BIO 305 Developmental Biology  Exam #1

 

NAME ______________________

 

EXAMPLE ANSWER.  Write your answers in complete sentences.  You donŐt need to underline key words, I just did that for this example.

 

What is a notochord?

 

The notochord is a transient structure formed during gastrulation from the mesoderm and found in all chordate embryos.  It induces the overlying ectoderm to form the neural tube by releasing signaling factors, like Noggin for example, that block BMP4 signaling.

 

 

Write a short answer to each of the following.  Two points each

20 points total

 

What is cell determination?

 

 

 

 

What is a maternal factor?

 

 

 

 

What is the trophectoderm?

 

 

 

 

What is the TGFb family?

 

 

 

 

What is the archenteron?

 

 

 

 

What is the coelom?

 

 

What is the blastocoel?

 

 

 

 

 

What is a fate map?

 

 

 

 

What is epigenesis?

 

 

 

 

 

What is a homeotic mutation?

 

 

 

 

 

The following is a two part question.  Each part is worth 5 points.

 

Part 1:  Draw a picture of a somite and label the major parts the somite gets subdivided into and what tissues they will make.

 

 

 

 

 

 

 

 

 

Part 2:  Draw and label the three major signaling factors that pattern the somite in the above question and the label the cells that secrete each of the three factors.

 

 

 

 

 

 

 

 

The following is a two part question.  Each part is worth 5 points. 

 

Part 1:  Give three examples of how the Hox gene cluster has changed during evolution to alter the body plan along the anterior/posterior axis. 

 

 

 

 

 

 

 

 

Part 2:  Describe what part of the signaling pathway changed in the DNA to lead to these differences for each of the three examples in the above question.

 

 

 

 

 

 

 

 

The following is a two part question.  Each part is worth 5 points. 

 

Part 1:  Draw three separate pictures of a mature frog egg to show the distribution in the egg cytoplasm of three maternal factors.

 

 

 

 

 

 

 

 

 

 

 

Part 2:  Describe the job each of these will do in the embryo.

 

 

 

 

 

 

 

 

Write a one or two word answer in the space provided.  Two points each

20 points total

 

1) _____________  Which of the three germ layers produces the central nervous system?

 

2) _____________  What are transcription factors called that donŐt bind directly to DNA?

 

3) _____________  What is the process called that begins during gastrulation and involves the movement of cells to create form?

 

4) _____________ Give an example of an animal that is a protostome?

 

5) _____________  What structure causes induction of the neural tube in vertebrates?

 

6) _____________  What binds to response elements?

 

7) _____________  What is the stage called at which all vertebrate embryos look similar?

 

8) _____________  What is the name of one of the proteins secreted from the Spemann organizer? 

 

9) _____________  What are two genes called from separate species that share a common ancestral gene?

 

10) _____________  What is the region of the fertilized frog egg cytoplasm called where b-catenin does not get degraded?

 

Each of the following is worth 5 points each.

10 points total

 

What was HaeckelŐs Biogenic Law and why was it wrong?

 

 

 

 

 

 

 

 

Describe three jobs that BMP4 does at different stages during frog development.

 

 

 

 

 

 

 

 

Answer the following question on the attached pages.

Describe chick embryogenesis from fertilization through neurulation.  Include and define as many of the terms as you can but don't describe the genes or proteins involved.

20 points