Anatomia układów zmysłów | Sensory Systems Anatomy

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oka”, “Refractive power”: “Moc refrakcyjna”, “Ciliary muscles”: “Mięśnie rzęskowe”, “Accommodation”: “Akomodacja”, “Lens capsule”: “Torebka soczewki”, “Lens cortex”: “Kora soczewki”, “Lens nucleus”: “Jądro soczewki”, “Sclera”: “Twardówka”, “Choroid”: “Naczyniówka”, “Photoreceptor cells”: “Komórki fotoreceptorowe”, “Rods”: “Pręciki”, “Cones”: “Czopki”, “Photopic vision”: “Widzenie fotopowe”, “Scotopic vision”: “Widzenie skotopowe”, “Macula”: “Plamka żółta”, “Fovea”: “Dołek środkowy siatkówki”, “S-cones”: “Czopki S”, “M-cones”: “Czopki M”, “L-cones”: “Czopki L”, “Bipolar cells”: “Komórki dwubiegunowe”, “Ganglion cells”: “Komórki zwojowe”, “Optic nerve”: “Nerw wzrokowy”, “Ophthalmic artery”: “Tętnica oczna”, “Central retinal artery”: “Tętnica środkowa siatkówki”, “Central retinal vein”: “Żyła środkowa siatkówki”, “Vortex veins”: “Żyły wirowate”, “Oculomotor nerve”: “Nerw okoruchowy”, “Trochlear nerve”: “Nerw bloczkowy”, “Abducens nerve”: “Nerw odwodzący”, “Auricle”: “Małżowina uszna”, “External auditory canal”: “Przewód słuchowy zewnętrzny”, “Tympanic membrane”: “Błona bębenkowa”, “Eustachian tube”: “Trąbka słuchowa”, “Ossicles”: “Kosteczki słuchowe”, “Malleus”: “Młoteczek”, “Incus”: “Kowadełko”, “Stapes”: “Strzemiączko”, “Oval window”: “Okienko owalne”, “Round window”: “Okienko okrągłe”, “Cochlea”: “Ślimak”, “Basilar membrane”: “Błona podstawna”, “Organ of Corti”: “Narząd Cortiego”, “Semicircular canals”: “Kanały półkoliste”, “Otolith organs”: “Narządy otolitowe”, “Utricle”: “Łagiewka”, “Saccule”: “Woreczek”, “Otoliths”: “Otolity”, “Labyrinthine artery”: “Tętnica błędnikowa”, “Labyrinthine veins”: “Żyły błędnikowe”, “Vestibulocochlear nerve”: “Nerw przedsionkowo-ślimakowy”, “Olfactory epithelium”: “Nabłonek węchowy”, “Olfactory bulb”: “Opuszka węchowa”, “Olfactory nerve”: “Nerw węchowy”, “Cribriform plate”: “Blaszka sitowa”, “Mitral cells”: “Komórki mitralne”, “Anterior ethmoidal artery”: “Tętnica sitowa przednia”, “Ethmoidal veins”: “Żyły sitowe”, “Lingual artery”: “Tętnica językowa”, “Lingual veins”: “Żyły językowe”, “Meissner’s corpuscles”: “Ciałka Meissnera”, “Pacinian corpuscles”: “Ciałka Paciniego”, “Merkel cells”: “Komórki Merkla”, “Ruffini endings”: “Zakończenia Ruffiniego”, “Dorsal Column-Medial Lemniscus Pathway”: “Droga sznurów grzbietowych”, “Taste buds”: “Kubki smakowe”, “Fungiform papillae”: “Brodawki grzybowate”, “Foliate papillae”: “Brodawki liściaste”, “Circumvallate papillae”: “Brodawki okolone”, “Filiform papillae”: “Brodawki nitkowate”, “Facial nerve”: “Nerw twarzowy”, “Glossopharyngeal nerve”: “Nerw językowo-gardłowy”, “Vagus nerve”: “Nerw błędny”, “Anterior two-thirds of the tongue”: “Przednie dwie trzecie języka”, “Posterior one-third of the tongue”: “Tylna jedna trzecia języka”, “Epiglottis”: “Nagłośnia”, “Hypodermis”: “Tkanka podskórna”, “Epidermis”: “Naskórek”, “Dermis”: “Skóra właściwa”, “Keratinized stratified squamous epithelium”: “Rogowaciejący wielowarstwowy nabłonek płaski”, “Retinal