Comparative study of Heart With answer By Dr. V. S. Kamble Department of Zoology Sangola College, sangola

Comparative study of Heart

1.      The heart is pumping organ operates                                                            Arterial and venous system

2.      In the case of fishes, the heart shows presence of-----  chambers.                    02  

3.      In the case of Amphibia , the heart shows presence of -----chambers              03

4.      In the case of Reptile , the heart shows presence of chambers                        Incomplete 04 chambers

5.      In the case of Aves and Mammals , the heart shows presence of--------- chambers             04

6.      The heart is enclosed in double-walled membrane of called as                 pericardium                       

7.      The sinus venosus is formed by the union of two                                Two precava and one post cava

8.      Cordae tendineae prevents the ventricle from collapse  & expansion of the heart.

9.      In the heart of fish only deoxygenated blood is circulates hence it is called as           Venous heart   

10.  In amphibians purification of the blood is takes place in                                             Lung and skin

11.  Truncus arteriosus shows two parts that are                  proximal pylangium and a distal synangium

12.  In fishes the circulation is                                                                                 Single Circulation

13.  In Mammals  the circulation is                                                                         Double circulation

14.  Through the heart of Fishes only                                        Deoxygenated / Venous blood is circulate 

15.  In reptile .respiration takes place by                                                                Lung only

16.  In amphibian trunchus arteriosus shows presence of characteristic vale called        Spiral valve

17.  In reptiles mixed type of blood is circulating because of the                                Foramen of  Panazzae

18.  18). In birds/mammals the opening of post cava into right chamber of the auricle      Tricuspid valve

is guarded by

19.  The heart of fish is called as                                                                 Branchial heart or Venous heart

20.  In the case of amphibians in water respiration takes place.                      Skin (Cutaneous respiration)

21.  In the case of birds & mammals pacemaker system consist                                 SA node and AV node

22.  Conous arteriosus is present in                                                                                    Fishes

23.  Trunchus arteriosus is present in                                                                                  Amphibian

24.  The blood passes through only once hence circulation is called as                            Single circulation

25.  In the case of vertebrates the left chamber of auricle receives                                   oxygenated blood

26.  In crocodile heart is of                                                                                                 04 Chambers

27. Double circulation occurs in                                                                           Aves and Mammals

respiratory systems in calotes (lizard), columba (pigeon) and oryctolagus (rabbit).

 

respiratory systems in calotes (lizard), columba (pigeon) and oryctolagus (rabbit).

 Comparative anatomy of respiratory systems in calotes (lizard), columba (pigeon) and oryctolagus (rabbit).

Calotes is a poikilothermic terrestrial lizard. It is commonly known as garden lizard.

Columba and oryctolagus are homoiothermic animals.

Columba is commonly known as pigeon adapted for aerial mode of life.

Oryctolagus is herbivorous mammal.

It is commonly called rabbit. All these three animals are grouped under Amniota.

 

Living cells require energy for performing metabolic activities. This energy is provided by the oxidation of food materials present within the cells. During oxidation the oxygen is consumed and releases carbon dioxide and water. Carbon dioxide is harmful to the protoplasm. Hence to keep the oxidation continuously, there is a constant need for the supply of oxygen to the cells and the removal of carbon dioxide from them. Oxygen is obtained from the environment (water or air) and in return carbon dioxide is added to the environment.

The exchange oxygen of the environment with the carbon dioxide of the body is known as 'respiration'.

 In all vertebrates, some organs of the body are specialised for the exchange of gases. These are called 'respiratory organs or breathing organs'. The surface of these organs at which the exchange takes place is called respiratory surface.

LUNGS OF RABBIT

Vertebrate respiratory organs include the gills and the lungs. Both of these organs develop from the pharynx. Lungs arise in the embryo as an endodermal diverticulum from the ventral wall of the pharynx. The diverticulum soon divides into two parts, which form right and left lungs. A windpipe or trachea connects the lungs with the pharynx. Anterior part of the trachea is modified into the larynx. The larynx communicates with the pharynx by a slit like opening the glottis. The laryrnx functions as sound producing organ in tetrapods except in birds. The birds have their sound-producing organ known as 'syrinx'. The trachea bifurcates into two branchi. Each primary branchus further divided inside the lungs as secondary bronchi, tertiary bronchi and bronchides. The bronchides are connected to the alveoli.

 

In vertebrates the blood plays a vital role in respiration. It carries oxygen from the lungs to the cells for oxidation and collect carbon dioxide for removal from the body. There are two phases of respiration. The exchange of gases takes in the lungs is called 'external respiration'. In the tissues the gaseous exchange takes place and it is termed internal respiration. The respiration performed by the lungs is called 'pulmonary respiration'.

