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• What are the desired learning outcomes for the class on special sense organs?

  Reflect, outline, and discuss special sense organs
• Why are special sense organs important in animals?

  They enable perception of environmental stimuli
• What are the specialized senses mentioned in the study material?

  Vision, hearing, balance, taste, and olfaction
• What organ is specialized for hearing and balance?

  The ear
• What is the shape of the eye?

  A hollow, slightly elongated sphere
• What are the three layers of tissue in the eye?

  Sclera, uvea, and retina
• What comprises the exterior layers of the eye?

  The sclera and cornea
• What is the function of the lens in the eye?

  To focus light onto the retina
• What divides the interior of the eye into anterior and posterior cavities?

  The lens suspended by zonular fibers
• What fills the anterior and posterior chambers of the eye?

  Aqueous humor
• What is the vitreous chamber filled with?

  The vitreous body or vitreous humor
• What are the microscopic layers of the cornea from outside in?

  Stratified squamous epithelium, Bowman’s membrane, stroma, Descemet’s membrane, simple squamous epithelium

  
• What is the white part of the fibrous tunic called?

  The sclera
• What contributes to the opacity of the sclera?

  Less organized collagen and elastic fibers
• What are the three parts of the vascular tunic?

  The iris, ciliary body, and choroid
• What is the function of the iris?

  To change the size of the pupil
• What does the ciliary body secrete?

  Aqueous humor
• What is the role of the choroid?

  To nourish the outer parts of the retina
• What are rods and cones?

  Photoreceptors in the retina
• What do rods primarily contribute to?

  Peripheral and night vision
• Where are cone cells primarily located?

  In the fovea
• What is the function of the organ of Corti?

  To translate sound vibrations into nerve impulses
• What are the three parts of the ear?

  External ear, middle ear, inner ear
• What is the function of the middle ear?

  To amplify incoming sound waves
• What fluid fills the inner ear?

  Endolymph
• What do the semicircular canals indicate?

  Rotational movement and orientation
• What increases the surface area of the tongue?

  Lingual papillae
• What do taste buds respond to?

  Chemical properties of food particles
• Where are olfactory receptors located?

  In the nasal cavity
• How do odor receptors function?

  They respond to multiple similar odorants
• What is olfaction tied to?

  Memory and emotion
• What are the types of lingual papillae and their characteristics?

  • Foliate: Located on the sides of the tongue, contain taste buds.
  • Circumvallate: Large, located at the back, contain taste buds.
  • Fungiform: Mushroom-shaped, scattered across the tongue, contain taste buds.
  • Filiform: Thread-like, cover most of the tongue, do not contain taste buds.
• Describe the mechanism of sound transmission in the ear.

  1. Sound waves enter the external ear.
  2. They vibrate the tympanic membrane.
  3. Vibrations are amplified by the ossicles.
  4. Vibrations travel to the oval window.
  5. They create waves in the endolymph.
  6. Hair cells in the organ of Corti convert vibrations to nerve impulses.
  7. Impulses travel to the brain via the vestibulocochlear nerve.
• What are the roles of the special sense organs in animals?

  • Vision: Perception of light and images.
  • Hearing: Detection of sound waves.
  • Balance: Orientation and stability.
  • Taste: Identification of flavors.
  • Smell: Detection of odors.
• What are the layers of the retina and their functions?

  • Photoreceptor outer segments: Contain rods and cones for light detection.
  • Outer nuclear layer: Contains cell bodies of photoreceptors.
  • Inner layers: Process visual information and transmit signals to the brain.
• What is the relationship between taste and smell?

  • Taste buds detect flavors.
  • Olfactory receptors detect odors.
  • Together, they create the perception of flavor in foods.
• What is the significance of the fovea in vision?

  • Densely packed with cone cells.
  • Provides acute vision for detailed activities.
  • Rod-free area for optimal light detection.
• What is the role of the ciliary body in the eye?

  • Secretes aqueous humor.
  • Controls the shape of the lens.
  • Supports the iris and pupil function.
• What is the function of the choroid in the eye?

  • Provides nutrition to the outer retina.
  • Contains blood vessels for oxygen supply.
  • Connects to the retinal pigment epithelium.
• What are the functions of rods and cones in the retina?

  • Rods: Sensitive to light, peripheral and night vision.
  • Cones: Function in bright light, provide color and detail.