I have been experiencing a renaissance in my teaching life ever since I decided to embrace my ignorance on all issues biological (still can’t learn to love Chemistry unfortunately, but there may still be time).
We did heart dissections the other day.
I spent an evening searching for related videos on youtube. I am a firm advocate of the notion that unless you have been ‘prepped’ in terms of what to look for,you may well end up looking at an amorphous mess. In other words both the student and the teacher can be looking at the same object and see two completely different things. Discovery Learning obviously has its place, but as a teacher it’s all about knowing when to mix and match.
As usual there was a lot of sifting to be done before ending up with final list. As always, this is a labour of love.
Along the way I picked up the following nuggets:
- Each day your body makes 200 billion new blood cells.
- White blood cells live for two weeks, Red blood cells live four months.
- You have about 5 litres of blood in your body; when you donate blood you are giving up about half a litre.
- Your heart pumps about 70 times a minute, which equates to over 100,000 times a day!
- When exercising your heart-rate doubles to about 140 times a minute.
- Your heart is about the size of an apple.
- Blood takes about 35 seconds to make a round trip when relaxed, or 15 seconds when exercising.
- Heart Disease is Ireland’s number one cause of death.
- Irish women have almost twice the rate of death from heart disease as the EU average.
- The difference between a Heart Attack and a Stroke:
Both are a result of blocked arteries: In a heart attack the blocked arteries are feeding the heart muscles, and those muscles are not getting the oxygen and nutrients they need to function.
With a stroke, the blocked arteries are in the brain, and those brain cells are not getting what they need to function… depending on where in the brain it occurs, different functions are affected (e.g., speech, writing ability, and so on…)
A third place where blocked arteries occur is in the lungs… then it is called a pulmonary embolism.
Ms Salter gave me a crash course on the dissection itself the day before, so I knew just about enough to set the troops on their way. They had an absolute ball, so why is this not a mandatory activity? Why should non-specialist teachers like me get away with not doing such a memorable activity with my students?
I have since been informed that we can get hold of hearts which have all the tubes coming out of them, which should be much more educational.
I did tape the students doing the dissection itself, but accidentally taped over it. Sorry!
If doing it again I would tell the students that their task is to teach another group about what they have learned. It tends to focus the mind!
I have put the youtube links on my website here.