EvoDevo Ch. 1-3 Flashcards Preview

Biology 112 > EvoDevo Ch. 1-3 > Flashcards

Flashcards in EvoDevo Ch. 1-3 Deck (39):
1

Animal form is the product of what two processes and how are these processes related?

development from an egg and evolution from ancestors

development is the process in which an egg eventually grows into adult form and evolution of form occurs through changes in development

2

Theory of punctuated equilibrium

Idea that evolution is marked by long periods of stasis and interrupted by brief intervals of rapid change

3

"Evo devo" is short for what?

evolutionary development

4

What is the task of the "master" genes

control the formation and patterning of bodies and body parts

5

How did the discovery of developmental geneses change the way we think about animal relationships?

We can now see how different species formed and how they're related, even if they don't appear to be on the outside

6

Tool Kit Paradox

Paradox of great genetic similarity among diverse species

The development of a species depends on genes being turned on or off at certain times 

where in the genome the "smoking guns" for evolution in form are found

 

7

First basic theme of animal design

related animals are made up of similar parts

8

Second basic theme of animal design

individual animals are made up of numbers of the same kinds of parts (like building blocks)

9

Modular architecture of animals

bodies are composed of similar, repeating parts

10

Bateson's contribution to our understanding of animal form

He noted that animals differ in the number and kind of repeating parts

11

Homologs (and examples)

Same structure modified in different ways in each species

ex. forelimbs of salamandars, mice, and our arms

12

Serial homologs and example

structures that arose as a repeated series and have become differentiated to varying degrees in different animals

ex. hindlimbs, our legs, hind legs of four-legged vertebrates (with respect to each other)

13

Symmetry of animal form

most species have an axis of symmetry.  This gives us clues as to how the animal was built

14

Polarity of animal form

head to tail

top to bottom (back and front in humans)

near to far from the body

15

teratogens

chemicals that cause monster-like mutations during embryonic development

16

Spemann's experiment with newt embryos.  Significance of results?

He tied off a newt embryo first horizontal to the furrow and then perpendicular to it.  It showed that the dorsal lip of the blastopore is critical for the organization of the embryo

17

Function of Spemann's "organizer"

It organizes the dorsal part of the embryo into neural structures and could initiate the development of another embryonic axis

18

Function of the Zone of Polarizing Activity (ZPA) in the chick limb

It creates a mirror image polarity in the digits of the chick wing

19

Morphogenesis

property of influencing the formation of pattern

20

some developmental variants in humans

extra ribs, extra nipples, extra fingers

21

Polydactyly

extra body parts

22

What do homeotic mutants of fruit flies tell about developmental process?

A single gene can cause serial homologs

23

How does DNA connect all six kingdoms of organisms?

It's the basis of heredity for all 6 kingdoms

24

How are specialized cells within a single animal different from each other?

They make different proteins

25

Relationship between chromosomes and DNA

chromosomes are made up of DNA

26

In what way does DNA encode information?

sequence of base pairs.  These sequences determine which proteins will be made

27

Transcription

Translation

Transcription - RNA being made from DNA

Translation - RNA sequences code for proteins

28

How does the presence of lactose modify gene expression in E. coli?

When lactose is present, the usual gene repressor falls off the switch and turns the gene on to begin making the enzyme

29

Homeobox

Homeodomain

Function

Homeobox - 180 base-pair sequence in homeotic genes 

Homeodomain - the corresponding protein domain it encodes

The homeodomain controls gene switches, so it affects the formation and identity of whole structures

30

Homeotic (Hox) genes 

function

Homeotic genes with homeoboxes are Hox genes.  They regulate development

31

Hox genes were originally studies in fruit flies.  What other organisms have Hox genes?

almost all animals

32

What is the function of the Pax-6 gene in flies, mice, and humans?

 

eye formation

33

Function of Dll gene in animals

limb formation

34

Function of tinman gene

it's required in order to make the fly heart

35

How are the Pax-6, Dll, and tinman similar to each other?

They are all DNA-binding proteins.  They all regulate on/off switches of genes

36

Transcription factor

proteins that bind to DNA and directly turn gene transcription on or off

37

Signaling pathway

cells communicating via proteins

38

Kinds of genes in genetic tool kit

Hox proteins, Pax-6, tinman, Distal-less, cell-type regualtions, hedgehog, hormones, etc

39

What are the function of the hedgehog genes and how do they relate to polydactyly, cyclopia, fetal alcohol syndrome, and cancer in humans?

limb bud (ZPA)

polydactyly is caused by a mutation that affects sonci hedgehog expression during development.  

Cyclopia is an inhibitor of sonic hedgehog signaling pathway.  Alchol can have the same effect as this.  

Mutations in the sonic hedgehog can cause tumors