Development L 17 Notes Flashcards
What is developmental biology?
• Developmental Biology:
- Study of:
Growth of an organism from a fertilised egg to an adult organism
How that organism reproduces
How it repairs & replaces cells or tissues after injury or under normal homeostatic conditions.
Why is developmental biology important?
• Importance of Developmental Biology:
- Better undertstanding of underlying basis -> congenital birth defects.
- Dev. of more effective treatments for human diseases Eg. Regenerative medicine.
- Cannot understand evolution without understanding development
Selection acts upon phenotype
What does LECA stand for?
• LECA:
Last Eukaryotic Common Ancestor
Describe why Arabiopsis thaliana is used as a model organism / the benefits
• Arabidopsis thaliana (Thale Cress)
- Small
- Easy to grow
- Short generation
- Flowering plant
- Embryology
- Good imaging
- Genetics
- Sequenced genome
- Trasngenesis
- Agrobacterium -> Make transgenic plants
Describe why Dictyostelium discoidum is used as a model organism / the benefits
• Dictyostelium discoidum
- Chemotaxis
-> Moves towards signals sent by other molecules (CAMP) to aggregate & form
fruiting body under stressful conditions.
- Genetics
- Multicellularity
-> Single amoeba cell which can aggregate to form fruiting body understressful
conditions.
-> Low food conditions -> form spores.
- Good imaging
- Sequenced genome
- Transgenesis
- Social behaviour
- Cheating & altruism
- Chemotaxis toward cAMPDescribe why Hydra are used as model organisms / the benefits
• Hydra - Metazoans -> Animals - Radial symmetry - Diploblastic Ectoderm & Endoderm - Small - Easy to grow - Sexual & Asexual reproduction - High regenerative capacity
Describe why Planaria are used as model organisms / the benefits
• Planaria: - Bilateral symmetry - Triploblastic Ectoderm, mesoderm & endoderm - RNAi knockdown technology - Adult stem cells - Sexual & Asexual reproduction - High regenerative capacity
Describe why Caenorhabditis elegans are used as model organisms / the benefits
• Caenorhabditis elegans - Short Generation time - Sexual & self-reproduction - Males & hermaphrodites Hemaphrodites produce eggs & sperm --> Can self-fertilise & perform genetic cross -> One organism. - Genetics - RNAi knockdown technology - Sequenced genome - Study -> Aging - Lineage of all cells known - Imaging - Provided most knowledge -> Cell death
Describe why Ciona intestinalis: (Sea urchins, starfish, sea cucumbers) (Amphipod crustacean) are used as model organisms / the benefits
• Ciona intestinalis:
- Basal chordate
- Transgenesis
- Genetics
- Sequenced genome
- Imaging
- Develop notochord in dev. after 1 day
Describe why Brachiostoma Ianceolatum are used as model organisms / the benefits
• Danio rerio: (Zebrafish)
- Genetics
- Sequenced genome
- Transgenesis
- Imaging
- Transparent embryos
- Regeneration capacity
- External development
- Vertebrate
Describe why Xenopus (Frogs) are used as model organisms / the benefits
Xenopus:
- Embryos produced -> Large nos
- External development
- Rapid development
- Cell division
- Transparent tadpoles
- Easy -> production of explants & transplants
Can cut embryos -> albino & pigmented. Attach different halves -> rapid effective healing -> produce half albino & half pigmented individuals.
- Generation of transgenic embryos
- Promoter elements / regulatory proteins of other organisms
-> Mouse elastase-GFP transgenic embryo -> insertion of other organism
-> Mouse Tie2-GFP transgenic tadpole -> Circulatory system
- Rapid, effective wound healing
Imaging
- Regeneration of appendages -> tadpoles
- Tetrapods
Describe why Gallus gallus (Chicks) are used as model organisms / the benefits
• Gallus gallus (Chick)
- Transplantation experiments
- Sequenced genomes
- Overexpression & knockdown experiments
- Imaging
- Development of embryo outside cell
Describe why Mus musculus: (Mice) are used as model organisms / the benefits
• Mus musculus: (Mouse)
- Mammal
- Strong genetics
- Sequenced genome
- Mammal
- Pluripotent embryonic stem cells
- Short generation time
Describe why Homo sapiens are used as model organisms / the benefits
• Homo sapiens
- Genetics
- Sequenced genome
- Mammal
- Induced pluripotent stem cells
- Large population
- Large no. mutated genes
Describe the benefits of Developmental Biology Studies:
• Developmental Biology studies:
- Rich source of information -> variety of model organisms
- Enable better understanding -> Biodiversity
-> Congenital disease
- Investigation -> mechanisms leading to tissue formation , repair & regeneration
Enable clinical interventions
-> improving healing, transplant & regeneration of tissues following injury /
aging process.
