Chapter 1 Stimuli And Responses Flashcards
The Brain and Spinal Cord is located in?
Central Nervous System
Where are the Cranial NERVES and Spinal NERVES located in?
Peripheral Nervous System
MAIN Function of the Human Nervous System (1m)
Control and Coordinates organs and parts of the body
Functions of the human nervous sytem
Detects stimuli and send information in the form of impulses
What are voluntary actions?
are Conscious actions that are conducted under one’s will
Voluntary actions are controlled by what?
Brain
Examples of voluntary actions
Reading, Writing, Speaking
What are involuntary actions?
Actions that occur immediately WITHOUT conscious control or prior thoughts
What part of the body controls the involuntary actions?
Medulla Oblongata and Spinal Cord
Actions that involve medulla oblongata
Heartbeat, breathing, peristalsis
Actions that involve spinal cord
Withdrawing hand when touching a hot object
Sneezing wwhen dust enters nose
Importance of the human nervous system
Carry out processes in the body such as breathing and body movements
What are the 5 sensory organs?
Eyes, ear, nose, tongue, skin
What are the photoreceptors in the retina?
Rod cells
Cone cells
Explain more about rod cells and cone cells
Rod cells are sensitive to different light intensities but are not sensitive to colours of light while cone cells are sensitive to colour of lights under bright conditions
what are the different types of cone cells?
Red, green and blue light
Job of earlobe
Collects and directs sound waves into the ear canal
Job or ear canal
Directs sound waves into the ear drumJ
Job of eardrum
Vibrates according to the frequency of the sound waves received and transfers the vibrations to the ossicles
Job of ossicles
Amplify sound vibrations and transfer them to the oval window
Job of oval window
Collects and transfer sound vibrations from ossicles to the cochleaJ
Job of eustachian tube
Balances the air pressure on both sides of the eardum
Job of cochlea
Detects and converts sound vibration into nerve impulses
Job of Semicircular canals
Detects the positions of the head and help to balance the body
Job of Auditory nerve
Send nerve impulses from the cochlea to the brain to be interpreted
What are smells?
Chemical subtances present in the air
What is the fucntion of sensory cells for smell?
Sensory cells for smell are tiny and covered with a layer of mucus. Chemical substances in the air will dissolve in this layer of mucus and stimulate cells to produce nerve impulses to the brain to be interpreted
What are the tiny nodules on the tongue known as?
Papillae
what are the papillae covered in?
Taste buds
Function of taste buds?
when food is chewed, chemical substances in food dissolve in saliva and diffuse into the taste buds to stimulate taste receptors and produce nerve impulses
Types of receptors in the skin?
Pain, cold, heat, touch and pressure receptor`
How does the skin function?
when receptors on the skin are stimulated, nerve impulses are produced and sent through the nervous system to be interpreted
mechanism of hearing
Earlobe, ear canal, eardrum, ossicles, oval window, cochlea, auditory nerve, brain
Examples of limitations of sigh
Optical Illusions and blind spots
How does an optical illusion occur?
when an object seen differs from its actual state
what causes astigmatism?
Caused by the uneven curvature of the cornea and eye lens
How to correct astigmatism
Cylindrical Lenses
What causes short sightedness?
Eye lens too thick or eye ball too long
How to correct short sightedness?
Concave lenses
What causes long sightedness?
Eye lens too thin or eye ball too short
How to fix long sightedness?
Convex lens
Frequency of human ears?
20 - 20000 Hz
How does age affect the frequency range of hearing?
The older the person, the lower the frequency range of the person
How does loudspeaker work?
Amplifies sound to be heard from far away
What are examples of responses in plants?
Tropism and Nastic Movement
What is tropism
Directional response of plants to stimuli
Examples of tropism
Geotropism
Hydrotropism
Phototropism
Thigmotropism
What is nastic movement
Response towards a stimulus but does not depend on the direction of the stimulus
What is stereophonic hearing
Hearing using both ears
Importance of stereophonic hearing
Determine location of a source of sound
