Untitled Deck Flashcards
(28 cards)
What does the cell body of a neuron contain?
Nucleus
The cell body is essential for the neuron’s metabolic activities.
What is the primary function of an axon?
Sends impulses
Axons transmit electrical signals away from the neuron’s cell body.
What are the three types of neurons?
- Sensory (to CNS)
- Interneuron (within CNS)
- Motor (to effectors)
Each type of neuron plays a distinct role in the nervous system.
How do signals cross the synapse?
Via neurotransmitters
Neurotransmitters are chemical messengers that facilitate communication between neurons.
What is homeostasis?
Maintaining a stable internal environment
Homeostasis is crucial for the proper functioning of biological systems.
What are the steps involved in homeostasis?
- Detecting change (stimulus → receptor)
- Response → returns body to normal (via negative feedback)
This process ensures that internal conditions remain stable despite external changes.
What factors are regulated by homeostasis?
- Temperature
- CO₂
- Glucose
- Water balance
Regulation of these factors is vital for overall health and function.
What is the sequence of the Stimulus-Response Model?
- Stimulus →
- Receptor →
- Control center →
- Effector →
- Response
This model illustrates how organisms respond to stimuli.
What is a reflex?
Rapid, involuntary response bypassing the brain
Reflexes are automatic responses that occur without conscious thought.
What is the function of the conjunctiva in the eye?
Protects cornea
The conjunctiva is a thin membrane that covers the front of the eye.
What is the role of the cornea?
Focuses light
The cornea is the transparent front part of the eye that helps to refract light.
What does the sclera do?
Protects eye
The sclera is the white outer layer of the eyeball that provides structure.
What is the function of the choroid?
Nourishes eye
The choroid contains blood vessels that supply nutrients to the eye.
What does the retina detect?
Light (rods & cones)
The retina converts light into neural signals for vision.
What controls the size of the pupil?
Iris
The iris adjusts the pupil size to regulate the amount of light entering the eye.
What is the function of the lens in the eye?
Focuses light
The lens changes shape to help focus light on the retina.
What maintains the shape of the eye?
Aqueous/Vitreous Humour
These fluids are essential for maintaining intraocular pressure.
What do ciliary muscles do?
Adjust lens shape
Ciliary muscles enable accommodation for near or far vision.
What does the optic nerve do?
Sends signals to brain
The optic nerve transmits visual information from the retina to the brain.
What is the function of the pinna in the ear?
Collects sound
The pinna is the visible part of the ear that helps direct sound waves.
What channels sound in the ear?
Ear canal
The ear canal transmits sound waves to the eardrum.
What vibrates with sound in the ear?
Ear drum
The eardrum converts sound waves into mechanical vibrations.
What is the role of the ossicles?
Amplify sound
The ossicles consist of three tiny bones that increase the intensity of sound vibrations.
What does the Eustachian tube do?
Equalizes pressure
The Eustachian tube connects the middle ear to the throat, helping to maintain pressure balance.
