Category Archives: IGCSE
For most students you will be enjoying a well earned break over Easter weekend after what I’m sure has been a busy and frantic school term. However, when it comes to Monday or Tuesday you will probably be searching for some motivation to start your revision. Getting started can be the hardest part of revision, my advice is to plan plan plan. You can spend a lot of time procrastinating otherwise but if you wake up and you know exactly what you are meant to be studying that day you will get started much quicker. You can also tick off tasks as you complete them throughout the day. I recommend three sessions of revision per day, with decent breaks in between and two at the weekend.
Spend this weekend planning what you want to achieve over the next three weeks. Make sure all your subjects are covered in the right amounts and write specific tasks, such as ‘complete paper 1’ or ‘notes on bonding’ rather than just the subject name.
I am very pleased to announce that my first eBook has been published on the Apple iBooks store.
It has been designed for iBooks and will work on iPad, Mac and iPhone (depending on operating system).
It is hopefully the first in a series of books covering the IGCSE course. This first book is FREE and covers the sections on life processes and classification. It contains interactive multiple choice questions at the end of each section and practice diagrams to label.
Why not download it now and give it a 5* rating?
Some of the hardest questions in IGCSE Biology are the 6 marker questions and the paper nearly always finishes with one which is more than often about carrying out an experiment. As there is no coursework for this course they must make sure they test you on your experimental knowledge throughout the paper.
If you can master these questions you are giving yourself a good chance of achieving a top grade.
In my new revision resource I have written 10 original example 6 marker questions followed by a mark scheme for each one. You can download it here:
Note carefully how many of the answers are looking for the same things, especially in the practical questions. The key is to think about the variables.
Remember that the aspect the scientist is altering is the independent variable. Whatever they measure or record in the experiment is the dependent variable and all other variables in the experiment must be controlled. If you explain how to vary the independent variable, how specifically to measure the dependent variable and how to control the other variables then you should do well.
One of the most important parts of IGCSE Biology is to be familiar with the key diagrams. I have therefore created a great revision PowerPoint that contains the 25 most important diagrams on individual easy print slides. Also included are all the answers. If you are a teacher these are great for testing your class, if you are a student you can print multiple copies and try them until you get them all right. Click on the image below to purchase this new resource:
You can download a free diagram of the heart by clicking this link.
Included in the presentation are diagrams for: the kidney, urinary system, digestive system, reproductive system, the leaf, the eye, a motor neurone, the circulatory system, plant cell, animal cell, sperm cell, menstrual cycle, nitrogen cycle and many more.
I have just uploaded a new video and TEDEd lesson on the digestive system which I have been putting together for a while. I am also planning on updating my older video resources to bring them more up to date.
I will be posting a Christmas Special video in the next few days so subscribe on YouTube to see it first.
I have been meaning to write this post for a while in order to let you know what the plans are going forward for mrexham.com, and this week seemed like as good a time as any with the GCSE results coming out and a new academic year starting.
Firstly I would like to thank everyone who has used the website in the last year, I have received some great emails and tweets and I am really glad that it’s been useful to so many people. I’ve now decided to take mrexham.com in a few different directions. Firstly I am making some of my key resources, which take the most time and effort to make, available to purchase through sellfy.com. This has meant spending more time on these resources to make them as clear and informative as possible, and it has also given me the impetus to make more of them! There will soon be a PowerPoint for each section of the IGCSE course along with revision quizzes.
I will continue to make free resources as well, including Quizlets, revision sheets, YouTube dissections, practical demonstrations, worksheets and I also intend to write Socrative quizzes for teachers.
Given that there will be a new A-Level starting in 2015 (read the Ofqual announcement here) I will no longer be adding to the current A-Level pages and resources. Instead I will focus on making new resources ready for the launch of the new linear A-Level next year. I will also be blogging about the various courses and exam boards offering Biology A-Level as my department make their decision about which to choose.
Thank you once again for all the positive feedback and please let me know if there’s anything else you’d like to see on mrexham.com!
Today in London the first ever lab-grown hamburger was cooked and eaten. Would you eat meat grown in a lab? Before you answer the question you should know more about how the burger was made and more importantly, why?
