Devpt Of Multicell Organisms 1 Flashcards
What does it mean for cells to have a memory?
They retain record of signals their ancestors received during embryonic development.
Ectoderm
Precursor of the nervous system and the epidermis
Endoderm
Precursor of gut, lung and liver
Mesoderm
Precursor of muscles and connective tissue
Gastrulation
Transformation of a hollow sphere of cells into a structure w/ a gut
What are the two classes of proteins most important for development?
Cell adhesion/ cell signaling proteins and Gene regulatory proteins
Where are the instructions for producing a multicellular animal contained?
In the non-coding regulatory DNA associated a/ each gene
In DNA, what serves as the biding sites for gene regulatory proteins?
Regulatory elements within the DNA; regulatory DNA defines the sequential program for development
What makes one organism different from another and provides uniqueness?
Non-coding sequences
When do cells make developmental decisions?
Long before they show any outward sign of differentiation
Define “determined”
Cells that are fated to develop into a specialized cell type despite changes in environment
Define “completely undetermined”
Cells that can change rapidly due to alterations in environment
Define “committed”
Cells that have some attributes of a particular cell type but can change with environment
What does it mean for cells to be regionally determined?
Before acquiring a particular fate, they express genes that are markers of their location. The position specific character of a cell is called positional value
What are the most important environmental cues?
Signals from neighboring cells