   

Calotes (Garden lizard)	Columba (Pigeon)	Oryctolagus (Rabbit)
1. Paired external nostrils are small and oval apertures situated dorsally at the tip of the snout.	1. Paired external nostrils are oblique slits present far above the mouth and lie at the base of the upperbeak.	1. Paired external nostrils are oblique slits lying a little above the mouth.
2. External nostrils are uncovered and are not connected to the mouth.	2. Same as in calotes.	2. External nostrils are partly covered by fleshy tip of the snout and are connected with a cleft in the upper lip.
3. External nostrils possess valves.	3. Valves are absent.	3. Valves are absent.
4. Nasal chambers are small and do not have the conchae.	4. Nasal chambers are small and conchae are present.	4. Nasal chambers are long and have conchae.
5. Nasal chambers remain separate throughout as there are two internal nostrils.	5. Nasal chambers remain separate throughout as these are two internal nostrils.	5. Nasal chambers join posterior as there is a single internal nostril.
6. Paired internal nostrils open into the anterior part of the buccal cavity.	6. Paired internal nostrils open into the posterior part of the buccal cavity.	6. Internal nostril opens into the pharynx.
7. Glottis is without epiglottis.	7. Same as in calotes.	7. Glottis is covered by a cartilagenous plate-epiglottis.
8. Larynx is supported by a pair of arytenoids and a median single cricoids cartilaginous plates.	8. Larynx is supported by the same cartilagenous plates as in calotes. But the cricoid is sub-divided into four pieces procricoids.	8. Larynx is supported by four cartilagenous plates. Median ventro-lateral Thyroid, ring-like lower cricoid and paired arytenoid cartilages on the dorsal side. It is also lined by ciliated epithelium.
9. Laryrnx is a voice-box by possessing paired vocal cards which are functional.	9. Larynx is poorly developed and nonfunctional, ie. The sound is not produced.	9. Larynx possesses a pair of vocal cards and their vibrations produce sound.
10. Larynx has two paired muscles - innermusculus compressor laryngis and outer musculus dilater laryngis. It opens into the trachea.	10. Same as in calotes. Larynx opens into the trachea.	10. Same as in Columba and the larynx opens into the trachea.
11. Trachea is supported by complete cartilaginous rings.	11. Trachea is supported by incomplete bony rings present dorsally.	11. Trachea is long, thin walled tube, supported by incomplete cartilaginous rings present dorsally.
12. Bronchi have complete cartilagenous rings.	12. Median incomplete cartilagenous rings are present in the bronchi.	12. Bronchi have incomplete median and dorsal cartilaginous rings.
13. Bronchides are not formed.	13. Bronchides are formed in a complex manner.	13. Bronchides are formed by repeated branching of bronchi.
14. Syrinx is absent.	14. The sound producing organ Syrinx is present at the bifurcation of the trachea.	14. Syrinx is absent.
15. Lungs have orange colour. These are elongated bodies of fairly large size.	15. Lungs have pinkish colour. These are ovoid organs relatively small in size.	15. Lungs have pinkish colour. These are irregular organs of large size.
16. Lungs are hollow sacs with thin elastic wall. These are having low septa and shallow alveoli on the inner surface.	16. Lungs are compact spongy organs. They are slightly distensible.	16. Lungs are soft, spongy and elastic organs.
17. Lungs are not differentiated into lobes.	17. Same as in calotes.	17. Lungs are divisible into lobes. The right lung has four lobes Anterior azygos, anterior, posterior and posterior azygos. The left is divisible into two lobes-anterior & posterior.
18. Lungs are enclosed by peritoneum.	18. Lungs don't have peritoneum on the dorsal side.	18. The lungs are completely covered by peritoneum. The space between the lungs is called mediastinum where heart is present.
19. Air sacs are absent.	19. Lungs are associated with thin, transparent air sacs. There are nine air sacs. These are, median interclavicle, paired cervical, paired anterior thorasic, paired posterior thorasic and paired abdominal air sacs.	19. Air sacs are absent.
20. The inter costal muscles help during the processes of inspiration and expiration.	20. The inter costal and abdominal muscles help during the processes of inspiration and expiration.	20. The inter costal muscles and peripheral muscles of diaphragm help during the processes of inspiration and expiration.
21. Gaseous exchange occurs through the entire inner surface of the lungs.	21. Gaseous exchange occurs in the blood capillaries present in the lungs. Double respiration takes place since the air is preserved in the air sacs.	21. Gaseous exchange takes place in the alveoli present within the lungs.
22. Some deoxygenated residual air is left over in the lungs. Hence aeration of blood is not very efficient.	22. Residual air is not left over in the lungs.Hence aeration of blood is very efficient.	22. Some deoxygenated residual air is always left over in the lungs. Hence aeration of blood is not so efficient.

 

Integument of vertebrate

 

1.      Scoliodon and Rana are poikilothermic animals. Scoliodon is an aquatic cartilage fish. Rana lives in water and on land-amphibian.

2.      In both the vertebrates the skin (integument) is the outermost covering of the body.

3.      It is multicellular and multilayered structure typically formed of an outer layer of 'epidermis' and an inner layer of 'dermis'.

4.      The integument provides a characteristic form to the body. It also protects the enclosed organs.

5.      The epidermis is derived from the ectoderm and dermis from mesoderm of the embryo.

6.      The epidermis is multilayered and differentiated into stratified epithelium and cornification is not complete.

7.      The cells of stratum corneum are nucleated.

8.      The lowermost layer of the epidermis formed of living columnar cells and is called 'stratum malpighii'or stratlim germinativum.

