Phylogeny and Systematics - PowerPoint PPT Presentation

Loading...

PPT – Phylogeny and Systematics PowerPoint presentation | free to view - id: 4c6661-YWMwY



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Phylogeny and Systematics

Description:

Phylogeny and Systematics D.5 Chapter 15 D.5.1 Outline the value of classifying organisms If a new organism is discovered, its characteristics can be compared with ... – PowerPoint PPT presentation

Number of Views:140
Avg rating:3.0/5.0
Slides: 19
Provided by: Southridg76
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Phylogeny and Systematics


1
Phylogeny and Systematics
  • D.5
  • Chapter 15

2
D.5.1 Outline the value of classifying organisms
  • If a new organism is discovered, its
    characteristics can be compared with existing
    organisms.
  • Similarities allow it to be linked with other
    organisms
  • Organization of data
  • assists in identifying organisms
  • suggests evolutionary links
  • allows prediction of characteristics shared by
    members of a group.

3
D.5.2
  • Explain the biochemical evidence provided by the
    universality of DNA and protein structures for
    the common ancestry of living organisms
  • There are remarkable similarities between living
    organisms in their biochemistry

4
D.5.2
  • There are remarkable similarities between living
    organisms in their biochemistry which suggest a
    common ancestor
  • All use
  • DNA or RNA as genetic material
  • universal genetic code
  • same 20 amino acids in proteins
  • Left (not right) handed amino acids
  • Ex some proteins created in one organism
    (insulin in bacteria) can be used in other
    organisms (for therapy in humans)

5
D.5.3 Explain how variations in specific
molecules can indicate phylogeny
  • Phylogeny Evolutionary history of a species or
    group of related species
  • Look at
  • Proteins close match in amino acid sequence in
    different species indicated a common ancestor
    (hemoglobin, cytochrome c, chlorophyll)
  • DNA differences in base sequence
  • More useful than protein for comparison because
    protein only reflects a small part of DNA

6
(No Transcript)
7
D.5.4 Discuss how biochemical variations can be
used as an evolutionary clock
  • The more similar the DNA or protein is the more
    closely related the organisms
  • Differences in protein sequence accumulates
    steadily and gradually over time due to mutations
    which occur generation to generation in a species
  • Mutations occur at various rates so the
    information is just an estimation of time. The
    biochemical data is compared to fossil evidence
    and radioisotope dating.

8
D.5.4 Discuss how biochemical variations can be
used as an evolutionary clock
  • Compare DNA of different species
  • Count the number of base pairs that dont match
  • The more differences more time between split
    (less related)
  • DNA Hybridization fuse one strand from species A
    and a homologous strand from species B
  • Fuse match
  • Repel difference in DNA sequence

9
(No Transcript)
10
D.5.5 Define clade and cladistics
  • Cladistics system of classification which groups
    taxa together according to the characteristics
    which have recently evolved (natural
    classification)
  • Clade groups of most recent common ancestor of
    the group and its descendents (can be one species
    or several species)

11
(No Transcript)
12
D.5.6 Distinguish between analogous and
homologous structures
  • Homologous structures
  • Likeness in structure from having a common
    ancestor
  • Ex fingers on mammals, eyes on verts inverts
  • Analogous structures
  • Structures serve similar function but NOT
    resulting from a common ancestor
  • Ex wings on insects birds, fins on aquatic
    organisms

13
D.5.7 Outline the methods used to construct
cladograms and the conclusions that can be drawn
from them
  • Cladograms show evolutionary relationships
    between organisms
  • Method
  • Make a list of organisms
  • List characteristics of each organism
  • Choose one primitive characteristic common to all
    organisms
  • Complete a comparative table of the organisms
  • Build a cladogram from the table

14
D.5.7 Outline the methods used to construct
cladograms and the conclusions that can be drawn
from them
  • The first branch from the bottom belonging to the
    organism with fewest derived traits
  • Most derived traits at the top of the last branch
  • Each new line is a clade

15
(No Transcript)
16
D.5.8 Construct a simple cladogram
  • Morphological or biochemical data can be used
  • See Island Biogeography Lab for practice

17
D.5.9 Analyze cladograms in terms of phylogenic
relationships
  • Common ancestry
  • More evolved organisms based on more evolved
    characteristics
  • More nodes between organisms, the less related
    they are
  • Closer the lines more related

18
D.5.10 Discuss the relationship between
cladograms and the classification of organisms
  • Cladistics uses biochemical data (versus
    morphological data used in Linnean system) to
    classify organisms
  • Classification system center around
  • Shared derived characteristics
  • Parsimony least complicated explanation for a
    phenomenon
About PowerShow.com