Introduction Part 1 Flashcards
(28 cards)
most animals develop from a single cell, fertilized egg called
zygote
The study of animal development has traditionally been called ___________, after that phase of an organism
that exists between fertilization and birth.
embryology
most organisms never stop developing (3)
RBC, regenerate severed parts, metamorphosis
- the study of HOW an egg becomes an adult organism
- the process by which new members of a species are generated
- it is closely related to ontogeny
developmental biology
the course of an organism’s development from inception to adulthood
ontogeny
- it is the study of a PROCESS whereby a single cell (the fertilized egg) divides and selectively activates expression of genes to produce a complex organism composed of many cell types
developmental biology
the discipline that studied embryonic and other developmental processes
developmental biology
- observational biology
- experimental manipulations
embryology
- expands embryological studies using molecular techniques
- used genetic approaches to study model organisms
developmental biology
model organisms (9)
- Arabidopsis thaliana - Thale cress
- Drosophila melanogaster - Fruit fly
- Hydra vulgaris - Hydra
- Caenorhabditis elegans - Nematode worm or C. elegans
- Xenopus laevis - African clawed frog
- Brachydanio rerio - Zebrafish
- Gallus gallus - Chicken
- Mus musculus - Mouse
- stem cells of Homo sapiens
criteria for a model biological system (model organism) (6)
- easy to maintain
- operation size should be convenient
- inexpensive to maintain
- short life cycle
- can be genetically manipulated
- able to deliver economically important results
development accomplishes two objectives (2)
- it generates cellular diversity and order within each generation
- it ensures the continuity of life from one generation to the next
2 fundamental questions in developmental biology
- How does a fertilized egg become an adult body?
- How does that adult body produce yet another body?
Developmental Biology is defined by the questions asked: (7)
- Differentiation
- Morphogenesis
- Growth
- Reproduction
- Regeneration
- Evolution
- Environmental Integration
- is the process where a cell changes from one cell type to another
- process in which cells develop their specialized shaped and functions
cellular differentiation
- How do cells arising from a fertilized egg become different from one another?
- What goes on as an embryo develops from a single pluripotent cell into a complete organism?
differentiation
majority of development systems are
multicellular
generation of cellular diveristy
differentiation
The gradual increase in size or number of an animal or vegetable body over time.
growth
two types of growth (2)
- allometric growth
- isometric growth
- different growth rates of parts with the same organism
- change in shape during ontogeny (ratio between parts changes as the size increase)
- relatively common
- it possesses an enlarged major or threatening other males
- males with larger claws attract more female mates
allometric growth
- all components grow at the same rate
- no change in shape during ontogeny (ratio between parts does not change as the size increase)
- the shape is preserved
- relatively uncommon
isometric growth
early development of many organisms is influenced by ________
environmental cues
ectoderm can form (3)
- outer surface: epidermal cells of skins
- central nervous system: neuron of cells
- neural crest: pigment cells
