Structure of muscle A muscle has an origin (less movable), belly and the insertion (highly movable) parts. Muscles are surrounded by a sheet of connective tissue called epimysium (site for fat deposition). From epimysium smaller sheets of connective tissue called perimysium arise and divide muscle into several small bundles. This perimysium contains blood vessels, nerves and muscles spindles. Perimysium […]
Types of muscles In mammal three kinds of muscles tissue are found, these types of muscle are Skeletal muscles, Cardiac muscle and Smooth muscle. Skeletal muscles Cross striated and attached to skeleton, 40% of the total body weight, Voluntary neural control. Cardiac muscle Cross striated in structure, Involuntary in function, Under autonomic nervous system control.
Electron microscopic structures of muscle fibers Myofibril Muscle fibres are made up of several hundred to several thousand of parallely arranged myofibrils having the special function of contraction. Each myofibril posses the contractile proteins myosin (thick) and actin (thin) myofilaments results in regular repetition of dark and light bands in the skeletal and cardiac muscles. Each muscle fibre contains about
Electron microscopic structures of muscle fibers Read More »
Transduction of taste There are primarily five tastes like salty, sour, sweet, bitter, and umami. The salt taste is mainly due to the Na+ ions. So the salty food causes opening of the Na+ channels. The substance namely Amiloride inhibits the receptor channels and diminishes the salt sensation of the receptors. The sour taste is due to the
Gustation in animals Gustation in animals is the process of detecting dissolved chemicals emitted from the ingested food. It is the sense of taste. This is carried out by receptor known as taste buds. There are almost 15,000 taste buds in the porcine oral cavity and throat, while 1 550 in the lizards, but only 24 in chickens.
Olfaction in animals Olfaction in animals is defined as the detection of chemicals that are carried in the air. It is the sense of smell. The vertebrates have greater capacity in distinguishing the variety of odorants (chemicals detected by the olfactory system). Olfactory system Olfactory system comprises of the olfactory receptors, supporting cells, and basal
Auditory pathway The vestibulo cochlear nerve end up in the cochlear nucleus of the medulla. The impulses from here are transmitted to superior olivary nuclei, inferior colliculus and median geniculate body of thalamus. From thalamus it endsup in temporal lobe of cerebral cortex (auditory cortex) Temporal lobe sends efferent to limbic system for behavioural modification
Process of hearing The pinna concentrates the sound waves to the auditory canal which conducts the sound waves to the ear drum. The sound waves strike the ear drum causing it to vibrate. These vibrations are conducted by the ear ossicles to the inner ear through the oval window. The vibrations cause the perilymph to
Auditory apparatus Auditory apparatus The sense of hearing is the process of detecting and interpretation of sound waves. It is done by the organ called as the ears. Ear The ear consists of three parts: The outer ear, middle ear, and inner ear. The outer ear is of the external pinna and the auditory canal.
Accommodation of the eye Accommodation of the eye is the ability of the eye lens to change its focal length by changing its radius of curvature. In near vision contraction of ciliary muscels causes decreased tension to the suspensory ligament and causes bulging of the anterior curvature of the eye. To cause distant vision ciliary