photoreceptors”: “Fotoreceptory siatkówki”, “Photoreceptor layer”: “Warstwa fotoreceptorowa”, “Bipolar cell layer”: “Warstwa komórek dwubiegunowych”, “Ganglion cell layer”: “Warstwa komórek zwojowych”, “Cranial nerve VIII”: “Nerw przedsionkowo-ślimakowy”, “Cranial nerve I”: “Nerw węchowy”, “Perforated ethmoid bone”: “Blaszka sitowa kości sitowej”, “Tastants”: “Substancje smakowe”, “Retinal venous drainage”: “Drenaż żylny siatkówki”, “Macula lutea”: “Plamka żółta”, “Retinal metabolism”: “Metabolizm siatkówki”, “Central macular vision”: “Centralne widzenie plamkowe”, “Lens”: “Soczewka”, “Iris”: “Tęczówka”, “Biconvex”: “Dwuwypukły”, “Retina”: “Siatkówka”, “Capsule”: “Torebka”, “Cortex”: “Kora”, “Nucleus”: “Jądro”, “Refractive properties”: “Właściwości refrakcyjne”, “Scotopic vision”: “Widzenie skotopowe”, “Photopic vision”: “Widzenie fotopowe”, “Wavelengths”: “Długości fal”, “Choroidal vessels”: “Naczynia naczyniówki”, “Internal carotid artery”: “Tętnica szyjna wewnętrzna”, “Superior ophthalmic vein”: “Żyła oczna górna”, “Inferior ophthalmic vein”: “Żyła oczna dolna”, “Oculomotor”: “Okoruchowy”, “Trochlear”: “Bloczkowy”, “Abducens”: “Odwodzący”, “Auditory”: “Słuchowy”, “Vestibular”: “Przedsionkowy”, “Ear canal”: “Przewód słuchowy”, “Nasopharynx”: “Nosogardło”, “Middle ear”: “Ucho środkowe”, “Cochlear fluid”: “Płyn ślimakowy”, “Calcium carbonate crystals”: “Kryształy węglanu wapnia”, “Basilar artery”: “Tętnica podstawna”, “Vestibular apparatus”: “Narząd przedsionkowy”, “Anterior inferior cerebellar artery”: “Tętnica przednia dolna móżdżku”, “Inferior petrosal sinus”: “Zatoka skalista dolna”, “Jugular vein”: “Żyła szyjna”, “Nasal cavity”: “Jama nosowa”, “Olfactory receptor neurons”: “Neurony receptorowe węchowe”, “Mucus layer”: “Warstwa śluzowa”, “Cilia”: “Rzęski”, “Trigeminal nerve”: “Nerw trójdzielny”, “Papillae”: “Brodawki”, “Taste receptor cells”: “Komórki receptorowe smaku”, “Prominent”: “Wyraźny”, “External carotid artery”: “Tętnica szyjna zewnętrzna”, “Internal jugular vein”: “Żyła szyjna wewnętrzna”, “Somatosensory cortex”: “Kora somatosensoryczna”, “Peripheral Nerves”: “Nerwy obwodowe”, “Spinal cord”: “Rdzeń kręgowy”, “Parietal lobe”: “Płat ciemieniowy” }; // Normalize keys in the dictionary const normalizedWordsToTooltip = {}; for (const [key, value] of Object.entries(wordsToTooltip)) { const cleanedKey = key.replace(/(.*?)/g, ”).trim(); // Remove anything in parentheses normalizedWordsToTooltip[cleanedKey.toLowerCase()] = value; } function processNode(node) { if (node.nodeType === Node.TEXT_NODE && node.nodeValue.trim()) { let content = node.nodeValue; // Regex to match only the main words (ignores parentheses) const regex = new RegExp( `\b(${Object.keys(normalizedWordsToTooltip).join(‘|’)})\b`, ‘gi’ ); if (regex.test(content)) { const wrapper = document.createElement(‘span’); wrapper.innerHTML = content.replace(regex, (match) => { const tooltip = normalizedWordsToTooltip[match.toLowerCase().trim()]; return `${match}`; }); node.replaceWith(wrapper); } } 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Visual System

