unit 2 :( Flashcards
i hate this unit
homology
suggests relationships/similarities among species that evolved from a shared ancestor
homoplasy
similar features that evolved seperately
darwin’s 4 observations
- reproduction increases population unless limits factor it
- individuals in a species are not identical
- some variation among individuals is inherited
- not all offspring survive to reproduce
basic similarities across vertebrate nervous systems
- development from hollow dorsal neural tube
- bilateral symmetry
- segmentation
- hierarchial control
- seperate systems
- functional specialization
social brain hypothesis for cortex size
larger cortex necessary for handling complex social relationships
what did darwin do?
natural selection
what did mendel do?
created laws of inheritance
what did de vries do?
mutations occur in genes, which induces changes in organism’s characteristics
6 stages of development in neural system
- neurogenesis
- cell migration
- differentiation
- synaptogenesis
- neural cell death
- synapse rearrangement
neurogenesis
cells from inner neural tube divide and the type of cell is determined by intrinsic and extrinsic
intristic
genetic
extrinsic
cell-cell interactions
are vertebrates focused on intrinsic or extrinsic?
more focused on extrinsic and they are both with most of the neurons they will ever have
are invertebrates more focused on intrinsic or extrinsic?
intrinsic
cell migration
depends on CAMS
when does cell migration happen in primates?
done by birth
when does cell migration happen in rodents?
still some cell migration after birth
differentiation
genes determine cell fate and nearby cells can also induce fate
what happens to undifferentiated cells?
they can be placed into a new environment and develop (stem cells)
synaptogenesis
growth of axons and dendrites, which have growth cones at ends
what is axon growth guided by?
chemoattractants and chemorepellants
neuronal cell death
apoptosis
what keeps cells alive?
cell-cell interactions
synapse rearrangement
synapses are retracted and added