Exam 2

Question 1

zygote

Answer 1

from fertilization to 4 days old

Question 2

blastula or blastocyst

Answer 2

hollow ball of cell forms around 4-5 days

Question 3

gastrula

Answer 3

3 layered ball of cells forms 7-10 days

Question 4

ectoderm

Answer 4

outer layer, forms skin and nervous systems

Question 5

mesoderm

Answer 5

middle layer, forms muscle blood and bone

Question 6

endoderm

Answer 6

inner layer, forms internal organs lungs liver intestines

Question 7

neural plate

Answer 7

part of the back ectoderm that forms the neural tube by folding in on itself

Question 8

neural tube

Answer 8

hollow tube of cells that eventually forms the spinal cord and brain

Question 9

neural crest

Answer 9

these cells eventually migrate out and form the peripheral nerves

Question 10

cell proliferation

Answer 10

the formation of two new cells from one cell

Question 11

cell migration

Answer 11

the movement of cells from one place to another

Question 12

cell differentiation and maturation

Answer 12

the process by which unspecialized stem cells or precursor cells take one their final specialized state

Question 13

synaptogenesis

Answer 13

the formation of a functional synapse between an axon from a presynaptic neuron and the dendrites of a post synaptic neuron

Question 14

myelination

Answer 14

the formation of myelin sheaths and neurons

Question 15

The process of neural migration

Answer 15

starts around 8-9 weeks post conception and is complete 2-3 months before birth

Question 16

two main types of migration

Answer 16

tangential and radial

Question 17

tangential

Answer 17

moving up/down or around

Question 18

radial

Answer 18

moving out from center

Question 19

Tangential migration of neural crest cells to form

Answer 19

Schwann cells and neurons in peripheral nerves

Question 20

Radial migration of cerebral cortical neurons to form

Answer 20

layers of the cerebral cortex

Question 21

The processes associated with neuronal maturation

Answer 21

chemical differentiation

morphological differentiation

Question 22

Chemical differentiation

Answer 22

hormones and other chemical signals activate master regulatory genes specific proteins done by birth

Question 23

master regulatory genes

Answer 23

genes that produce a protein that then turn on neuron

Question 24

morphological differentiation

Answer 24

cell taking on its adult form- dendrites and axons begin to form continues into childhood

Question 25

The role of chemoattractants and adhesion molecules in process of axonal extension

Answer 25

1) secretion of chemoattractants from the target cell that guide the axon to them
2) cell adhesion molecules that then grasp the axon and adhere it to the target cell

Question 26

Synaptogenesis process

Answer 26

starts during prenatal development and continues into late childhood

Question 27

Creation of proper synaptic structure by cellular activites in both neurons

Answer 27

1) pre synaptic neuron needs to synthesize and store neurotransmitter vesicles
2) post synaptic neuron needs to form and insert neurotransmitter receptors into membrane

Question 28

Neuronal cell death and synaptic pruning

Answer 28

post-synaptic cells secrete neurotrophins which promote survival of neurons. Neurons with a stronger connections get more neurotropic support those with weaker connections don’t and eventually die. This ‘scuplts’ away neurons with weaker connections, leaving only ones with strong functional connections

Question 29

Which regions of the brain undergo myelination first and which under go it last

Answer 29

Regions controlling basic sensory analysis and simple movement myelinate first, regions involved with decision making and impulse control myelinate last