Write short notes on the following:

(a) Neural coordination

(b) Forebrain

(c) Midbrain

(d) Hindbrain

(e) Retina

(f) Ear ossicles

(g) Cochlea

(h) Organ of Corti

(i) Synapse

Asked by Pragya Singh | 1 year ago |  62

1 Answer

Solution :-

(a) A neural system facilitates the interaction and complementing of the activities of two or more organs. Interconnected and interdependent are all of the body's physiological functions. Coordinating and integrating all the organ's functions, the brain and endocrine system work together. Brain systems provide fast coordination by organising a network of interconnected points. Hormones enable chemical integration by the endocrine system. 

(b) Among the three parts of the cortex are cerebrum, thalamus, and hypothalamus. The brain's main structure is the cerebrum. Left and right cerebral hemispheres are separated by a fissure in the cerebrum. Connecting the hemispheres is the corpus callosum. Cells that cover the cerebral hemisphere make up the cerebral cortex, which is a layer of pronounced folds. It is referred to as grey matter because of its greyish coloration. Several portions of the cerebral cortex have no obvious sensory or motor function. A variety of complex activities are performed by association areas, including intercessory associations, memory, and communication. In the cerebral hemisphere-interior section, the fibers of the tract are protected by the myelin sheath. White matter is named as a result of their impenetrable appearance. Intercessory associations, memory, and communication are all tasks that the association areas are accountable for. The myelin sheath, which makes up the interior section of the cerebral hemisphere, protects the tract fibres. They give the layer an impenetrable white appearance, thus the name "white matter."

→ Thalamus: There is a region within the cerebrum wrapped around the middle of the forebrain named the Thalamus. Sensory and motor signalling are
coordinated at this centre.
→ Hypothalamus: In the hypothalamus there are numerous centres that regulate body temperature, urges for eating, and thirst. In addition to controlling growth and sexual behaviour, it is connected with the pituitary gland.

 

(c) Midbrain :-The midbrain: From the forebrain to the hindbrain, the midbrain lies between the thalamus and the hypothalamus. This section of the brain passes through a canal known as the cerebral aqueduct.
 

(d) Hindbrain:-In the hindbrain, you will find pons, cerebellum, and medulla. There are many neurons in the cerebellum, so its surface is very convoluted in order to accommodate those extra neurons. In the brain, the medulla and spinal cord are connected. Medulla is home to centers that regulate respiratory functions, cardiovascular reflexes, and gastric secretions.

(e) Retina:- Retina, also known as the photoreceptor, is a layer of neural cells located at the back of the eye. It includes ganglion cells, bipolar cells and astrocytes. They act as photoreceptors. Rods and cones make up photoreceptor cells. A cone is a sensory organ that is responsible for the perception of daylight and colour whereas the rods are responsible for twilight vision. Images of objects are formed on the retina by the light entering through the cornea and the lens.

(f) Ear ossicles :-Malleus, incus, and stapes are three ossicles located in the middle ear, which are connected one to another through a chainlike arrangement. Among the three components of the ear, malleus is connected to the tympanic membrane, incus is attached to the stapes, and stapes is attached to the cochlea's oval window. By transmitting sound waves effectively into the inner ear, ear ossicles increase hearing efficiency.
 

(g) Cochlea :-The cochlea is the coiled section of the labyrinth. There is an upper and a lower scala tympani in the cochlea, composed of reissner's and basilar
membranes. Scala media, which fills the cochlea, contains endolymph. A rectangular window open to the middle ear accompanies the oval window at the base of the cochlea, and a round window opens to it at the base of the cochlea.

 

(h) Organ of Corti :-In the organ of corti, hair cells function as auditory receptors located on the basilar membrane. On the inside surface of the Corti organ, hair cells are arranged in rows.


(i) Synapse :-The synaptic cleft is a gap between postsynaptic cells and presynaptic cells that divides the synaptic membranes. Synapses are of two different types:
chemical and electrical.

Answered by Abhisek | 1 year ago

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