Author Archives: Stephen
Evolution (Core)
Ecuador Hummingbirds
Start with this reading on Evolution and Darwin: https://www.box.net/shared/6dx95t6ma6 and then watch this video of evolutionary researchers in action in Ecuador.
In the clip below, is Ross using the correct language when he describes the theory and evidence for evolution?
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Here is the class presentation
And the Essential Biology notes can be found here: https://www.box.net/shared/550sxdbx82
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There are many sources of interactives and animations on Evolution on the internet. Here are a few:
PBS Evolution has lots of high-quality activities and videos
BiologyInMotion has a very clear population evolution interactive
The Exploring Evolution weblab has examples of homologous structures and fossil evidence
MMHE has a pesticide resistance tutorial
And there are some good peppered moth simulations here and here
As always, sumanas has a great resource – this time on antibiotic resistance
And John Kyrk has a truly awesome timeline of the evolution of life
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Darwin resources:
Attenborough on Darwin: The Tree Of Life
Dawkins Darwin Lectures from OU/BBC
And of course, all of Darwin’s works are available online from darwin-online.org
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And here’s Dawkins on the evolution of the eye:
Classification
Grade 11 are starting out the course with a short “Nature of Biology” unit, made up of Statistical Analysis (and some practice with data), Classification, Evolution and a little introduction to ToK in Biology. Grade 12 are also looking at Classification at the moment, as part of the Ecology, Evolution and Conservation unit.
Here is the class presentation:
Download as pdf here: 5.5 Classification
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Work through this Essential Biology 5.5 Classification as you go through the presentation.
There are some activities you can download here:
- Shark ID Guide at Queensland
Invertebrate phyla cards and dichotomous key
Paired groups key-making activity: Spiders vs Beetles
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And here are the Click4Biology notes
There is also a great Environmental Science course online here: The Habitable Planet
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Have fun!
Inside Nature’s Giants
Channel 4’s fantastic series has just ended in the UK (I’m back for a holiday), and I can’t wait for the DVD. This is the kind of natural history quality that the BBC normally has a monopoly on, but C4 have presented something outstanding here.
Fin Whale Dissection
Over the four episodes, Mark Evans presents dissections of four giants of the animal world: elephant, whale, crocodile and giraffe. On hand is the expert anatomist Joy Reidenberg, who does a great job of taking apart and explaining their findings. Richard Dawkins takes the opportunity to point out some of the wonders of evolution in the animals, using anatomical and computer-graphic explanations. It’s great.
Embedded below are part one and part two of the second episode: fin whale. Rather than dissect at the Royal Veterinary College as normal, their challenge was to dissect this whale which washed up on the coast of Ireland before it exploded with decomposition.
If you can get 4onDemand, all four episodes are available online for a month. They are not available for download, but to really get the full effect, you need a high-quality image – so fingers crossed for the DVD!
For now, visit the official website for some clips and animal autopsy games.
Moonwalking: 40 Years On
Apollo 11 NASA page
Moonwalking is all over the news at the moment, as we approach the fortieth anniversary of the first humans to walk on the surface of the moon in the Apollo 11 mission.
On the 16th July 1969, Neil Armstrong, Buzz Aldrin and Michael Collins blasted off for the moon. On the 20th, Armstrong and Aldrin set foot on the surface of the moon: a massive landmark in science, adventure and international TV broadcasting. You’ve got to feel a bit sorry for Collins though – driving all that way just to stay in the car.
Here is the short news clip and the famous “one small step” line:
The NASA website has loads of great resources about the moon landing and the Apollo missions, so head on over there and check them out (including some cool First Footprints teaching resources).
It’s amazing to think of what was achieved with such limited computing power, and it really was a turning point in science (and science fiction was never the same afterward).
Apollo 11 Crew
For some cool photo galleries: Guardian, Images from Apollo
Of course, any talk of the moonlandings brings out the crazies (which is why comments are disabled on this post), so here are a couple of other nice clips.
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Moon Landing Mysteries, from National Geographic
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And of course who better to set it to rights than the Mythbusters?
Hybrid Hearts: Stem Cell Transplants 2.0
“Can we use stem cells to make a new heart/eye/lung/liver etc?”
This is the predictable and perennial question that comes up from at least one student when we are looking at stem cells, genetic engineering, cell differentiation and transplanting. Until now, the answer has (perhaps in an oversimplified way) been ‘no’.
We can use stem cell transplants to treat lymphoma. Recently a young woman had a trachea transplant based on stem cell technology. Skin grafts from a patient’s own cultured cells are also possible, as are stem cell-based bladders. However, these are all rather simple technologies.
To treat lymphoma, bone marrow cells are replaced, and are all the same. The trachea transplant was a pre-existing trachea simply coated in the patient’s stem cells to prevent immune rejection. Skin transplants are basically sheets of epidermis that cover a wound, yet do not have the intricate functions of original skin: temperature regulation, secretion, senses. The bladder is a bag.