The eyes are the sensory organs responsible for vision. They are located in the orbital cavities of the skull, which offer protection and support. The eyes are complex structures, designed to capture and focus light, allowing for the perception of the environment.

Key Anatomical Structures

• Cornea: The cornea is the transparent, dome-shaped front surface of the eye, covering the iris, pupil, and anterior chamber. Composed of five layers, it is avascular (lacking blood vessels), making it crucial for clear vision. Its primary function is to refract light, directing it toward the retina. The cornea provides about 75% of the eye’s total refractive power. It is highly innervated, contributing to its sensitivity to pain and touch.
• Lens: Located behind the iris, the lens is a flexible, biconvex structure that focuses light onto the retina. Its ability to change shape—controlled by the ciliary muscles—allows for accommodation, which enables the eye to focus on objects at various distances. The lens is composed of a capsule, cortex, and nucleus, with the cortex and nucleus responsible for refractive properties.

• Iris: The colored part of the eye that controls the size of the pupil, thereby regulating the amount of light entering the eye. It functions like the aperture of a camera, adjusting to different lighting conditions.
• Sclera: The tough, fibrous outer layer of the eye, often referred to as the “white of the eye.” It provides structural integrity and protection.
• Choroid: The choroid lies between the retina and sclera and is richly vascularized, supplying oxygen and nutrients to the outer layers of the retina.
• Retina: The retina is the innermost layer of the eye and contains the photoreceptor cells—rods and cones—that convert light into neural signals. The retina is divided into several layers, including the photoreceptor layer, bipolar cell layer, and ganglion cell layer. The retina is a complex, multi-layered tissue essential for vision, and it includes a macula, which contains the fovea, the point of sharpest vision.

Photoreceptors in the Retina

• Rods: Located mainly in the peripheral regions of the retina, rods are extremely sensitive to low light levels and are responsible for scotopic (night) vision. They play a significant role in detecting movement but do not contribute to color vision.

• Cones: Concentrated in the central part of the retina, particularly in the fovea, a small depression in the retina that provides the sharpest vision. Cones are responsible for photopic (daytime) vision and color perception. There are three types of cones based on their sensitivity to different wavelengths of light:
  1. S-cones: Sensitive to short wavelengths (blue light).
  2. M-cones: Sensitive to medium wavelengths (green light).
  3. L-cones: Sensitive to long wavelengths (red light).

Retinal Structure

The retina is a highly organized, multi-layered structure that includes:

• Photoreceptor Layer: Contains the rods and cones.
• Bipolar Cells: These cells relay signals from the photoreceptors to the ganglion cells.
• Ganglion Cells: The axons of these cells converge to form the optic nerve, which transmits visual information to the brain.

Blood Supply

• The eye’s blood supply is derived mainly from the ophthalmic artery, a branch of the internal carotid artery. The retina receives its blood from the central retinal artery and the choroidal vessels. These systems ensure that the retina, a metabolically active tissue, receives a constant supply of oxygen and nutrients.

Venous Drainage

• Venous blood from the eye is drained primarily by the central retinal vein and the vortex veins, which drain into the superior and inferior ophthalmic veins.

