Ch. 4 pt 2

Question 1

_______: a proximate interaction where one cell changes the behavior of another cell

Answer 1

induction

Question 2

_______ cell produces signal, and _______ cell/tissue induced by signal

Answer 2

inducer
responder

Question 3

_______: the ability to respond to an inducing signal

Answer 3

competence

Question 4

In order for a cell/tissue to be competent, it must have a _______ allowing it to receive the signal

Answer 4

receptor

Question 5

_______ optic vesicle induction experiments were used to show induction and competence interactions

Answer 5

Xenopus
(slide 19)

Question 6

In amphibians, the first inducer of the lens may be the _______ and heart-forming _______ that underlie the lens-forming ectoderm during early and mid gastrula stages

Answer 6

foregut endoderm
mesoderm

Question 7

in amphibians, the Second inducer appears to be the ______ promoting the production of Pax6 TF in the neural ectoderm

Answer 7

neural plate

Question 8

The neural plate promotes the production of _______ in the neural ectoderm

Answer 8

Pax6

Question 9

_______ provides competence for lens ectoderm to respond to inducers from the optic cup cells

Answer 9

Pax6

Question 10

What are the steps to mouse lense formation? (6)

Answer 10

1) optic vesicle induces ectoderm to form lens placode
2) lens placode induces optic vesicle to form optic cup
3) Optic cup induces lens placode to invaginate
4) invagination induces optic cup to form 2 layer retina
5) Futher invagination forms lens vesicle and lens capsule
6) lens placode induces ectoderm to form cornea

Question 11

What is the optic vesicle?

Answer 11

neural ectoderm

Question 12

thickening on surface ectoderm in mouse lense formation is called

Answer 12

lens placode

Question 13

What are the 2 modes of induction?

Answer 13

1) instructive interactions
2) permissive interactions

Question 14

_______: a signal from the inducing cell is NECESSARY for initiating new gene expression in the responding cell

Answer 14

instructive interactions

Question 15

_______: in this type the responding cell already has been specified, it just needs the correct environment and signals to allow the expression of those traits

Answer 15

permissive interactions

Question 16

_____ organs are composed of an epithelium and an associated group of mesenchyme

Answer 16

ALL

Question 17

what are the two types of specification commonly dealt with in epithelial-mesenchymal interactions?

Answer 17

1) region specification
2) Genetic specificity of induction

Question 18

_______: interactions between epithelium and mesenchyme can create regionally specified structures

Answer 18

region specification

Question 19

_______: mesenchyme may instruct epithelium as to which genes to activate, but epithelium can only comply so far as the genome permits

Answer 19

genetic specification of induction

Question 20

Sperman and Schotte transplanted flank ectoderm from a _______ grastrula onto the region of a _______ gastrula destined to become the mouth, and vise-versa

Answer 20

frog
newt

Question 21

The _______ larvae developed mouthparts in the correct location, however, the specific structures made were those from the _______ ectoderm embryo

Answer 21

chimeric
original
- the ectoderm responded to the mesoderm by making the only mouth it “knew” how to make

Question 22

In drosophilia respitory system, reorganization of the cells in each sac produce primary, secondary, and tertiary branches without _______ or _______

Answer 22

cell division or apoptosis

Question 23

Tracheal development in drosophilia is initiated when nearby cells secrete _______, which is a _______, bound to cell membrane receptors on epithelial cells

Answer 23

Branchless protein (BNL)
chemoattractant

Question 24

The cells receiving the most signal are attracted and migrate towards the signal via changes in _______ and _______

Answer 24

cytoskeleton
cadherin expression

Question 25

Leaders cells express the _______ protein

Answer 25

Breathless protein (BTL)

Question 26

_______ cells guide the rest of the surrounding cells to become the tracheal tube

Answer 26

leader

Question 27

_______: a diffusible molecule that affects distance cell fates by concentration

Answer 27

Morphogen

Question 28

What does Morphogen mean in greek?

Answer 28

Form-Giver

Question 29

Morphogen are _______ produced in the cell or secreted _______

Answer 29

transcription factors
paracrine factors

Question 30

_______: cell(s) producing the morphogen
- transmitting cell

Answer 30

source

Question 31

_______: receiving cells affected by the morphogen

Answer 31

sink

Question 32

Morphogen act in _______: action on the receiving cell is dependent on concentration

Answer 32

analog

Question 33

What is the morphogen explained in xenopus development?

Answer 33

activin

Question 34

activin, a paracrine factor in the ______ family was embedded into beads and placed on unspecified cells in the xenopus experiment

Answer 34

TGF-B

Question 35

Explain what activin does to unspecified cells in:
1) high concentrations
2) medium concentrations
3) low concentrations

Answer 35

1) induced expression of googsecoid (dorsal structures)
2) induced Xbra (muscles)
3) normal development into blood vessels and heart

Question 36

For a ligand to induce a cellular response, it must bind to a receptor, which starts a _______ of events within the cell that ultimately regulate a response

Answer 36

cascade

Question 37

What are the 2 usual end points of signal transduction cascades?

Answer 37

1) regulation of transcription factors
2) remodeling of the cytoskeleton

Question 38

What is the most common receptor that has enzymatic function and can be activated?

Answer 38

Receptor Tyrosine Kinase (RTK)