Lecture 13 Flashcards
in the off/resting state of monomeric g-protein coupled receptors, is RAS bound to GTP or GDP?
GDP in off state, GTP in on state
GTP-binding protein is an intermediate __
transducing molecule
effector proteins activate __ who can activate __
secondary messengers; a secondary effector, blah blah blah
secondary messenger targets are usually __ or __
protein kinases or protein phosphatases
cAMP is comprised of 2 __ and 2 __ = __
regulatory domains; catalytic domains; R2C2 complex
active catalytic subunits phoshorylate downstream targets and leads to regulation of __
neurotransmitter release, neurotransmitter synthesis, ion channel/receptor function, calcium homeostasis, cytoskeletal function, gene expression, synaptic plasticity
IP3 and DAG (diacylglycerol) cooperate (with __) to activate __
Ca; protein kinase C (PKC)
CREB is a __ factor – binds to certain __ thereby increasing or decreasing the __
cellular transcription; DNA sequences; transcription of downstream genes
in an unstimulated cell, creb is not __ but can become so through several different __
phosphorylated; signaling cascades
the mechanism of signaling cascades causing creb to be phosphorylated underlies the __ and allows us to get __
late-phase LTP effect; newly synthesized proteins
what do the senses do for us? (4)
perception, control of movement, regulation of internal organs, and maintenance of arousal
there are sensory systems for __ (examples __) and for __ (examples __)
external stimuli (visual, auditory, olfactory, gustatory, somatosensory) internal stimuli (temperature, blood sugar, pressure and CO2, muscle tension and joint position (proprioception)
another word for perception
exteroception
proprioception
a sense of our body in space, relative position, etc.
muscle spindles
proprioceptors in muscle
kinesthesia
the overall sense of position, movement, etc.
interoceptors
perception of things happening inside your body (gut)
2 parts of ANS (autonomic sensory system)
sympathetic (fight or flight) and parasympathetic (rest and digest, feed and breed)
4 basic attributes of sensory systems
modality (what sense it is), intensity (how strong it is), duration, and location (where is it processed and encoded)
each sensory system has __ structures devoted to that sensory function
subcortical and cortical
intensity of a stimulus is represented by __
action potential frequency
strength of a stimulus is encoded by __
the amount of neurotransmitter released
concept of sensory adaptation
how you don’t feel a chair you’ve been sitting on for a while until you think about it, or your clothes, etc.
each sensory neuron has a __ - a specific region in sensory space in which the stimulus will trigger __
receptive field; the depolarization of that neuron
transduction = __
converting sensory stimuli into neuronal electrical signals
the size of the receptive field determines __
the spatial resolution of that neuron/sensory system
secondary sensory neurons may have __ receptive fields
large or small
convergence of the signals onto the secondary neurons means that the secondary neuron has a __ receptive field and yields greater __
larger (its a combination of the receptive fields of the primary sensory neurons); greater sensitivity
non-convergence of the signals onto the secondary neurons mean that the secondary neuron has a __ receptive field and yields greater __
same size as primary sensory neuron (typically 1:1 ratio); greater spatial resolution
sensory information must be fine-tuned to achieve __
maximal discriminative capacity (by lateral inhibition)
concept of signal transduction
stimulus energy is converted into electrochemical energy
concept of neural encoding
key attributes of the stimulus must be represented in the signals of the primary sensory neuron
rods and cones are/aren’t firing all the time
its only when light hits them that they are __
are; hyperpolarized
