Lab 9 - Sensory Organs Flashcards
- How can we determine the minimal hearing threshold?
Increase the sound frequency until the test subject can hear the sound. the minimum hearing threshold is the first value (in Hz) at which the test subject can hear the sound
- Where in the body the cutaneous sensation is more accurate?
Palm, sole,lip, nose
- What is the role of the outer ear canal?
Forwarding the sound waves towards inner ear
- What is the role of the ossicles?
Amplify and transmit the signal to the inner ear ( cochlea)
- Describe Weber’s illusion :
Exact perception of certain objects is different on various skin regions due to the number of receptors located in the given area
- What is the unit of sound?
Decibels dB= 10 log (I1/I2)
- What is the measurement of sound?
Hz
- What is the area on the retina, which has most visual acuity?
-Macula luteum
- Where in the brain is vision processed?
Visual cortex of occipital lobe
- What are the junctions of ossciles in middle ear?
Little bones located in the middle ear:eardrum to hammer ,anvil, stirrup to cochlea
- Why does the distribution of colors vary in field of vision?
Different distribution of color sensitive receptors
- What is binocular disparity?
there is a given distance between the 2 eyes so an object projects to the fovea centralism of the retina in both eyes but all other points that are in front or behind project to other locations of retina
- Before reaching receptors cells, light refracts where?
the border of the cornea, the aqueous humour, the lens and the virtuous body)
- What is astigmatism?
Blurred vision due to inability of the optics of the eye to focus a point object into a sharp image on the retina
- Describe the genetic background of red-green color blindness:
Inheritable recessive alleles of X sex chromosome. Recessive allele in woman causes problems on heterozygote form, in man it is hemizygote
- Accommodation triad?
adaptable curvature of the lens, eye movements, pupil function
- Hearing range in human?
20-20000 Hz
- Why visual field isn’t circular?
Due to different structures on the face (e.g. nose, ears, etc.) might be covered
by some parts of the theoretical field of vision
- What are dB?
Scale measure for intensity of sound
- Viewing angle?
Max angle at which a display can be viewed with acceptable visual performance
- Measure of min viewing angle?
arcmin
- Methods to find the blind spot?
Mariotte card + perimeter
- Thermoreceptors?
Non specialized sensory receptor that codes absolute and relative changes in temp
- define blind spot of retina
The blind spot of retina is where the optic nerve, retinal arteries and vein leave the eye.
At this point, NO photosensitive receptors are located. So if an object projects into this spot, we are not able to see it=BLIND SPOT
- what is the biological explanation of the retinal after image?
Stimulation of ganglion cells of the retina do not cease immediately after ending of stimuli.
For example after lightning, we experience after-immage
- name 5 parts of the reflective arch
- Receptor activation
- After transduction, the Signal travels towards CNS through an AFFERENT nerve
- The Signal is processed in the CNS
- The Information reaches the EFFECTOR organ through an EFFERENT nerve
- The EFFECTOR organ executes the order from the CNS
- give an example of supporting roles (page 2)
Defending of receptors
Amplifying and modulating of signals
Adaptation is a neural process that can be devided into?
Sensory side
Acting side
(Center in CNS)
What are the three attributes for the sound waves?
wavelength (gamma)
frequency (f)
velocity (c)
Gamma=c/f
What is the outer canal responsible for?
Forwarding the sound onto the ossicles located in the middle ear causing delay according to the location of the sound source.
RAT: No delay
Why is the determination of the origin of sound important?
It is a combined result of registering the delay between the ears and,
recalling the memory!
What does the Rinne experiment demonstrate?
Demonstrates that how the sound is transferred from outer ear to the inner.