The challenge with using stem cells to transplant a more complex organ, such as a heart, is that it is not a simple sheet made of one type of cell. It is complex 3D structure, with a range of cells performing specific tasks within the organ. These cells have differentiated to perform their functions: cardiomyocytes (beating cells), vascular endothelial cells (smooth internal surfaces) and smooth muscle cells (blood vessel walls).
How can we get the stem cells to become the right type of cell, in the right position?
The answer to this question could be the key to opening up new doors in the search for viable transplantable organs in medicine, and bears much in common with the trachea case. It also marks a return to form for the NewScientist YouTube channel, who have this short clip of the new hearts in action:
A full article to accompany the footage is here.
In a nutshell:
Decellularised pig heart: the scaffold (NewScientist)
1. Find a suitable transplant organ, such as a pig’s heart.
2. Strip of all cells and DNA, using a detergent. Only the collagen ‘scaffold’ remains, as in the image of the decellularised heart to the right.
3. Coat the scaffold with the recipient’s stem cells.
4. Ensure that the blood supply is adequate and will provide the right signals for differentiation.
What is amazing in this case is how the cells ‘knew’ what specialised cells to become. The leader of the research group, Dr. Doris Taylor, puts it down to the mechanical stimulus of the pressure of the blood in the vessels and chambers and chemical signals from growth factors and peptides that remained on the stripped heart structure.
They even went as far as replacing a healthy rat’s heart with one of these new hybrid hearts. The rat survived for the trial, but she says they need to focus on producing more muscular hearts in order to ensure long-term survival of transplant recipients.
Food for thought:
Read the whole article and some of the links within it. Discuss these questions:
1. What are the potential uses for this kind of transplant technology?
2. What are the current limitations of this method and how might they be overcome?
3. What are the ethical issues related to using hybrid (pig-human) organs in medical transplants? How would you feel if you were the patient?
4. Who are the various stakeholders in this technology and what are their viewpoints?
Useful Sources:
Dr Doris Taylor’s research page from the University of Minnesota
NewScientist Article: Hybrid hearts could solve transplant problem
BioAlive stem cells links and resources
Can stem cells repair a damaged heart? from the NIH
Research reveals how stem cells build a heart, from Harvard news.
Periodic Table for Biologists
Shortlink to this page: http://is.gd/iBiologyPTable
Click on this link to go to the periodic table page and download the A0 poster: http://is.gd/iBiologyPTable
Biotech: The Musical (re-up)
Science + music + YouTube = awesome.
Here are some comedy highlights:
Bio-Rad are the leaders when it comes to making silly music videos to promote their products. The classic ‘PCR Song‘ is great for the Genetic Engineering and Biotechnology topic:
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And you’ve got to love their follow up, GTCA So Fast – touting enzyme supermixes for the PCR process – this would fit in the DNA Replication section:
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Mass Spec-tacular for the chemists (Reach that Peak):
More musical mayhem after the jump…
Defence Dynamics: Ministry of Defence Multimedia Science Resources
click for Science resources
There is also a section for students to access, with access to some of the multimedia resources in the teachers’ area.
End of Year Exams: Online Revision Tools
Quia.com: go to the shared area for free quizzes and games
It’s that time of year again: Middle and High School semester exams. Make sure you know what is going to be covered in your exams and study effectively. Here are some links to help make your study more fun.They are for free and online services only. Don’t forget all of the resources we have on the school network.
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Quizzes and Vocabulary:
Quia.com/shared for lots of games for all subjects, including ‘Rags to Riches’ (Who Wants to be a Millionaire). The Grade 8 Chinese students had fun here.There are lots of vocab and flashcard activities for ESL/CAT students.
FlashcardExchange is a huge resource of flashcards for students to study keywords and terms. Some sets are based on diagrams and images, such as in Science. You can test yourself, play memory games and keep track of your progress. Awesome. If that’s not enough, you can make your own sets.
Quizlet.com has more flashcards and an interesting game called scatter for each set. Free and online, so try it!
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Mind Mapping online
Genetics Concept Map - made in CMap tools
bubbl.us is my favourite (and easiest to use) online mind-mapper. Have a go (no sign-up needed)!
BBC Bitesize also have one which is online and free, but can be a bit frustrating.
Mindomo works well and can be used collaboratively. It looks good, but requires a sign-up.
The best for concept mapping (we describe each relationship on the connector) is CMap tools, which is free but needs to be downloaded and installed. It is excellent, though. This Genetics review was made using it. For the answers, click here.
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OK, get to work!
Pandemic II: Educational Flash Game
Pandemic II: Spread the World
Thanks to the excellent NotExactlyRocketScience blog for posting the link to this game. Pandemic II is a complex flash game based on strategy, evolution (though more like design) and the spread of disease. The premise is simple – take a pathogen (bacteria, virus or parasite), and watch its spread across the globe. Along the way you can alter the pathogen to change its properties, making it more infectious, more lethal or less noticeable. The aim of the game is to wipe out the population of the world.
It is easy to save using Firefox add-ons.
Check out the game here: http://www.crazymonkeygames.com/Pandemic-2.html
And the tutorials here:
Is it better than the addictive Magic Pen Game or Foldit?
Have a go!
i-Biology 