Exam 18: Organelle Inheritance and the Evolution of Organelle Genomes

Certain mutations in non- Hox genes actually produce homeotic mutants due to a failure to modulate chromatin acetylation appropriately. This influence on cellular "memory" is called what?

What is the name of the Drosophila multinucleated cell formed early in development?

Drosophila mutations such as bcd, if homozygous in the mother, produce offspring with lethal defects, no matter what the genotype of the offspring. For some other genes, the mutant phenotype can be "rescued" by introducing a wild- type allele into the embryo. What is the reason for these different outcomes?

You are interested in the homeobox genes that may regulate the development of the common clover plant Trifolium subterraneum. To identify clones of the T. subterraneum genome that contain these homeotic genes, you would probe with a rice gene that contains what domain?

There is much controversy in the news-both scientific and popular-about the use of embryonic stem cells for research. These cells are grown as cell lines in culture, created by taking the inner cell mass from 5- day- old embryos. What is the center of the controversy?

In limb- positioning in tetrapods, the __________acts as an organizer to promote digit formation at the distal ends of limb buds.

Which structure in plants acts most like embryonic stem cells in animals?

If a cell from the blastoderm of the Drosophila embryo is committed to form the sixth abdominal segment of the adult and this cell is transplanted into the thorax- committed region of another embryo, will it develop properties of a thoracic or an abdominal segment?

Epistasis analysis in single and double mutants, such as in the genes specifying genital development in C. elegans has helped to identify genes that function in developmental________.

An embryonic stem cell has the potential to differentiate into any cell or tissue type. Is it differentiated, pluripotent, or totipotent?

The Antennapedia complex and the bithorax complex of genes all encode transcription factors that have a 180- bp DNA- binding domain. What is this domain called?

Describe aspects of plant and animal development that are shared and then give specific evidence that plants and animals independently evolved mechanisms of multicellular development?

Holoprosencephaly is a highly variable condition in mammals, including humans. Its effects range from an absence of brain areas, mid- face disorders, and cyclopia to slight dental abnormalities. One form, HPE3, is caused by null mutations in Shh. Familial cases are inherited as a dominant trait. Which of the following do you expect?

As a Drosophila larva molts and becomes a pupa, most of the larval tissues die and adult structures are formed from cells in clusters known as imaginal discs that have remained unchanged throughout the larval stages. Therefore, the disc cells are_________ .

Null mutations in __________ genes would be expected to result in the failure to establish the anterior- posterior poles of an embryo

Certain species of lilies, if eaten by pregnant ewes, can cause the ewes to produce lambs with severe birth defects because the cyclopamine that the plant produces can block embryonic response to Shh. This type of birth defect is a phenocopy of mutations in which genes?

A homeotic mutant flower has an arrangement (from outside in) of carpels, stamens, stamens, carpels instead of the usual sepal, petals, stamens, carpels. In general, Class A genes specify sepals, Class A and B genes specify petals, Class B and C genes specify stamens, and Class C specifies carpels. This mutant must therefore have a mutation in_________ .

Most of the genes controlling development encode either signal molecules or _________.