Sensory Receptors and Stimuli Adaptation

Play an AI-generated podcast conversation about this lesson

What is the main function of the lens in the eye?

To regulate the amount of light entering the eye

To produce an image on the optic nerve

To absorb light and protect the eye

To refract light and focus it onto the retina (correct)

What happens to the image formed on the retina?

The image is formed upside-down on the retina (correct)

The image is blurry and unfocused

The image is right-side up

The image is projected directly onto the optic nerve

What is the main reason humans and most mammals cannot see infrared light?

Humans lack the necessary receptors to detect infrared light (correct)

Infrared light is not visible to the human eye

Infrared light is absorbed by the lens

Infrared light is not refracted by the lens

What is the main purpose of the lens in the eye?

To focus light onto the retina Signup and view all the answers

What is the composition of the lens in the eye?

The lens is composed of ≅1000 layers of cells that lose their nucleus and organelles during development Signup and view all the answers

What is the main symptom of Syringomyelia?

Weakness in hands Signup and view all the answers

Which condition is associated with bilateral loss of pain and temperature sensation?

Syringomyelia Signup and view all the answers

What is the characteristic symptom of Phantom Pain?

Sensation from amputated organs Signup and view all the answers

How does Herpes zoster reach the spinal ganglia?

Through retrograde transport Signup and view all the answers

Which area of the body does Phantom Feeling (phantom pain) typically originate from?

Sensory cortex Signup and view all the answers

What is a common consequence of Syringomyelia in terms of sensory perception?

Loss of pain sensation Signup and view all the answers

What type of receptors are Hair Follicle Receptors?

Phasic Signup and view all the answers

What constitutes a 'sensory unit'?

One sensory axon and its peripheral branches Signup and view all the answers

What determines the intensity of a stimulus?

Both the frequency of impulse transmission and the number of receptors involved simultaneously Signup and view all the answers

According to the Law of Specific Energies, what does not change as the intensity of a stimulus increases?

The type of sensation (modality) Signup and view all the answers

Which of the following can affect senses through central excitation or central inhibition states of the nervous system?

Both opiates and Calcitonin Gene-Related Peptides (CGRP) Signup and view all the answers

Which part of the body has the highest two-point discrimination ability?

Fingertips or lips Signup and view all the answers

What type of receptors are responsible for proprioception, fine touch, and fine pressure?

Muscle spindles, Golgi tendon organs, and Ruffini endings Signup and view all the answers

Which law states that all sensory fibers enter the spinal cord via dorsal roots, and all motor fibers leave the spinal cord via ventral roots?

Bell-Magendie law Signup and view all the answers

Which structure is the first neuron in the dorsal column-medial lemniscus system?

Spinal ganglion (dorsal root ganglion) Signup and view all the answers

Which symptom is associated with lesions in the dorsal column-medial lemniscal system?

Ataxia (drunken-like walking, swinging during eyes closed) Signup and view all the answers

Which structure is the third neuron in the dorsal column-medial lemniscus system?

Ventral posterolateral nucleus of the thalamus Signup and view all the answers

What type of neurotransmitter do all sensory fibers release?

Glutamate Signup and view all the answers

What is the role of HCO3− in saliva?

Reducing the taste intensity of acid Signup and view all the answers

Which enzyme catalyzes the formation of H2CO3 in intracellular fluid?

Carbonic anhydrase Signup and view all the answers

What is the primary active process involved in transporting H+ and K+ against their electrochemical gradients?

H+-K+ ATPase Signup and view all the answers

Which drug is used to inhibit the H+-K+ ATPase in gastric parietal cells?

Omeprazole Signup and view all the answers

What is responsible for the 'alkaline tide' observed in gastric venous blood after a meal?

HCO3− absorption Signup and view all the answers

How is Cl− transported into the lumen of the stomach?

Simple diffusion Signup and view all the answers