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Flashcards in Ontogeny Deck (35):
1

What is ontogeny

Growth and development of an organism -the changes in its size and structure

2

Did Biogenetic Law grow in popularity or fall out of favour?

It fell out of favour

3

What was Biogenetic Law replaced by

Von Baer's Principles

4

What is Biogenetic Law

It states that ontogeny recapitulates phylogeny

5

What does ontogeny recapitulates phylogeny mean

That the development (ontogeny) of an organism expresses all intermediate forms of its ancestors throughout evolution (phylogeny)

6

What is another way of describing biogenetic law

It states that each developmental stage represents an adult form present in an organism's evolutionary history

7

What came first, biogenetics law or von baer's principles

Von Baer's Principles predated Biogenetics Law

8

What are the principles of Von Baer's Principles

In ontogeny; character states of higher taxa (kingdom, phylum & class) develop early. Character states of lower taxa (family, genus, species) develop later.

9

In Von Baer's Principles, early developmental stages resemble early/adult stages of an ancestor

early

10

What is peramorphosis

adding additional developmental stages compared to the amount the ancestor had

11

In peramorphosis, the juvenile form of the descendant resembles the ____ form of the ancestor

adult

12

What are the types of peramorphosis

Hypermorphosis, Acceleration, and Predisplacement

13

What is hypermorphosis

A type of peramorphosis where development stops later

14

what is acceleration

A type of peramorphosis where the rate of development is accelerated

15

What is predisplacement

A type of peramorphosis where growth starts earlier in development

16

Paedomorphosis

This is the retention of juvenile features in the adult stage of an organism

17

What are the three types of paedomorphosis

Progenesis, Neotony, Postdisplacement

18

What is Progenesis

A type of paedomorphosis where development stops earlier

19

What is neotony

A type of paedomorphosis where the rate of development is slowed

20

What is postdisplacement

A type of paedomorphosis where growth starts later in displacement

21

What is an example of a paedomorphic species

Human beings

22

What are hox genes

They are genes that code for transcription factors, which tell other genes when to turn on and off

23

Are hox genes highly conserved or do they vary alot among species

They are highly conserved

24

What happens if you manipulate hox genes

Death or severe abnormalities

25

What do the Hox patterning Genes control

Formation of body axis and bilateral symmetry

26

What is the homeobox that hox genes contain

a 180 bp region that is highly conserved and extremely important in development

27

Single hox genes underwent _____ duplication

tandem

28

Multiple hox genes are arranged in Hox _____

Clusters

29

How many hox clusters to protosomes and invertebrates have

1

30

How many hox clusters do jawless vertebrates have

2

31

How many hox clusters do humans have

4

32

How many hox clusters do teleosts have

7 or 8

33

What is subfunctionalization

The way hox genes have redundancy, so that their will be back ups. This way the organism is not affected

34

What is neofunctionalisation

If a good mutation arises, it leads to a new function or a new structure

35

What is heterochrony

a developmental change in the timing or rate of events, leading to changes in size and shape