S3 biology students ex-cell…

S3 Standard Grade Biology pupils have recently been learning about cells as part of their studies. Class teachers Miss Macauley and Mrs Binnie and visiting teacher, Mr Scott, set the pupils a challenge of demonstrating what they know about cells by making a model of an animal or plant cell for homework.

The pupils concerned are a creative bunch but they ex-celled (see what we did there) in showing off their knowledge and demonstrating their creativity too. House points were up for grabs in this particular activity and there was more than just pride at stake.

Some of the cell models can be seen below…

In 1st Place, winning points for GRANGE, was CIARA HARVIE

In 2nd place, also winning points for GRANGE was LAURA O’BRIEN

In 3rd place, shy and retiring Amy from Seton was reluctant to appear on camera but she still secured house points for the reds.

Here are some of the class efforts – we are certain everyone will enjoy their creativity. We should point out also that the winners were selected by the class through a secret ballot – with each pupil peer reviewing the models against success criteria agreed before the task was set.


Toxic problem…

There is a chemical that is very dangerous. If this chemical is inhaled, it can be fatal. Under certain conditions, contact with the skin may cause a burn. However, once a person’s body becomes dependant upon this chemical, prolonged separation will almost certainly cause death. Although scientists are well aware of this chemical and it is found in nearly every drinking source, nothing is being done to try to eliminate it…

But what is this chemical?

Answer to “Why is bird pooh white”?

Not much in the way of answers!

Anyway, most bird pooh isn’t actually faeces but the bird equivalent of urine (uric acid).
There are some birds like grouse and the ptarmigan that produce pooh that is quite fibrous as thy eat a lot of plant material (heather etc) or roughage as we sometimes call it but these still have wee bits of white pooh it in (uric acid)

Owl pellets are not ‘poohed’ out but bones and hair that have been puked up. Quite a lot of other birds also do this.

All vertebrates (animals with a backbone) need to get rid of nitrogenous waste (from breakdown of protein). We do it in the form of urine. This needs water to dissolve it and allow us to get rid of it. Reptiles and birds didn’t have the advantage of  lots of water to get rid of their nitrogenous waste as they evolved to fill niches and habitats on land. The white semi-solid sludge is uric acid.This is insoluble and birds and reptiles don’t therefore waste water getting rid of it.

Another interesting explanation is that as birds and reptiles are egg-laying, any water soluble toxins like urine would build up in the egg and poison the developing youngster. As uric acid is insoluble it will not poison the young.

Last theory is Prestonpans seagulls simply enjoy the domino-look of white marks on my black car.

You decide!!

A race to the bottom…

A solid block of iron and an equally heavy iron sphere are released from the top of a slope.

Assuming that the friction from the slope has a negligible effect on the velocity of the block and the sphere, which of the two will get to the bottom first?



Puzzle Tower

Suppose you have an infinite number of bricks and no cement or another material to connect the bricks to each other. You would like to build a tower like the one in the figure. How many bricks do you need in order to build a tower in which the highest brick is shifted three bricks with respect to the lowest brick?

An Archimedes riddle…

Archimedes was no slouch! The Greek mathematician was also a physicist, engineer, inventor and astronomer in his spare time!

He is most well known for his “Eureka moment”…

The most commonly related anecdote about Archimedes tells how he invented a method for measuring the volume of an object with an irregular shape. According to Vitruvius, a new crown in the shape of a laurel wreath had been made for King Hiero II and Archimedes was asked to determine whether it was of solid gold – or whether silver had been added by a dishonest goldsmith. Archimedes had to solve the problem without damaging the crown, so he could not melt it down in order to measure its density as a cube (which would have been the simplest solution).

While taking a bath, he noticed that the level of the water rose as he got in. He realised that this effect could be used to determine the volume of the crown. For practical purposes water is incompressible, so the crown would displace an amount of water equal to its own volume. By dividing the weight of the crown by the volume of water displaced, its density could be obtained.

In other words, the density of the crown would be lower if cheaper and less dense metals had been added…

Archimedes then took to the streets naked  (so excited by his discovery that he had forgotten to dress!)  crying “Eureka!” (“I have found it!”)

So what is your Archimedes Riddle?

You are sitting in a rubber boat in a swimming pool. In the boat lies a stone. You throw this stone from the boat into the pool. Will the water level in the pool rise or drop?

Over to you…