Chapter 1 & 2 Flashcards
What is an axon?
portion of nerve cells specialised for relaying electrical signals over long distances
What are the three types of glial cells?
Astrocytes, oligodendrocytes, and microglial cells.
What is the name of the technique that stains the nucleolus and other structures?
Nissl method
What are afferent neurons?
nerve cells that carry info. fr. periphery toward the brain or spinal cord
What are efferent neurons?
nerve cells that carry info. away fr. the brain or spinal cord
What is a resting membrane potential?
A negative potential
What are Pacinian corpuscles?
receptor neurons that sense mechanical disturbances of the skin
What are active transporters?
proteins that actively move ions into or out of cells against the concentratn gradt
What are ion channels?
Allow ions to diffuse down concentratn gradient- selectively permeable to certain ions
Studies of the ionic basis of the action potential in squid giant axon found that
Decreasing sodium outside cell decreases size of action potential
What is the difference between equilibrium potential and membrane potential?
- Equilibrium potential: affected by concentration and electrical gradients of one ion.
- Membrane potential: affected by gradients of all ions.
The refractory period ends when
The sodium channels are no longer activated.
Active transporters
- Actively move selected ions against concentration gradient
- Create ion concentration gradients
Ion channels
- Allow ions to diffuse down concentration gradient
- Are selectively permeable to certain ions
Which statement regarding metabotropic and ionotropic receptors is true?
Ionotropic receptors: immediate effects
Metabotropic receptors: long-term effects
The end plate channels show
a regenerative opening pattern that propagates an action potential along length of muscle fibre.
An important factor determining whether a receptor-operated ion channel is inhibitory or excitatory is
an important factor determining whether a receptor-operated ion channel is inhibitory or excitatory is
What are the events in chemical synaptic transmission?
- Depolarization of the presynaptic terminal
- Opening of voltage-gated ion channels
- Activation of presynaptic, calcium-sensitive proteins
- Vesicle fusion with plasma membrane
- Diffusion of transmitter across the synaptic cleft
Recycling of synaptic vesicles is tracked using HRP as a vesicle marker. What will be the observed sequence of HRP movement?
Coated vesicle, endosome, vesicle reserve pool
What is a possible outcome for a neurotransmitter after release into the synaptic cleft?
Activation of G-protein-coupled receptor on postsynaptic cell
What is not a catecholamine?
Histamine
Cocaine acts by
blocking dopamine reuptake
Which is not a class of opioid peptides?
Endocannabinoids
What change can could be responsible for increasing the amplitude of an excitatory postsynaptic potential (EPSP)?
An increase in the amount of glutamate released into the synapse
Main reason that rods are more sensitive to light than cones is that
rod transduction mechanism provides greater signal amplification
By which mechanism are rod signals transmitted in conditions of low light?
Rod bipolar cells synapse on amacrine cells, which in turn synapse on cone bipolar cells
You measure changes in membrane potential in an ON-center bipolar cell that is exposed to light in the center of its receptive field. What response would you expect to see?
Depolarization due to decreased release of glutamate by the photoreceptor cell
The fovea
lies at the center of the macula lutea
What sequence represents the most direct pathway for the transmission of visual information from the eye to the brain?
Photoreceptor → bipolar cell → ganglion cell → brain
Two main functions of the retinal pigment epithelium are
- phagocytosis of shed outer segments
- regeneration of the photoreceptor photopigments
Which visual area is most specialized for processing color information?
V4
Contralateral visual field deficit is often due to
optic tract or cortical damage
What feature is not a characteristic of certain primary visual cortex neurons?
Recognition of faces
Semicircular canals are largely insensitive to linear acceleration because
the forces produced by linear acceleration are the same on both sides of the cupula
The vestibulo-ocular reflex is a mechanism for
stabilizing gaze during head movement
Patients with severe bilateral vestibular damage do not exhibit
difficulty in visually tracking slow-moving objects
Both the cochlea and the labyrinth use
hair cells in mechanotransduction
How transduction is biphasic?
Movements toward and away from the kinocilium can produce increased or decreased firing of vestibular afferents
Utricle is most sensitive to
horizontal acceleration of the head
Semicircular canals is designed to detect
angular acceleration
List functional specialisations of the bran
Fusiform face area (FFA): specialised for facial recognition located in the fusiform gyrus.
Visual word form area (VWFA):
The vestibulo-ocular reflex is a mechanism for
stabilizing gaze during head movement
Patients with severe bilateral vestibular damage do not exhibit
difficulty in visually tracking slow-moving objects
Both the cochlea and the labyrinth use
hair cells in mechanotransduction
How transduction is biphasic?
Movements toward and away from the kinocilium can produce increased or decreased firing of vestibular afferents
Utricle is most sensitive to
horizontal acceleration of the head
Semicircular canals is designed to detect
angular acceleration
List functional specialisations of the bran
Fusiform face area (FFA): specialised for facial recognition located in the fusiform gyrus.
Visual word form area (VWFA):
