lifespan development of brain and behavior

what is the outer cellular layer of a developing embryo

ectoderm

what does the ectoderm form

the nervous system

when the notochord releases a protein, diffusing into the spinal cord and directs some cells to become motor neurons, what is this process called?

induction

what is induction

process in which a set of cells influences the fate of neighboring cells via secreting chemical factor that changes gene expression in target cell

how does induction influence the change in gene expression in a target cell

by secreting a chemical factor—dependent on type

when an embryotic mouse cells gene is disrupted, making it nonfunctional and that mouse produces offspring that are missing that gene, what is the resulting animal referred to

knockout organism

what is a knockout organism

an individual/animal in which a particular gene has been disabled by an experimenter

when a functional, manipulated copy of a gene is introduced into a mouse, what is the animal described as

transgenic

what does transgenic mean

an animal in which a new or altered gene has been deliberately introduced into the genome

what is a cell that has not yet been differentiated extensively and placed into a brain region referred to as

stem cells

what is a stem cell

cell that is undifferentiated and therefore can take on the fate of any cell that a donor organism can produce.

what does synaptogenesis refer to

establishment of synaptic connections as axons and dendrites grow.

what is the growth cone

growing tip of an axon or a dendrite.

what is the filopodia

a very fine, tubular outgrowths from the growth cone.

what is a chemoattraction

compounds that attract particular classes of axonal growth cones.

what are chemorepellents

compounds that repel particular classes of axonal growth cones

what can apoptosis also be reffered to as

cell death

what is apoptosis

developmental process during which “surplus” cells die.

what is the nerve growth factor (NGF)

substance that markedly affects the growth of neurons in spinal ganglia and in the ganglia of the sympathetic nervous system

what is the neurotrophic factor

target-derived chemical that acts as if it “feeds” certain neurons to help them survive

what is the brain-derived neurotrophic factor (BDNF)

protein, purified from the brains of animals, that can keep some classes of neurons alive

what are epigenetics

study of factors that affect gene expression without making any changes in the nucleotide sequence of the genes themselves

what is methylation

chemical modification of DNA that does not affect the nucleotide sequence of a gene but makes that gene less likely to be expressed