Chapter 7: Life-Span Development of the Brain and Behavior Flashcards
Initial development occurs in the…
zygote and embryo
How many cell layers does the embryo develop?
3
Ectoderm
The outer cell layer = The NS
How long after implantation is development shown?
18-24 days
What is stage 1 of NS development?
Neurogenesis
What is stage 2 of NS development?
Cell Migration
What is stage 3 of NS development?
Differentiation
What is stage 4 of NS development?
Synaptogenesis
What is stage 5 of NS development?
Neuronal Cell Death
What is stage 6 of NS development?
Synapse Rearrangement
Neurogenesis
The cells on the inner side of the neural tube divide to create the ventricular zone.
Ventricular Zone
Cells from which all neurons and gila cells are derived
What is a cells birthdate?
The point at which they stop dividing.
What determines what kind of cell is born?
Intrinsic and Extrinsic factors (cell to cell interactions)
Intrinsic Factors of Neurogenesis
Genetic determination of a cell’s fate
Extrinsic Factors of Neurogenesis
Cells interact with each other to determine fate
Which type of factor makes it harder to predict a cell’s fate?
Extrinsic
Vertebrate Neuron Development
More focused on extrinsic factors and much less hardwired.
Invertebrate Development
More dependent on intrinsic factors
Vertebrates are born with…
Most of the neurons they will ever have.
Cell Migration
Neurons move from their original location to a new destination in the developing brain.
When is cell migration done in primates?
By birth
In what animal does cell migration occur after birth?
Rats
What is cell migration dependent on?
CAMS = Cell Adhesion Molecules
What do CAMS help guide in adulthood?
Axon cuts
Cell Differentiation
The development of intrinsic self organization.
Cell Autonomous
Genes determine cellular fate
Regulation
Adaptions of cells occur in response to early injuries.
Stem Cells
Cells are placed into a new environment and develop appropriately.
Synaptogenesis
The growth of neuronal processes (axons and dendrites)
Where do axons and dendrites have growth cones?
Their ends
What is axon growth guided by?
Chemicals
- Chemoattractants
- Chemorepellants
Apoptosis
Neuronal cell death
Where does cell death occur?
Throughout the entire body.
Apoptotic Process
- There is an influx of Ca2+ ions outside the cell, and an internal storage agent releases Ca2+ ions inside the cell.
- High levels of Ca2+ enter the mitochondria, and the Diablo Protein is released inside the cell.
- The Diablo Protein binds to IAP’s so they can no longer pass block the caspases (enzymes related to apoptosis).
- A small waterfall of caspases destroy the various proteins and DNA of the cell, making it incapable of survival.
- The family of Bcl-2 proteins can inhibit apoptosis by blocking the release of Diablo from the mitochondria.
Diablo Protein
A protein in the mitochondria that promotes apoptosis.
What helps keeps cells alive?
Cell to cell interactions
How do synaptic targets play a role in cell survival?
The synaptic targets provide neurotrophic factors. The cells that get enough survive.