 classes but we study only 3 classes.

             

(1) Gastropoda
(2) Pelecypoda
(3) Cephalopoda

 (1) Pelecypoda:-

               (1)  Habitat: mostly marine
               (2) They burrow in mud and sand.
               (3)  Symmetry: bilateral and the body is laterally compressed.
                (4)  No distinct head
                  Examples: Mussels, Unio, Mytilus

     (2) Gastropoda:-

                  (1)Habitat: These are either aquatic or terrestrial
                    (2)  They possess a spiral shell.
                    (3) The foot is large and flat.
                    (4) The Head is well developed with tentacles and eyes.
                    Examples: Hilex (Snail), Limax (Slug), Pila (Apple snail).
        (3)   Cephalopoda
       (1)  Habitat: mostly marine.
       (2) They are adapted for swimming.
                    (3)The foot is modified into eight to ten long tentacles in the head region.
                    (4)The shell is either external, internal, or absent.
                    Examples: Octopus, Loligo, Sepia, spirula, Nau










Labels:

Comments

Post a Comment

Thanks

Popular posts from this blog

Ectocarpus -Characterstics ,Thallus and Reproduction

By
                                   Ectocarpus                                               Superphylum:-Heterokonta                                               Class:-Phaeophyceae                                       ...
Post a Comment
Read more

Pinus -External Morphology,Internal Structure and Reproduction

By
                             Pinus External morphology :- Root :-     The tree has a well developed tap root system . When the plant is growing on a shallow soil in the hills ,the lateral roots spread very wide to fix the plant firmly into the plant firmly into the   soil. Pinus Morphology Roots make association with fungi in the soil called mycorrhizae.it is kind of symbiotic association where the fungud does not affect the plant root bt provide soil nitrogen and phosphate and other minerals from root to the root . Stem :-   Stem is woodly and branched .the lower unbranched part of the stem is called Trunk  . (1)    Branch of limited growth (2)    Branch of unlimited growth . The branch is excurrent where the terminal bud or main stem shows more ...
Post a Comment
Read more

Structure and Function of Endoplasmic Reticulum

By
Endoplasmic reticulum  :-  The electron microscopic membrane bound system present in the cytoplasm is called endoplasmic reticulum It is reported by porter in 1945,it connects the nucleus to the one end and other end is connected by cell membrane. It has two parts :- (1)Smooth endoplamic reticulum (2) Rough endoplamic reticulum. ER Contains Cisternae,tubules abd vesicles Endoplasmic Reticulum Cisternae  :- These are long, flat and un-branched plates or lamellae arranged in parallel rows. (b)  Vesicles :- They are usually round or ovoid sacs. They often occur isolated in the cytoplasm. (c)  Tubules :- They are irregularly branched tube-like structures having a diameter of 50-100n. These are surrounded by this unit membrane of 50-60 thickness and their lumen is filled with the secretary products of the cell. Smooth endoplasmic  reticulum  :- The SER is smoothly surface ER but RER...
1 comment
Read more