EVO DEVO

Question 1

Mendelian inheritance

Answer 1

helpful in understanding of inheritance of traits, alleles, gene

deceptive - suggests that this is the most common way traits are created genetically, not complex, dominant/recessive

Question 2

complex inheritance

Answer 2

many traits seem to be controlled by more than 1 gene or linked/inherited together

continuous - phenotypes are slight variations along a continuum

not all mutations are completely random

Question 3

Embryology

Answer 3

the study of the differentiation of a single-celled fertilized egg into a complex multicellular organism

embryo development is remarkably similar across all chordates, in the earliest stages of development (ex: all start out with gill slits and tails)

Question 4

Evolutionary developmental biology

Answer 4

discovery of genes which regulate embryonic development in eukaryote

link evolution to embryo

Question 5

Homeobox genes

Question 6

Fate Map

Answer 6

newly formed single cell (zygote) able to detect where is the center of the cell and assign cardinal points to corners of the cell, that helps map the rest of development (where things go)

Question 7

The rest of the steps of the fate map

Answer 7

axes of zygote are subdivided into more lat and longitudinal lines, keeps dividing within zygote

each new square given a unique identity and gets more specific and told what to grow

Question 8

The growth stage

Answer 8

grows inward and outward
growth start and stop at specific regions on the geomap

detail genes start which differentiate traits even more

Question 9

Deep homology

Answer 9

many genes shared across all eukaryotes must have evolved in the first eukaryote

most important genes evolved very early in eukaryotes, share the exact same gene regions regulating development (homeobox genes)

Question 10

Homeobox genes

Answer 10

are how we can share much of our genomes with other eukaryotes but look very different

even for eye, share many of the same genes for building

Question 11

What really makes a phenotype

Answer 11

many of the phenotypes we once thought were linked to a single gene

more a product of homeobox or detail genes growth turning on and off

new phenotypes arise when mutations occur that modify gene regulation (when on and off and where on the geomap), not a mutation in a single gene

zebras have the same detail gene but different points they turn on and off or where on the geomap

Question 12

Examples: Melanism, mimicry,

Answer 12

if a few genes control wings or melanism, higher chance these will be mutated over time

if melanism is turned on for entire organism instead of specific region of geomap, change in phenotype from simple mutation

This is how they have similar wing patterns, and if mimicry is advantageous, natural selection will preserve it in both species

Question 13

Redundant genes

Answer 13

key discovery in EVO DEVO: when a gene is not longer needed for its original purpose, can easily be repurposed into something functionally similar by evolution

ex: gills and wings
very similar in structure, very few changes needed to repurpose gills to wings
(homeobox genes code for gills, modified)

Question 14

Increasing Complexity in genes

Answer 14

increasing trait complexity (more homeobox genes) in newer species, despite full genome not always getting bigger

because of homeobox duplication

when you have extra developmental genes, thy can be repurposed for other functions like limbs or organs