Honours / Core Course (CC)
COMPARATIVE ANATOMY OF VERTEBRATES
Unit 1: Integumentary System
Mechanism of Respiration, Respiratory volumes and capacities, transport of Oxygen and Carbon dioxide in blood, Dissociation curves and the factors influencing it, respiratory pigments; Carbon monoxide poisoning
Q.What is pterylae?
Contour feathers are evenly distributed over the bodies of several kinds of birds (probably primitive condition), but usually are restricted to feather tract, called pterylae. The feathers spread from the pterylae to cover the intervening areas. The conformation of pterylae is of use to systematists.
Unit 2: Digestive System
Comparative anatomy of stomach; dentition in mammals
Q.Distinguish between brachyodont and hypsodont teeth.
Unit 3: Respiratory System
Respiratory organs in fish, birds and mammals
Q.What do you mean by mammalian ventilation?
Mammalian ventilation is bidirectional and involves the rib cage and diaphragm. Upon inhalation, the external intercostal muscles contract to rotate the adjacent ribs and medial sternum forward. Because the ribs are bowed in shape, this rotation includes an outward as well as a forward swing of each arched rib. The result is to expand the space that the rib cage encloses around the lungs. Contraction of the dome-shaped diaphragm causes it to flatten, further enlarging the thoracic cavity.
Unit 4: Circulatory System
General plan of circulation, Comparative account of heart and aortic arches
Q.Demonstrate cardiac shunt in crocodile.
The pattern of cardiac blood flow changes because of a cardiac shunt.
Changes /Adaptation/Modification in the process of cardiac circulation is presented in a flow chart fashion as follows—
Q.Give a comparative account between aortic arch in Anura and Urodale.
Unit 5: Urinogenital System
Succession of kidney in different vertebrate groups; evolution of urino-genital ducts
Q.State the functional significance of glomeruli and tubules.
Functional significance of glomerulus:
1.Because of elevated blood pressure within the glomerulus resulting partly from the smaller size of the different glomerular arteriole, water, certain salts, glucose and other solutes in the blood plasma are filtered into the space between the outer and inner wall of bowman's capsule.
2.Some constituent of the glomerular filtrate may not be expendables and those are selectively reabsorbed during passage through specific segments of the tubule. As a result the composition of the filtrate becomes altered in the passage.
3.All the glucose for example is ordinarily reabsorbed. It is the sole immediately available circulating source of energy it is not readily acquired and it is not ordinarily in excess in the bloodstream because once acquired is quickly stored in the liver, water and certain salts may or may not be in excess depending on the environment.
4.When in excess water is allowed to pass through the length of the tubules and to enter the kidney ducts without having been reabsorbed. Under conditions that tend to lead to dehydration water is reabsorbed from segments of the tubule. Certain salts also are selectively reabsorbed when appropriate.
5.Tubular secretion removed from the circulation useless or harmful substances that were not removed by filtration. Among these are for instance wastes from protein breakdown (nitrogen is wastes) in tetrapods. (Nitrogenous wastes, Sodium ion and chloride ion in most fishes are eliminated by external means)... (For further information follow contact section)
Unit 6: Nervous system and sense organs
Comparative account of brain in vertebrates; cranial nerves; olfactory and auditory receptors in Vertebrates
Q.Give characteristic features of amphibian fore brain.
i)Similar to that of primitive shark and less complex that the reptile.
ii)Primitive pallium and globus pallidus- still prominent.
iii)consists of dorsal, lateral and medial part.
iv)Amygdala- another region of pallium, primarily concerned with receiving accessory olfactory informaqtions from the vomeronasal organ.
Unit 7: Skeletal system
Overview of axial and appendicular skeleton – limbs, girdles of pigeon; jaw suspension in
Q. What do you mean by amphistylic jaw suspension?
Here, the posterior part of the upper jaw orpalatoquadrate is directly articulated to the chondrocranium and in addition, the hyomandibular serves to attach the jaws to otic region of chondrocranium.
This type of jaw suspension is found in primitive sharks like Hexanchus.