Fundamental Principles Flashcards
1
Q
draw the relationship between cell communication, genetic programming and cell behaviour
A
2
Q
- Epigenesis
- preformation
- cell theory
- germ plasm determinants theory
- mosaic development (+ evidence)
- induction theory (+ evidence)
A
- organisms develop progressively through the generation of new strucures
- organisms develop from minature versions of themselves. Development involves the expansion of existing structures
- all organisms are comprised of one or more cells. The cell is a basic unit of structure, function and organisation. All cells arise from pre-existing cells
- offspring inherit their characteristics from germ cells rather than somatic cells. Germ cells carry info that can be passed on through generations. Somatic cells are unable to pass on info to the next generation therefore characteristics acquired by the body during a lifetime can’t be transmitted to the germline.
- cells are prespecified. the killing of one blastomere at the 2 cell stage lead to the formation of only half a tadpole
- cells must be specified by an inductive signal. separation of blastomeres at the 2 cell stage lead to the development of 2 tadpoles.
3
Q
- give 2 types of cell division
- give 2 types of cell adhesion
- give 2 types of cell shape
- give 2 other examples of changes in cell behaviour
A
- symmetrical or asymmetrical
- condensation or dispersal
- epithelial or mesenchymal
- migration and cell death.
4
Q
- endocrine signalling
- paracrine signalling
- autocrine/amacrine signalling
- juxtactrine signalling
- through which structures may cell communication also occur?
- what is required for a cell to be competent to signalling?
A
- involves hormones (irrelevant to embryonic development)
- secreted signalling molecules act on neighbouring cells over a short or long distance
- signalling molecules act on the cell that produces the signal, either externally or internally
- contact dependent signalling between 2 neighbouring cells
- gap junctions
- permissive environment; receptor; transduction components
5
Q
- what does gene expression influence?
- name 4 levels at which gene expression is controlled
A
- a cell’s characteristics
- mRNA production; mRNA processing; protein production; protein activity.
6
Q
- What is pattern formation?
- What does pattern formation ensure?
- how do the germ layers confer pattern?
- in what order do the 3 axes develop?
- what must positional information translate into?
A
- the temporal and spacial organisation of cells
- ensures tha well ordered structures develop within an organism
- they distinguish between regions which give rise to specific tissue types
- 1st=AP; 2nd=LR; 3rd=DV
- differential gene expression
7
Q
- what is morphogenesis?
- what does morphogenesis involve?
- Give 4 methods of how morphogenesis occurs.
A
- shape creation
- reorganisation of cells to adopt highly organised shapes
- cell migration
cell adhesion
cell shape
cell death
8
Q
- what is cell differentiation governed by?
- what does it involve?
- Give the 4 stages of cell differentiation.
A
- differential gene expression
- loss of pluripotency over time
- 1) specification
2) determination
3) differentiation
4) maturation
9
Q
- what is growth?
- the rate of growth of a particular tissue depends upon what
- give 3 methods of growth
A
- an increase in mass or size
- age and the tissue type
- proliferation; cell enlargement; accretion (enlargement of the matrix)
10
Q
Why are animal models useful in the study of developmental biology?
A
early embryonic development (particularly of vertebrates) shares similar features therefore information of development can be applied from one organism to another.
11
Q
- What is observational biology used to study?
- How is labelling with dye used?
- give 3 examples of genetic labelling
A
- cell linage and fate mapping
- a cell is labelled with a dye, and structures derived from the labelled cell will also be labelled
- electroporation uses an electric field to change the permeability of the membrane so that foreign genes can be introduced into the cell
- GFP
- Rainbow organisms can be created by labelling individual cells with different proportions of R G & B GFP varients so that each cell is a different colour. Offspring of these cells will too be labelled with the colour.
- electroporation uses an electric field to change the permeability of the membrane so that foreign genes can be introduced into the cell
12
Q
- what is tissue manipulation used to study?
- give 2 examples of tissue manipulation
A
- inductive function of cells/proteins
- tissue ablation, graft, transplantation
transplantation of a protein soaked bead.
13
Q
Give 3 methods used to study gene expression
A
- In situ Hybridisation
- high throughput analysis using microarrays (creation of cDNA from RNA in the cell; this cDNA is used as a probe of DNA libraries)
- reporter lines (a reporter gene is attatched to the promoter region of the gene of interest so that it is expressed with or instead of the gene of interest)
14
Q
give a method that can be used to study protein distribution within a cell/tissue
A
immunohistochemistry.
15
Q
- what is forward genetics used for?
- outline the basic steps of forward genetics
- what is reverse genetics used for
- outline the steps of creating a knockout organism
A
- to identify the gene whose mutation gives a particular phenotype
- generation of random mutants; subsequent crossbreeding; isolation of individuals with interesting abberant phenotypes
- to identify the phenotype of genes from its mutant
- desired mutant gene is inserted into a vector
- vector is introduced into cultured ES cells
- cells that have been transformed are isolated
- transformed cells are inserted into an embryo to produce a chimera
- chimeras are bred with wild type organisms to produce heterozygous offspring
- F1 progeny are crossbred. 25% of offspring will be homozygous for mutant.
- desired mutant gene is inserted into a vector