Innervation

• The eyes are innervated by several cranial nerves, with the optic nerve (II) transmitting visual information from the retina to the brain. The oculomotor (III), trochlear (IV), and abducens (VI) nerves control eye movement.

Auditory and Vestibular Systems

The ear is a dual-function sensory organ responsible for hearing (auditory system) and balance (vestibular system). Each component of the ear plays a specific role in capturing sound waves and detecting head movements.

Key Anatomical Structures

• Outer Ear: The outer ear is composed of the auricle (pinna) and the external auditory canal. The auricle is the external, visible part of the ear that collects sound waves and channels them toward the tympanic membrane (eardrum), which vibrates in response to these waves. The auricle also helps to protect the ear canal from foreign objects.

• Middle Ear: The middle ear is located between the eardrum and the inner ear. It contains the Eustachian tube, which connects the middle ear to the nasopharynx and helps maintain proper pressure balance. Additionally the middle ear houses three small bones called ossicles, which amplify sound vibrations:
  1. Malleus (Hammer): Attached to the tympanic membrane.
  2. Incus (Anvil): Positioned between the malleus and the stapes.
  3. Stapes (Stirrup): The smallest bone in the human body, connecting to the oval window of the cochlea in the inner ear. The ossicles amplify sound vibrations and transmit them from the outer ear to the inner ear.

• Inner Ear: The inner ear, housed within the temporal bone, consists of two main structures: the cochlea and the vestibular apparatus.

The Cochlea is a spiral-shaped, fluid-filled structure that converts sound vibrations into neural signals. It contains several important related structures, including:

1. Basilar Membrane: Runs through the length of the cochlea, supporting the organ of Corti, the primary sensory organ of hearing. Hair cells on the basilar membrane detect mechanical changes caused by sound waves and convert them into electrical signals.
2. Oval Window: The membrane-covered opening connecting the middle ear to the cochlea, transmitting sound vibrations into the cochlear fluid.
3. Round Window: A second membrane-covered opening that allows fluid displacement within the cochlear duct, facilitating proper sound wave transmission.

The Vestibular Apparatus is essential for maintaining equilibrium and coordinating head and eye movements. It includes:

1. Semicircular Canals: Three fluid-filled canals positioned at right angles to each other, detecting angular acceleration and head rotation.
2. Otolith Organs: Comprising the utricle and saccule, these organs detect linear acceleration and head tilts. They contain otoliths (small calcium carbonate crystals) that shift with movement, stimulating hair cells and sending balance-related signals to the brain.

Blood Supply

• The blood supply to the ear primarily comes from the labyrinthine artery, a branch of the anterior inferior cerebellar artery or the basilar artery, supplying both the cochlea and vestibular apparatus.

Venous Drainage

• Venous blood is drained via the labyrinthine veins, which connect to the inferior petrosal sinus and jugular vein.

Innervation

• The auditory and vestibular functions are transmitted by the vestibulocochlear nerve (cranial nerve VIII). The cochlear branch carries auditory signals, while the vestibular branch transmits balance-related information.

Olfactory System

The olfactory system is responsible for detecting and processing odors. The primary sensory organ for this system is the nose, specifically the olfactory epithelium, which is located in the roof of the nasal cavity.

Key Anatomical Structures

• Olfactory Epithelium: A specialized epithelial tissue that contains olfactory receptor neurons. These neurons possess cilia that extend into the mucus layer of the nasal cavity. When odor molecules bind to receptors on these cilia, they trigger a biochemical cascade that generates an electrical signal.
• Olfactory Bulb: Located just above the nasal cavity, the olfactory bulb is the first processing center for olfactory information. It receives signals from the olfactory receptor neurons and relays them to higher brain regions.
• Olfactory Nerve (Cranial Nerve I): The axons of the olfactory receptor neurons form the olfactory nerve, which transmits signals from the olfactory epithelium to the olfactory bulb.

