Evo-Devo (2/26) Flashcards
Blastocyst
structure formed in the early development of mammals and is what implants itself within the walls of the uterus
Three Germ Layers for ALL Vertebrate Animals
- ) Ectoderm: forms skin cells, brain cells, hair, tooth enamel, nails
- ) Mesoderm: forms skeletal muscle, organs, red blood cells
- ) Endoderm: forms lungs, glands, inner lining of the gut
What does “pluripotent” mean? (Stem Cells)
the cell is mature and is capable of giving rise to a variety of different cell types;
this is why stem cell research holds so much promise for th treatment of certain injuries and diseases
Which developmental stage is useful for embryonic stem cell research?
Blastocyst stage!
What Are Homeobox (Hox) Genes?
Homeobox genes are a large family of genes that direct the formation of body parts during early embryonic development
What do Hox Genes do?
they encode proteins (transcription factors) that regulate gene expression in multicellular organisms
What can be said about DNA sequences for Hox Genes?
they are similar among different species (thing the mouse eyeball gene that was injected in to the fly)
- genes active in the head lie at one end and those in the tail at the other
What do the Hox Gene Transplantation and Knockout Experiments tell us about the role of Hox Genes?
Hox genes have similar functions even across many different organisms
- the exact same Hox genes occur in ALL animals
How do Hox genes vary between different organisms?
differences involve duplications and deletions
- varying number of HOX gene sets between organisms (flies have 1 set of 8 while humans have 4 sets)
Vestigal Structures
degenerate or underdeveloped; reduced in size and function by natural selection as no longer required
Atavistic Features
an evolutionary “throwback”, only occurs occasionally within a species
