Deglutition (Swallowing) in animals Deglutition (Swallowing) in animals is the act of passage of food from the mouth to the stomach through pharynx and esophagus. It starts, as a voluntary act then becomes an involuntary reflex during its execution. The afferent nerves originate from receptors located in the posterior part of the mouth and pharynx. […]
Mastication in animals Extensive chewing of the feed causes mechanical reduction in the size of the food, this is known as mastication in animals. The finely divided food particles provide greater surface area for enzymatic action and proper mixing with saliva for easy swallowing. This act is achieved by deduction and occlusion of both the
Basic Physiology of Digestion of animals Digestion is the process of breakdown of complex food into simpler form by the activities of the alimentary tract and glandular secretions for absorption of nutrients and the rejection of their residues. Food Food is a complex mixture of substances like carbohydrates proteins, fats, vitamins, inorganic salts and water to meet the nutritive requirements
Characteristics of different types of muscles Property Skeletal Smooth Cardiac Cell shape, size and interactions and cell organelles Cylindrical 10 – 100 µm diameters 2-3 cm long, no electrical coupling (cell to cell conduction), no branching, prominent T- tubules, multiple nuclei, varying degree mitochondria present, triad is prominent. Elongated fusiform 1 – 12 µm dai.,15
Membrane potential in cardiac muscle Resting membrane potential in cardiac muscle The resting membrane potential in cardiac muscle is – 90 mV, but has long action potential (250msec). Cardiac muscle = – 85 to – 95 mV Conduction system = – 90 to -100 mV Ventricle muscle = -100 to -105 mV S.A. node =
Physiology of Cardiac muscle Involuntary, single centrally located nucleus, numerous mitochondria. The T-tubular of mammalian cardiac muscles are larger (esp. in Ventricles) than those of skeletal muscles and are located at the Z lines rather than at the A – I band junction as in skeletal muscles fibers. While the groups of skeletal muscle fibers
Action potential in smooth muscle Slow wave rhythm Some smooth muscles are self excitatory i.e. elicite AP with out an extrinsic stimuli; due to waxing and waning of pumping of Na+ outward – if rapid sudden decrease in electronegativity, if slow gradual decrease in electronegativity and once reaches – 35 mv causing action potential. ie., most of
Smooth muscle tissue Contains action and myosin filaments with are not orderly arranged. So there no striations present in smooth muscle tissue. Two types of smooth muscles- 1. Visceral smooth muscles About 99% of the smooth muscles are of the unitary type. The fibers are tightly bound together top form continuous network called ‘syncytium’ and wrap
Work done by the muscle Work done (W) = (Hxl)/L here- L – Length bet fulcrum and the tip of the lever L – Length bet fulcrum and the weight load H – Observed HT on contraction The chemical energy liberated during contraction is party converted into mechanical energy with fibers indicated fraction of total
