Exam 18: Organelle Inheritance and the Evolution of Organelle Genomes

In Drosophila and other animals, Hox genes encode transcription factors that control development; but in Arabidopsis, a different family of transcription factors is produced with a different set of conserved amino acids. These are encoded by what group of genes?

In an organism such as a sea urchin, administration of actinomycin D prevents all mRNA synthesis. However, early development up to gastrula formation can take place in the presence of actinomycin D but gastrulation cannot. This implies that _________.

What term describes the process by which a cell acquires a certain fate from its neighboring cell?

During the evolution of development in animals, it is found that many regulatory genes have been co- opted for the development of different structures, such as limbs or digits. This is an example of what current area of research?

Cells called _________influence development by controlling other cells in their local environment?

Aniridia is a human condition in which the eye has no iris. The protein encoded by the gene responsible for aniridia is very nearly identical to the protein product of the fly Eyeless protein. What experiment could provide evidence that the two genes are functionally equivalent?

How and when does the Antennapedia complex change antennae into legs?

Mutations of regulatory elements of developmental genes may have either dominant or recessive effects. If a mutation deletes a silencer upstream of a HOX gene, which do you expect?

A pair- rule gene in Drosophila called runt controls nervous system formation. In the mouse, runt controls blood cell formation and genital structures. In humans, the analog of runt, when mutated, causes children to lack collar bones, and the opening at the top of the skull fails to close. What kind of experiment could tell you whether these genes are conserved in function?

Human Hox genes are in four clusters: HOXA, HOXB, HOXC, and HOXD, for a total of 39 genes. Besides conserving the clustering of genes, evolution has also conserved________ .

A mutation in a fly causes an antenna to develop where a leg should be. This is an example of a __________mutation.

Segmentation genes in Drosophila act in which of the following orders?

Cell autonomous genes affect only those cells in which they are expressed. Which group of early developmental genes are not cell autonomous?

How can transplantation and ablation be used to find out if a cell in the source of a developmental signal?

An Antennapedia (Antp) mutant in Drosophila has legs in place of antennae. This is caused by______ .

In Arabidopsis thaliana, a model organism in plant genetics, there are three classes of genes that control the development of floral structures: A, B, and C. Mutations of these genes cause organs to form in inappropriate places. What category of genes are they?

Homeotic genes in virtually all animals are said to show colinearity between the spatial arrangement of the tissues they act on as well as what other feature?

Molecules whose concentration and position in an embryo determine some aspect of development are called_________ .

Many mutations in the bithorax gene are known, such as postbithorax, contrabithorax and bithoriaxoid. Each mutation has a different effect on development of the reduced wing- like T3 appendage, the haltere. None of these mutations occurs in the coding sequence of bithorax, instead, where are these mutations and how do they effect development?

Genes that influence development in a manner that is independent of their paternal genotype are said to have ___________effect.