Olfactory Pathways

• Cribriform Plate: A perforated section of the ethmoid bone through which the olfactory nerve fibers pass, connecting the olfactory epithelium to the olfactory bulb.
• Mitral Cells: The primary relay neurons in the olfactory bulb, which process olfactory signals and transmit them to the olfactory cortex, amygdala, and hippocampus, linking the sense of smell to memory and emotion.

Blood Supply

• The olfactory region is supplied by branches of the anterior ethmoidal artery, a branch of the ophthalmic artery, ensuring adequate oxygenation to the olfactory structures.

Venous Drainage

• Venous blood from the olfactory system is drained via the ethmoidal veins, which connect to the cavernous sinus.

Innervation

• The olfactory nerve (cranial nerve I) is responsible for the transmission of olfactory information to the brain, while branches of the trigeminal nerve (cranial nerve V) provide general sensory innervation to the nasal cavity.

Gustatory System

The tongue is the main organ responsible for the sense of taste. It is a muscular structure located in the oral cavity and covered with papillae that contain taste buds.

Key Anatomical Structures

• Taste Buds: Located primarily on the papillae of the tongue, taste buds contain taste receptor cells that respond to different chemical stimuli (tastants). Each taste bud consists of 50–100 taste receptor cells.

Papillae Type	Description
Fungiform Papillae	Found on the anterior portion of the tongue, these papillae contain a high density of taste buds.
Foliate Papillae	Located on the lateral aspects of the tongue, they are more prominent in children and decrease in number with age.
Circumvallate Papillae	Positioned at the back of the tongue, arranged in a V-shape. They are the largest papillae and contain numerous taste buds.
Filiform Papillae	The most numerous papillae on the tongue, covering the dorsal surface. They do not contain taste buds but are important for the mechanical aspect of sensing texture.

Gustatory Pathways

• Cranial Nerves: The taste information from the taste buds is transmitted via three cranial nerves:
  1. Facial Nerve (Cranial Nerve VII): Carries taste sensations from the anterior two-thirds of the tongue.
  2. Glossopharyngeal Nerve (Cranial Nerve IX): Transmits taste information from the posterior one-third of the tongue.
  3. Vagus Nerve (Cranial Nerve X): Carries taste sensations from the throat and epiglottis.

Blood Supply

• The tongue receives blood from the lingual artery, a branch of the external carotid artery.

Venous Drainage

• The venous blood from the tongue drains via the lingual veins into the internal jugular vein.

Somatosensory System

The skin is the body’s largest organ and serves as the primary organ for the somatosensory system. It is responsible for detecting various types of physical stimuli, including touch, temperature, and pain.

Key Anatomical Structures

• Epidermis: The outermost layer of the skin, composed of keratinized stratified squamous epithelium. It contains free nerve endings that detect pain and temperature.
• Dermis: Beneath the epidermis, the dermis houses various sensory receptors, including:
  1. Meissner’s Corpuscles: Located in the dermal papillae, they are responsible for detecting light touch.
  2. Pacinian Corpuscles: Found in the deeper layers of the dermis, they detect deep pressure and vibration.
  3. Ruffini Endings: These receptors detect skin stretch and are involved in proprioception.
  4. Merkel Cells: Located at the base of the epidermis, these cells detect sustained pressure and texture.

• Subcutaneous Tissue: Also known as the hypodermis, this layer is composed of fat and connective tissue. It provides cushioning and insulation for the body and contains fewer sensory receptors, though it does contribute to the sensation of deep pressure.

Somatosensory Pathways

• Peripheral Nerves: Sensory receptors in the skin transmit signals through peripheral nerves to the spinal cord.
• Dorsal Column-Medial Lemniscus Pathway: This pathway carries touch and proprioception signals to the somatosensory cortex in the parietal lobe of the brain, where the sensations are interpreted.