developing embryo has 3 distinct layers...
ectoderm, mesoderm, and endoderm
At day 40 afetr conception, 3 swellings form at the ANTERIOR end of nueral tube...they become...
hindbrain, midbrain, and forebrain
cerebral cortex consists of four parts...which are?
Frontal, Occipital, Parietal, temporal
Overview of occipital lobe
processes visual information
-Case Study: Oliver sacks turned color blind
Overview of PArietal lobe (2)
- - Somatosensory information
-damage to parietal cortex can also lead to sensory neglect
Overview of Temporal lobe
processes auditory information, language comprehension and memory
Case Study: H.M, epileptic young man that could not form new memories
Overview of Frontal lobe
voluntary motor behavior, taste, smell, language production, emotion, problem solving and many more
Case Study: Phineaus Gage, got a pipe of his head. Changed his personality
3 other parts that are in the Telencephalon
Neuron as a conductor...(3)
-neuron is uniquely suited to send elctrical and (chemical) signlas
-W/o these signals we die
-Many poisons block electrical signaling in neurons
Why do body parts go numb when affected by poison?
neurons are not passing over because poison prevents them
quick description of cell membrane
seperates inside from outside
Neuronal and cellular membranes are made up of?
Lipids have two groups that are associated with polar and nonpolar group?
- *water loving
- *water fearing
-prevents free flow of molecules across the membrane
How do molecules go into the membrane?
there are channels that permit SELECT molecules to cross between the outside of the neuron and inside
quick description- The extracellular and intracellular environment
chemical composition of the fluid outside of a neuron and inside of a neuron are very different
ex) Salt: Sodium + and chloride -
The 4 main "players" (ions)
(main ions) Sodium
has a positive charge and is in greater concentration outside the cell than inside
(main types) Chloride
has a negative charge and is greater concentration outside of the cell than inside
(main types) Potassium
has a positive charge and is in greater concentration inside the cell than outside
(main types) Proteins
have a negative charge and are in greater concentration inside the cell than outside
main players have specific channels to move across the membrane. Which one is the exception?
- negatively charged proteins
- *they are stuck inside the cell
measure of seperation of charge
Seperation of chemicals lead to...
Seperation of charges leads to...
when an element is in high concentration in one place, it tends to move to an area of lower concentration
charge of one kind accumulates in one place it tends to move away to an area of different charge
ex) positive accumulates moves to an area of more negatives
(membrane potential) Na+ more concentrated outside the cell than inside if given the oppurtunity to move across the membrane itt will move into the neurons b/c... (2)
-of its concentration gradient and
- -of electrostatic pressure
- *inside of neuron is negatively charged
(membrane potential) K+ is more concentrated inside the cell relative to the outside, if given oppurtunity to move out of neurons b/c...
-of its concentration gradient and
-against its electrostatic pressure since the inside of the neuron is negatively charged
Net result: these forces to combine to drive only a little bit of K+ out of cell
Why does the neuron stay charged?
-only way ions flow through the membrane and back out
-each "main players" has a channel that is selectively permeable to it
-these ions are always open
helps restore the restoration process of a membrane
-it moves 2 Na ions out of cell for every 2 K ions into the cell