Understanding Our Senses: How We See, Hear, Taste, and Feel

Understanding Our Senses

What do all the senses have in common?

The eye, the ear, the nostrils, and the tongue are organs adapted to capturing specific stimuli. They have a high concentration of specialized receptors.

The Ear

Outer ear: flap, external ear canal. Middle ear: eardrum, ossicles (small bones). Inner ear: semicircular canals, cochlea, Eustachian tube.

Why Avoid Loud Noises?

Loud noises can eventually cause hearing problems and, in extreme cases, a perforated eardrum.

How Do We Perceive Colors?

Inside our eyes are cells that function as sensors in the retina, called rods and cones.

Rods and Cones

• Rods: Activated in darkness, allowing us to distinguish black, white, and shades of gray. They enable us to perceive contrast.
• Cones: Work during the day and in illuminated environments, enabling color vision. The brain interprets this information, as the eye only captures light.

Thanks to light, we can differentiate shades and see colors. Some colors, like ultraviolet, are not visible to the human eye but can be perceived by cameras.

Why Does a Cold Affect Our Sense of Taste?

When you're ill, the membranes of your nasal cavity become inflamed and covered in mucus, reducing their ability to perceive aromas, which affects taste.

Definitions

Definitions of cornea, eyelid, eardrum, and optic nerve:

• Cornea: A transparent ocular tissue found on the surface of the eye. It protects the iris and lens and helps focus images on the retina.
• Eyelid: A mobile fold of skin (upper and lower) that covers the eyes, providing protection.
• Eardrum: An elastic, semitransparent, conical membrane that connects the external auditory canal to the middle ear, sealing the middle ear cavity.
• Optic Nerve: A sensory nerve responsible for transmitting visual information from the retina to the brain.

Functions of the Skin

• Protection: The skin is the body's first barrier, with fat glands and hairs (multiple cell layers).
• Sensitivity: The skin contains touch, pressure, pain, and temperature receptors.
• Color/Protection: Melanin provides skin color and protection.
• Excretion: Sweat glands regulate temperature and excrete toxins.

Why Are Lips More Sensitive Than the Back?

Lips have more receptors and nerve endings than the back.