How the burger was made?
It was made by Professor Mark Post from Maastricht University in Holland using using stem cells taken from a dead cow. These are muscle specific stem cells that are then provided with nutrients so that they can divide over and over again by mitosis. The cells naturally come together to form small fibres called myotubes. These are electrically stimulated to make them contract and relax, this builds the muscle fibres just like going to the gym. They are then combined with fat grown in a lab and a few other additives such as beetroot for colour and then pressed into a burger. Therefore only a few cells are needed to make a whole burger, and potentially tons of meat.
Watch the video below to learn more about stem cells.
Why was the burger made?
- We currently have a huge demand for meat in the world. The increase of the middle classes in countries such as India and China has further increased demand for meat and also the cost. Artificial meat could therefore provide a cheaper alternative to real meat.
- The population is increasing at an exponential rate. Current methods of producing meat will not be sustainable in the future and so artificial meat may be a good solution as it can be grown using 99% less land. Using less land for animals means more can be used to grow crops such as fruit and vegetables which are healthy and much needed as the population continues to grow.
- Current methods of meat production are very bad for the environment. A lot of energy is used to farm meat, from producing the feed to housing and slaughtering the livestock. However the major issue is methane. Ruminants such as sheep and cattle release a lot of methane due to their digestive system. Methane is a greenhouse gas which is 25 times more powerful than carbon dioxide. This is contributing hugely to global warming and consequently climate change. In contrast, lab-grown beef uses 45% less less energy and produces 96% less greenhouse gases (Source: Environmental Science and Technology Journal).
- Another issue is animal welfare. Many vegetarians and vegans have taken the life choice not to eat meat because they disagree with how animals are treated in the production of meat. Meat grown in the lab avoids the need to grow animals and slaughter them in the way we do now. Only one cow would be needed to make thousands and thousands of burgers.
Watch this video to see a nice summary of these issues.
What are the problems with lab-grown meat?
- It costs about £250,000 to make lab-grown beef. However in the future when the cost of the technology involved becomes cheaper it could be economically viable to make meat on a mass scale. The question is will it ever be cheap enough to actually be used by the countries where it may be needed the most?
- The taste of the meat may not be as good. At this afternoon’s tasting Austrian food researcher Ms Ruetzler said: “It’s close to meat, it’s not that juicy, the consistency is perfect”. It’s therefore expected that other additives will need to be used to make the meat taste better and also make it more healthy then regular meat.
- Perhaps we should be focussing on managing our current issues with food such as food wastage – at the moment we throw away a 6th of all food!
- The thought of growing food in a lab this way can be off-putting to people.
So now you know the details, have you made up your mind? If you’re still not sure watch this TED talk by Prof Mark Post and see if he can convince you.
Please comment below with your opinions on this amazing scientific development.
Photo credit: David Parry/PA
Plant reproduction is often seen as dull and boring compared to animal reproduction but it’s actually incredibly interesting. The lastest video to be uploaded to my YouTube channel shows me dissecting a flower to help you learn about it’s anatomy and how the two processes of pollination and fertilisation occur.
If you’d like to learn more about the life cycle of a plant including seed growth and dispersal, why don’t you click here and work your way through the great animations and activities available. You could also test your knowledge of flower anatomy by trying this quick quiz.
It’s important to remember that pollination is not just carried out by bees, watch this amazing video on YouTube about ‘The Beauty of Pollination’. There is some fantastic footage of insects and birds collecting pollen from anthers.
I know a lot of recent visitors to the website have enjoyed using Quizlet to help with their revision. For anyone who hasn’t used Quizlet before you can learn what it is, and how to use it, by clicking here. There are now two new quizes available to help you revise Food and Digestion, just click on the links below to access them:
For anyone studying this topic I’d recommend watching Hank Green’s YouTube video below. He will take you on a crash course through the bowels of the human digestive system and explain why it’s all about surface area!
Hank’s YouTube channel is a great resource for anyone studying Biology, it has 40 different videos covering topics such as photosynthesis, meiosis, natural selection and ecology. Why don’t you check it out!