Sensory Receptors and Organs
Receptors gather outside information. Exterorreceptores are sensory structures that make up the organs.
The eye is composed of 3 layers: sclera, choroid, and retina. The eyeball contains aqueous liquid and vitreous. The cornea bends light, and the lens focuses images. The retina receives inverted pictures, and fotorreceptors convert images into impulses.
The ear has 3 parts: external ear, middle ear, and inner ear. It is responsible for hearing and balance.
The skin has two layers: epidermis and dermis. It contains various receptors for pressure, cold, heat, and contact.
The nose contains mucosa and pituitary, which are responsible for olfactory receptors and heating the air.
There are 4 flavors on the surface of the tongue, and the sense of taste is related to smell.
Various diseases affect the eyes, ears, and skin, such as glaucoma, hyperopia, myopia, astigmatism, otitis, and rhinitis.
The stimulus-receptor-effector system is controlled by the nervous system. Neurons transmit nerve impulses and are composed of the cell body and axon. The central nervous system (CNS) is responsible for monitoring the body and its activities. The sensory nervous system (SNP) transmits nerve impulses from receptors to the CNS and to the effectors. The brain and spinal cord are part of the SNP, and they regulate involuntary functions.