EvoDevo Ch. 1-3

Question 1

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

Answer 1

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

Question 2

Theory of punctuated equilibrium

Answer 2

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

Question 3

“Evo devo” is short for what?

Answer 3

evolutionary development

Question 4

What is the task of the “master” genes

Answer 4

control the formation and patterning of bodies and body parts

Question 5

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

Answer 5

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

Question 6

Tool Kit Paradox

Answer 6

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

Question 7

First basic theme of animal design

Answer 7

related animals are made up of similar parts

Question 8

Second basic theme of animal design

Answer 8

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

Question 9

Modular architecture of animals

Answer 9

bodies are composed of similar, repeating parts

Question 10

Bateson’s contribution to our understanding of animal form

Answer 10

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

Question 11

Homologs (and examples)

Answer 11

Same structure modified in different ways in each species

ex. forelimbs of salamandars, mice, and our arms

Question 12

Serial homologs and example

Answer 12

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)

Question 13

Symmetry of animal form

Answer 13

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

Question 14

Polarity of animal form

Answer 14

head to tail

top to bottom (back and front in humans)

near to far from the body

Question 15

teratogens

Answer 15

chemicals that cause monster-like mutations during embryonic development

Question 16

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

Answer 16

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

Question 17

Function of Spemann’s “organizer”

Answer 17

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

Question 18

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

Answer 18

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

Question 19

Morphogenesis

Answer 19

property of influencing the formation of pattern

Question 20

some developmental variants in humans

Answer 20

extra ribs, extra nipples, extra fingers

Question 21

Polydactyly

Answer 21

extra body parts

Question 22

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

Answer 22

A single gene can cause serial homologs

Question 23

How does DNA connect all six kingdoms of organisms?

Answer 23

It’s the basis of heredity for all 6 kingdoms

Question 24

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

Answer 24

They make different proteins

Question 25

Relationship between chromosomes and DNA

Answer 25

chromosomes are made up of DNA

Question 26

In what way does DNA encode information?

Answer 26

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

Question 27

Transcription Translation

Answer 27

Transcription - RNA being made from DNA Translation - RNA sequences code for proteins

Question 28

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

Answer 28

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

Question 29

Homeobox Homeodomain Function

Answer 29

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

Question 30

Homeotic (Hox) genes function

Answer 30

Homeotic genes with homeoboxes are Hox genes. They regulate development

Question 31

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

Answer 31

almost all animals

Question 32

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

Answer 32

eye formation

Question 33

Function of Dll gene in animals

Answer 33

limb formation

Question 34

Function of tinman gene

Answer 34

it's required in order to make the fly heart

Question 35

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

Answer 35

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

Question 36

Transcription factor

Answer 36

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

Question 37

Signaling pathway

Answer 37

cells communicating via proteins

Question 38

Kinds of genes in genetic tool kit

Answer 38

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

Question 39

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

Answer 39

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