Basic principles and techniques Flashcards
What is tissue homeostasis?
Maintenance of the structure and function of organs in the body through the control of cell division and cell death via negative feedback, and through repair mechanisms operated by stem cells
Excess of stem cell renewal leads to what?
Hyperplasia and or tumerigenesis
Depeletion of stem cells may lead to what?
Tissue degeneration/ tissue aging
What is pattern formation?
The process by which cells are organised in space and time to produce a well-ordered structure within the embryo
What is morphogenesis?
Cell and tissue movement and changes in cell behaviour that give the developing organ its shape
What factors are important for cell movement and reorganisation?
Cell adhesion
Cell migration
Cell death
Cell shape
What is cell differentiation?
The process where cells become different to each other and acquire specialised properties
Governed by changes in gene expression
What is growth and what are its properties?
Growth in mass or size
Continuous process eg embryonic to fetal to post natal etc
Growth rate varies depending on age and the organ
Cell proliferation, cell enlargement and accretion
What is the funnel model and who made it?
hypothesis that the most conserved stage of development (the phylotypic period) occurs at the beginning of embryogenesis, with increasing divergence as development progresses
Haeckel
What is the hourglass model and who made it?
the idea that early embryos of different species display divergent forms but their morphologies converge in the middle of development, followed by a period of increasing divergence.
Von Baer
Which methods could you use to establish where a gene is expressed?
In situ hybridisation
Reporter lines
High throughput analyses eg microarray and RNAseq
What could you use to investigate if a protein is expressed at the same time as a gene
Western blot
Immunohistochemistry
Which methods could you use to investigate the distribution of proteins?
Immuno detection eg immuno histochemistry and immuno fluorescence
What could you do to investigate if a gene is essential for development?
gain of function and loss of function
What is a loss of function mutation?
mutation in a gene that disrupts the expression or the function of the protein product encoded by the mutated gene
What is a gain of function mutation?
mutation in a gene that confers a gain in the activity of the protein product encoded by the mutated gene
What is forward genetics?
seeks to identify a gene whose mutation caused a
particular phenotype
What is reverse genetics?
seeks to characterize the phenotype of particular
mutated gene.
Which model organisms can forward genetics be done in?
C elegans, drosophila, zebrafish and mouse
Which model organisms can reverse genetics be done in?
Mice
What methods could you use to demonstrate an inductive function?
Tissue ablation, graft or transplantation
Bead/cell implantation
