Zaidi: Principles of Development Flashcards
What controls development of organisms
Differential gene expression
Homologous proteins are functionally _____
Interchangeable
After genome becomes activated, cells divide and cohere to form a _______
Blastula
Blastula undergoes massive rearrangements to form ______
Gastrula
Ectoderm is precursor for
Nervous system and epidermis
Endoderm is precursor for
Gut, lung and liver
Mesoderm is precursor for
Muscles and connective tissue
What is it called when multiple organisms have several homologs of the same gene
Gene duplication
What proteins are most important for development
Gene regulatory proteins
Coding sequence vs non coding sequence in development
Coding sequences in DNA are similar in most organisms, but non coding sequences make one organism different from another–uniqueness
Cells fated to develop into a specialized cell type despite changes in environment
Determined
Cells that can change rapidly due to alterations in environment
Completely undetermined
Cells that have some attributes of a particular cell type but can change with environment
Committed
Position specific character of a cell is called
Positional value
Cells can become different due to
Assymetric division
Cells born the same can become different due to
Change in environment after birth
Most important environmental cues are
Signals from neighboring cells
Inductive signaling is
Induction of a different developmental program in select cells in a homogenous group leading to altered character
Morphogen is
A long range inductive signal that imposes a pattern on a field of cells
Exerts graded effects by forming gradients of different concentrations
Gradient can be formed in what two ways
Localized production of an inducer that diffuses away from its source
Localized production of an inhibitor that diffuses away and blocks the action of a uniformly distributed inducer
Combinatorial control
Response of a cell to a given signal may differ based on the presence of other signals (combinations create variety)
Cell memory
Effect of a given signal depends of previous experiences of the cell (which may have altered its chromatin, regulatory proteins, transcription and RNA)
Sequential induction
Different signals formed/secreted in a spatial and temporal manner
Ultimate result of inductive events is
Change in DNA transcription
Response to signals depends on
Spatial and temporal expression of different sets of genes
