-
THE EVOLUTION OF THE HEART
• Heartis a muscular organ .
As per evolutionary point of view the chamber of heart are,
1.SINGLE CHAMBER HEART
• It is found in primitive chordates like amphioxus.
• It is not a true heart.

2. TWO CHAMBER HEART
• It is found in pises.
• It is true heart chamber.
• 2heart chamber
                 a. Atrium- receving chmber
                 b. Ventricle-pumping chamber






• 2 chanber animals also contains gills for respiration.
• Heart of fish receive only deoxygenated blood.
• This type heart is calledbranchialheart or venus heart.
• It is a single circulation path or haert.

Sinus                                 atrium                    ventricle
venosus                                                               
                                     
                                                                        conus arteriosus 
deoxyganated
blood
                           oxygenated                                                 
      organ                                         gills              aorta
                                blood
3. THREE CHAMBER HEART
• 3 Chamber heart is found in amphibius and reptile.
• 3chamberheart,
              a. Auricles- divided 2 chamber
                   i. Right auricle
                   ii. Left auricle
              b. Ventricle

• Respiration for lungs.
• It is a dubble circulation path.
• This type of heart pumps mixed blood is known as atreovenius heart.

4. FOUR CHAMBER HAERT
4 Chamber heart found in birds and mammals.         
                             Human heart
• The ventricle divided 2 chamber , left and right ventricle.
• In birds ventricle is not purely divided.
• It is dubble circulation path.

                           

                                                                       

Comments

Post a Comment

Popular posts from this blog

Excretion in annelida long question for +3 zoology students

-
Image
EXCRETION    IN ANNILIDA - Excretion is defined as the separetion elimation of nitrogenus west from body to out side. - The organ involve in excretion called as ecretory organ. - In annelida exretion is brought about by these following organ. NEPHRIDIA - These are coild tubules arrenged segmentally drive from ectoderm and projected in the nephridia named as 1. proto-nephridia 2. meta-nrphridia A. PROTONEPHRIDIA - These are primitive type of nephridia open to exterior by an opening called nephridiapore. - Internaly it   blindly open towords coelom and are branched. - Each branch ends in a tubular cell ,   called solencytes. - It is a cavity surrounded by cytoplasm mass. - Flagellum arises from the mass of cytoplasm. - It is found in alcepa. B. METANEPHRIDIA - It has two opening ,one end is open to the coelom by funnel like structure called nephrostome. - And orther end open to anterior by nephridiapore,found in nereis. - Nephridium colid tube
Read more

Metamerism in annelida in +3 student zoology paper

-
Image
·    Prof.- Dr ramakant pradhan  best of luck for your exam , you study and ask u doubt or other wise dout in other long question in biology ask me in comment box .ok  student by .  METAMERISM IN ANNELIDA   -     In some animals body is divided into a series of compoctment one behied the other. -    These componets are called segment. -        The inner arrengment of segment is called metamerism . CHARECTERSTICS OF METAMERISM -        In metamerism each segment is the mirror image of other segment. -       Each segment contain nepharidia , blood vessels ,reprodactive organ ,nerve and muscle. -       The segment mark in coporation with all orther segment. TYPES OF METAMERISM . A. True metamerism -        The segment of body is based on segmentation mesoderm. -       It is found is all annelida charecter and arthropods -       New segments are found at the posterior and old segment occours at anterior.   B. Pseudometamerism -       
Read more

Structure of Peripatus and affinity long question for +3 zoology students

-
Image
STRUCTURE   OF PERIPATUS   AND   AFFINITY - Peripatus is a soft bodied worm like , bilaterally symetrical animal. - It shows tracheal mode of respiration. - It is grouped in phylum arthropoda and class onychophora. - Class onychophora inclodes primitive (old) worm like arthropods. - Peripatus connecting like bewteen arhropoda and annelids. - Peripatus seen in neotropical regions like west indies, america, congo and australia etc. - It is the terrestrial animal. - It lives under stones and back ( tree outer layer) of tree and in shady place. - It is nocturnal in habit. ( night standing animal) - During day time it remains in the dark place. - In night time it come out and collect food. - In feeds on small insects , worms etc.   EXTERNAL CHARECTER -It is a soft bodies , worm like animal. - It grows up to 1 to 2 inc length. - The soft body shows deep black colour on the dorsal   side. - The light red colour on the ventral side. -The skin is soft and
Read more