Develop Of Multicellular Organisms 2

Question 1

What is phase 1 of neuronal development

Answer 1

“I am by myself” cell survival via a lot of cell division and proliferation. Develop independently of each other

Question 2

What is phase 2 of neuronal development

Answer 2

Cell body will throw out connections with anything; cannot delineate between axon and dendrites. Just wats to have a function and connection with a partner cell

Question 3

What is phase 3 of neuronal development?

Answer 3

Refinement of connections and merging of function via electrical signals

Question 4

Neurons and glial cells develop from what gastrula layer

Answer 4

Ectoderm

Question 5

CNS composes what?

Answer 5

Neural tube ie brain, spinal cord, retina

Question 6

PNS composes what?

Answer 6

Neural crest ie nerves and sensory neurons

Question 7

What is on the dorsal side of embryo?

Answer 7

Neural groove

Question 8

Neural gradually deepens as __ become elevated

Answer 8

Neural folds

Question 9

Neural folds meet, coalesce, and convert groove into closed __

Answer 9

Neural tube

Question 10

Center of neural tube is __

Answer 10

Neural canal

Question 11

What pathway controls differentiation (lateral inhibition and positive feedback)

Answer 11

Delta Notch

Question 12

The roof of the neural tube is the dorsal or ventral side?

Answer 12

Dorsal (BMP)

Question 13

The floor of the neural tube is the dorsal or ventral side?

Answer 13

Ventral (Hedgehog)

Question 14

Neural crest is at __ end

Answer 14

Dorsal end

Question 15

Fate of the neural crest cell depends on where they migrate to settle: 1st born present in __ layer and last born present in __ layer

Answer 15

1st born = inner layer

Last born = outer layer

Question 16

The tip of axon/dendrite has irregular spiky enlargement called the

Answer 16

Growth cone

Question 17

Axon-specific proteins will become __ and everything else __

Answer 17

Axon specific proteins will become AXONS and everything else DENDRITES

Question 18

What are the 2 monomeric GTPases that control actin assembly and disassembly

Answer 18

Rho and Rac

Question 19

Growth cones throw out: (they are rich in actin)

Answer 19

Filopodia and lamelopodia

Question 20

Axon is rich in:

Answer 20

Microtubules

Question 21

ECM has predictable routes of travel for neurons based on what 2 classes of homophilic cell adhesion molecules

Answer 21

Immunoglobin superfamily and cadherin family

Question 22

Matrix molecules such as laminin favor __ outgrowth

Answer 22

Axonal outgrowth

Question 23

Matrix molecules such as chondroitin sulfate proteoglycans inhibit:

Answer 23

Growth

Question 24

Ventral clusters = what type of neurons

Answer 24

Motor neurons

Question 25

Commissural neurons originate at:

Answer 25

Roof plate of neural tube

Question 26

Commissural neurons move from roof plate to __ plate

Answer 26

Floor plate

Question 27

Commissural neurons move from floor plate toward:

Answer 27

The brain

Question 28

What are the repellent chemotactic factors

Answer 28

Slit and semaphorin

Question 29

What are the attractive chemotatic factors

Answer 29

Netrin

Question 30

How does netrin work:

Answer 30

Netrin secreted by cells of floor plate-> bind to receptor to cause Ca2+ channels to open-> extracellular Ca2+ enters->activates to extend filopodia and movement of growth cone-> cells move down towards the floor plate

Question 31

How do the repellent chemotactic factors function:

Answer 31

Slit secreted by midline cells -> slit repels growth cones and blocks entry to the midline -> growth cones encounter semaphorin -> trapped between 2 repellents and cells leave floor plate and move away

Question 32

If there are enough neurotrophic factors, neurons will form synapses. T/F?

Answer 32

True

Question 33

Nerve growth factors (NGF) are secreted by what kind of cells and promote what?

Answer 33

Secreted by partner cells and promote survival of specific sensory neurons

Question 34

What is the NGF receptor?

Answer 34

TrkA

Question 35

NGF comes from what family:

Answer 35

Neurotrophins

Question 36

What is the short term effect of NGF

Answer 36

Local, direct, rapid and independent. Effect on growth cone neurite extension

Question 37

What is the long term effect of NGF?

Answer 37

Effect on cell survival

Question 38

In phase 3 synaptic remodeling, compete for tectal neurons. T/F?

Answer 38

True

Question 39

What are tectal axons

Answer 39

Axons from cells in different regions of retina

Question 40

NMDA (glutamate) receptor is a channel that allows what inside?

Answer 40

Ca2+ for lasting change in synaptic strength

Question 41

How are new dendritic spines formed

Answer 41

APs cause neurotransmitters released causes learning and new dendrites are formed