 

Scoliodon (fish) - skin	Rana (frog) - skin	Calotes skin (reptile integument)	Columba skin (bird integument)	Oryctolagus skin (mammal integument)
1. Skin is rough & tough. It is firmly attached to the underlying muscles.	1. Skin is soft, smooth and loose. It is separated from the underlying muscles by lymph sacs.	1. In Calotes (Reptile) the skin is rough, thick, dry and scaly. Skin is suited to the terrestrial environment which prevents any loss of water.	1. In birds the Skin is thin, loose and dry.	1. In Mammals Skin is thick, elastic and water proof.
2. The skin is divided into epidermis and dermis.	2. Same.	2. Epidermis has a heavily cornified stratum, corneum which produce into hormy epidermal scales.	2. The epidermis is thin and delicate all over the body except on sharks and feet where it is thick and produce epidermal scales.	2. The epidermal cells form into four layers - Stratum corneum, S. lucidum, S. granulo sum  & stratum.
3. The epidermis is composed of many layers of similar epithelial cells. Stratum corneum is absent.	3. The epidermis is distinguished into stratum corneum and stratum malpighii.	3. The exoskeleton of scales is periodical­ly cast off either in fragments or as a sin' gle piece. In turtles & tortoises the epidermal bony plates are formed. In others the scales are modified into shields, scutes, spines etc.	3. The exo Keleton is in the form leathers which are formed from structure corneum & stratum malpighii. The feathers are keratinised.	3. The epidermis also forms Sebaceous and sweat glands. The mu­cous glands are ab­sent. The sweat glands help in excretion and maintain constant body temperature. Sebaceous glands se­crete 'sebum' which lu­bricates the skin and hairs. Hairs are present.
4. Unicellular mucous glands are present in the dermis.	4. Mucous glands or cutaneous glands are multicellular and are present in the dermis.	4. The glands are practically absent. The only glands present are 'scent glands'.	4. The epidermis is devoid of glands except the single "uropygial gland" present at the base of the tail. The oily secre¬tion of the glard is used for preening the leathers.	4. Presence of mammary glands is the charac­teristic of mammals (Rifled sebaceous glands.)
5. Dermis is less vascularised.	5. Dermis is richly vascularised.	5. Dermis is thick having stratum spongiosum & stratum com pactum.	5. Two layers are present in the dermis which is thin. Vascular layer is present in between the two layers.	5. Dermis is very thick. It has intricate system of connective tissue fibres extending in all direc­tions.
6. The skin is protective and sensory in function.	6. Skin is protective, sensory and respiratory (Cutaneous respiration) in function.	6. Stratum spongiosum has numerous chromatophores. They exhibit   wide colour patterns.	6. Chromatophoresare absent. But the pigment is found in the feathers and scales.	6. Chromatophores are absent large dendritic melanophores are present.
7. Placoid scales are present.	7. Scales are absent.	7. Sensory corpuscles are absent.	7. Cutaneous receptors are present in the dermis.	7. Numerous tactile corpuscles are highly developed.
8. Dermis has no layers.	8. Dermis has stratum spongiosum & stratum compactum.	8. Fat cells are not present in the dermis. Femoral glands are present.	8. Fat cells are present in the dermis.	8. Subcutaneous layer is formed of adipose tissue (Fat cells).
9. In the dermis chromatophore and iridocytes are present.	9. Chromatophores are found in the upper part of dermis. These help in changing the colour of integument.	9. Distal ends of the digits have nails or claws which formed from the homy epidermis. These grow  parallel to the surface of skin and formed of a dorsal plate 'unguis' (nailplate) and a ventral plate sub unguis (sole plate).	9. Similar claws are with unguis in the form of a long plate of keratin sharply curved and subunguis lies between its two edges.	9. Nails & hoofs are found. At the base of the nail, the epidermis is invaginated to form nailgroove and its part covering the nail root-eponychium.
10. In some deep-sea fishes light emiting photophores are present.	10. In some frogs (Bufo) poison glands are present near the tympanum.	10. Horny teeth are present which are acrodont or pleurodont Similar claws are with unguis in the form of a long plate of keratin.	10. Beaks are formed of enlarged epidermal scales which form hard keratinized covering over the jaw bones.	10. Hairs are keratin derivatives and exclusively present in mammals. These are strictly epidermal structures developed from stratum malp

 

 

Integument of Amniots

1.      Calotes is a terrestrial Reptile (lizard). Columba is flying bird. Oryctolagus is a herbivorous mammal. All these animals are grouped under Amniota and columba & oryctolagus are warm blooded animals. The integument forms the outermost covering of the body in all these animals. It is multilayered in structure and is distinguished into epidermis and dermis.

2.      The epidermis consists of several rows of flattened stratified epithelial cells stratum corneum.

3.      Below this layer stratum Malpighi is formed with living columnar cells.

4.      The dermis is formed of connective tissue traversed with collagen and elastin fibres, muscles, nerves, blood capillaries and lymph vessels etc.

5.      It possesses an upper stratum spongiosum and a lower stratum compactum layers.

6.      The epidermis and dermis are formed from ectoderm & mesoderm layers.