BIOL205 Spring 2015 Lecture 3 1. To demonstrate whether a patch

26 Jun BIOL205 Spring 2015 Lecture 3 1. To demonstrate whether a patch

Question
BIOL205 Spring 2015 Problem sets for lectures 3, 4 and 5

Lecture 3

1. To demonstrate whether a patch of cells had the capacity to organize other cells of the embryo, what method or methods would you use? (Answer with 1-3 word descriptions of the method only – no further description of experiments / controls is necessary)

_______________________________________________________________

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2.

Select all that are true:

A) The darker shaded cells in the two images will become the same part of the

animal.

B) The darker shaded cells in the left embryo will be more anterior than the

darker shaded cells in the right embryo.

C) The darker shaded cells in the left and right embryos are at the lip of the

blastopore

D) The fate of the darker shaded cells in both embryos is determined at this

stage.

3. Select all that contribute to setting up the anterior-posterior axis in the

zygote of the nematode C. elegans.

Actin-myosin contractility

Liquid droplet coalescence

Microtubule cytoskeleton

Mutually exclusive cortical domains

Nuclear-cytoplasmic shuttling

Paracrine signalling

Transcriptional regulation

.0/msohtmlclip1/01/clip_image005.png”>.0/msohtmlclip1/01/clip_image006.png”>.0/msohtmlclip1/01/clip_image007.png”>.0/msohtmlclip1/01/clip_image008.png” alt=”Text box: x”>.0/msohtmlclip1/01/clip_image009.png”>4. Someone UV-irradiated this poor frog embryo at the late blastula stage. You kindly transplanted the organizer from an un-irradiated embryo of the same stage. Draw an arrow on the picture to indicate where a cell at the x will be a little while into the future.

Transplanted organizer

5. Put in order these factors that lead to the singularity and location of the point of gastrulation in the fruit fly Drosophila:

_____2___Germarium proximal-to-distal organization

_____3___Follicle cells induce oocyte polarization

_____6___Follicle cells deposit signal for the embryo

_____4___Oocyte becomes polarized

_____5___Oocyte induces dorsal fate of some follicle cells

____1____Stem cell divisions

6. Trace the information flow through the cell to induce Drosophila gastrulation.

(not all things will be used)

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Lecture 4

1. What is the building block of tissue and organ development? ____cell__________________

2. What is the name of the process of regulated cell death? ______apoptosis_____________

3. Regulated cell death involves a cascade of ______apoptotic bodies______.

4. Regulated cell death is important for:

A) development

B) disease

C) cell migration

D) holding a pencil

E) A, B and C

F) A, B and D

5. Imagine you did a mutagenic screen to identify mutant alleles of genes involved in vulval development. Name two kinds of defects that you could see with a low-power microscope that would you hope to find:

____________________________________ ______________________________________

6. Match the phenotype (effect) with laser-killing the anchor cell at these four times:

________Before fate specification of

the primary (middle) cell 1) vulva formed, eggs laid

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________After specification of the primary

cell but before specification of

the secondary cells

2) vulva not formed, eggs trapped

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________Immediately after the primary and

secondary fate cells are specified

________After cell fusion of the 3) vulva formed, eggs trapped

.0/msohtmlclip1/01/clip_image017.jpg” alt=”Photo on 3-27-14 at 10.40 pm.jpg”>pairs of vulval cells

7. Order the events important for development of the C. elegans egg-laying apparatus:

Cell fate specification _____

Cell fusion ______

Cell migration ______

Oriented cell division _____

8. Use one item from each column, in the assigned order, to complete three sentences about examples of information flow in cells:

1

2

3

4

Delta

Activated G protein

Kinase cascade

Spindle orientation

EGF

EGFR

Microtubule-motor interaction

Transcriptional activation

Plasma membrane

Notch

Proteolysis

_(1)_______________________ binding to _(2)_______________________ causes __(3)____________________, ultimately leading to__(4)_________________________________.

_(1)_______________________ binding to _(2)_______________________ causes __(3)____________________, ultimately leading to__(4)_________________________________.

_(1)_______________________ binding to _(2)_______________________ causes __(3)____________________, ultimately leading to__(4)_________________________________.

Lecture 5

1.Abdominal A, Antennapedia, Abdominal B, and Ultrabithorax, specify the regional identity of the Drosophila segments and are arranged in the same order on the chromosomes as the body segments they control. Collectively, they are called

____________________________.

2. Fruit fly embryos showing defects in every segment probably have a mutation in a

_________________________________ gene. Fruit fly embryos missing portions of every other

segment probably have a mutation in a ___________________________________ gene.

3.Name the 2 steps of the maternal-to-zygotic transition.

______________________________________________ ______________________________________________

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4.

The figure to the right shows the expression pattern of three genes during early Drosophila development. Genes with expression patterns like these fall into which class of genes? ________________

(Choose gene A, B or C)

The expression patterns of these genes are determined by the structure of their promoters.

Which gene (A, B or C) is most likely to have a promoter with high affinity binding sites for Bicoid protein, and to be turned off when Bicoid is bound? _____________

Which gene (A, B or C) is most likely to have low affinity binding sites for Bicoid and to be turned on only when all of the binding sites are occupied? ___________

Which gene (A, B or C) is most likely to have intermediate affinity for bicoid and to be turned on only when some of the binding sites are occupied? ___________________

In an embryo mutant for bicoid, where would Gene C be expressed? ______________

In an embryo genetically engineered to express high levels of Bicoid everywhere, where would Gene C be expressed? _______________________