1. Intro to key concepts Flashcards
(14 cards)
What are the three main processes of development?
- Proliferation and Growth
- Differentiation
- Morphogenesis
These processes encompass the fundamental stages of how organisms develop from a single cell to complex structures.
What is the definition of developmental potential (potency)?
The ability of a cell to contribute to development and differentiate into specific cell types
Potency describes the range of cell types a stem cell can become.
What are the levels of potency?
- Totipotency
- Pluripotency
- Multipotency
- Unipotency
Totipotent cells can form all embryonic and extra-embryonic tissues, while potency decreases as development progresses.
What is the difference between specification and determination in cell commitment?
Specification is reversible; determination is irreversible
Specification allows cells to differentiate autonomously in a neutral environment, while determined cells follow their fate regardless of environmental signals.
What happens during the differentiation process?
Cells acquire specialized functions, cease dividing, and express specific genes while repressing others
Differentiation marks the final stage of cell commitment where cells take on distinct identities.
What is autonomous specification?
Cell fate determined by factors present within the cell itself
This type of specification is often seen in invertebrates and relies on maternal determinants.
How does conditional (regulative) specification work?
Cell fate is determined by interactions with the environment and signals from surrounding cells
This strategy allows for flexibility and compensation in cell fate, common in vertebrates.
What characterizes syncytial specification?
Involves nuclear divisions without cell membrane formation, creating a syncytium
This method is primarily observed in insects like Drosophila.
What role do morphogens play in development?
Morphogens create concentration gradients that provide positional information
These gradients help cells understand their location and fate during development.
Why is cell communication important in development?
Cells must communicate to trigger specific developmental decisions and ensure correct development
Proper signal reception and response are crucial for the formation of tissues and organs.
Fill in the blank: The process where cells acquire specific structural and molecular features is called _______.
Differentiation
Differentiation is the process that distinguishes one cell type from another.
True or False: Determination can be reversed.
False
Once a cell is determined, it cannot change its developmental fate, even in a non-neutral environment.
What is an example of autonomous specification?
Ascidian (Sea Squirt) Development
Edward Conklin’s experiments demonstrated how maternal determinants affect cell fate in sea squirts.
What is the significance of Bicoid and Nanos in Drosophila development?
They establish the anterior-posterior axis through opposing gradients
The ratio of these morphogens determines positional identity in the developing embryo.
