Warm ­ Up: Escherichia coli
Escherichia coli (pron.: commonly abbreviated E. coli) is a Gram­negative, rod­
shaped bacterium that is commonly found in the lower intestine of warm­blooded organisms (endotherms). Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls due to food contamination. The harmless strains are part of the normal flora of the gut, and can benefit their hosts by producing vitamin K2, and by preventing the establishment of pathogenic bacteria within the intestine.
E. coli and related bacteria constitute about 0.1% of gut flora, and fecal–oral transmission is the major route through which pathogenic strains of the bacterium cause disease. Cells are able to survive outside the body for a limited amount of time, which makes them ideal indicator organisms to test environmental samples for fecal contamination. The bacterium can also be grown easily and inexpensively in a laboratory setting, and has been intensively investigated for over 60 years. E. coli is the most widely studied prokaryotic model organism, and an important species in the fields of biotechnology and microbiology, where it has served as the host organism for the majority of work with recombinant DNA.
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AP Biology
1. Warm ­ Up 5 2. Review Lab/Answer Questions/Discuss Test 15
3. Finish Chapter 25 Notes 10
4. Chapter 26 Notes 25
5. Work Time:
• Continue Comparing DNA Sequences to Understand Evolutionary Relationships with BLAST
• Week Assignments
• Study Guide Announcements
Due Friday, March 29, 2013: Week 8 Spring Assignments, BLAST Lab, and Study Guide
Review session Wednesday, March 24 at 7:50 AM in room 312.
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BLAST Lab
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Review Lab
1. What do the branches show? 2. Can the same trait evolve more than once? Is this likely?
3. Name four characters possessed by mammals.
Answer questions in the lab. Please answer these questions on separate pieces of paper in full sentences. Let's review the questions. 4
BLAST Lab Questions ­ Part 1
The Investigation 5
BLAST Lab Questions ­ Part 1
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BLAST Lab Questions ­ Part 2 7
BLAST Lab Questions ­ Part 2 1. What species in the BLAST result has the most similar gene sequence to the gene of interest?
2. Where is that species located on your cladogram?
3. How similar is that gene sequence?
4. What species has the next most similar gene sequence to the gene of interest?
5. What other data could be collected from the fossil specimen to help properly identify its evolutionary history?
Based on what you have learned from the sequence analysis and what you know from the structure, decide where the new fossil species belongs on the cladogram with the other organisms. Redraw the cladogram you created before.
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Chapter 25 Notes
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Chapter 25 Notes
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Chapter 25 Notes
Chapter 25 Notes
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Chapter 25 Notes
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Chapter 25 Notes
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Chapter 25 Notes
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Chapter 25 Notes
III. Systemacs : Tracing Phylogeny
a.
Taxonomy – K, P, C, O, F, G, S
i.
________________________‐ genus and specific epithet (refers to species)
Example: Homo sapiens
ii.
Kingdoms are arranged into _________________ ex) ____________
iii. Pneumonic: ________________________________________________ b.
c.
Sorng Homology from Analogy
i.
________________ – Likeness aributed to shared ancestry ii.
_________________ – Likeness due to similar ________________ roles
Modern phylogenec systemacs is based on i.
_________________________
A ___________________ is a tree constructed from a series of dichotomies
ii. A ______________ is made up of ancestral species and ________ of its descendent species (Figure 25.9)
iii. The forelimbs of mammals are ________________________ (bat’s wing, whale’s flipper, arm of a human).
*These are the significant ones in construcng phylogenec tree
iv. The wing of a bat and those of birds are _________________ since they arose independently .
v.
_____________________ data helps in forming cladograms
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Chapter 25 Notes
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Chapter 26 Notes: Early Earth and the Origin of Life
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Bacteria fossils of ancient bacteria foun din amber
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Fossilized embryos 22
Cambrian Explosion 23
Louis Pasteur 24
Miller‐Urey Experiment 25
Chapter 26 Notes: Early Earth and the Origin of Life
I.
Origin of Life
a. Major Episodes‐
i.
3500 mya Oldest _________________ Fossils
ii. 2700 mya ____________ Present in Atmosphere from Photosynthec Bacteria
iii. 2100 mya Oldest Eukaryoc Fossils
iv. 700 mya
Oldest _____________ Fossils
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Chapter 26 Notes: Early Earth and the Origin of Life
b. Possible Sequence of Events
i.
____________ synthesis of amino acids and nucleodes
ii. Monomersà____________________ (proteins and nucleic acids)
iii. The origin of self – _______________ molecules. RNA may have been an early self – replicator.
iv. Packaging of all these molecules into ______________ ‐ organisms that maintain internal chemistry that differs from the outside environment.
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Chapter 26 Notes: Early Earth and the Origin of Life
c. 1953‐ Miller and Urey Experiment
i. Created prehistoric Earth condions‐ Low oxygen gas, lots of lightning, volcanic acvity, lots of methane gas, ammonia, water, H2 and UV rays à
_______________, Sugars, Lipids, and Nucleodes.
d. Alternave Views
i.
_____________________ ‐ Organic maer came to Earth from space
ii. Life began on sea floor in ________________________ instead of shallow puddles
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Chapter 26 Notes: Early Earth and the Origin of Life
II. The Kingdoms of Life
a. Monera‐ Unicellular __________________________
i.
Ex) ________________________
b. Prosta‐ Unicellular or Mulcellular Eukaryotes
i.
Ex) _________________________
c. Plantae‐ Mulcellular, Eukaryoc, ____________________________
i.
Ex) __________________________
d. Fungi‐ Mulcelluar, Eukaryoc, Heterotrophs with _____________________
i.
Ex) __________________________
e. Animalia‐ Mulcellular, Eukaryoc, Heterotrophs without Cell Walls
i.
Ex) __________________________
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Review 32
Work Time • Continue Comparing DNA Sequences to Understand Evolutionary Relationships with BLAST
• Week Assignments
• Study Guide 33
Exit Questions: Define shared derived characteristic
Reminders
Due Friday, March 29, 2013: Week 8 Spring Assignments, BLAST Lab, and Study Guide
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