GCSE CORE SCIENCE B2 P2 C2 Higher 5th Friday 2015

Darwin concluded that organisms that are the best adapted would be the more successful competitors and would be more likely to survive and reproduce. This idea is known as 'The survival of the fittest'. The more successful organisms that survive are more likely to reproduce therefore more likely to pass on the adaptations that made them successful to their offspring. The organisms that are less well adapted are less likely to survive and reproduce therefore unable to pass on their characteristics to the next generation. Eventually the more successful adaptations become more common in a population and the species starts to change - it evolves.

Hello is anyone doing this exam tomorrow?
Are you prepared?

XD you now have an online friend who is me

Hello is anyone doing this exam tomorrow?
Are you prepared?

I am. I am kind of prepared but I need to revise physics again. Aiming for an A at least. I would love an A* overall but not sure that's possible as I got a B in my controlled assessment.

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you know what topics are most likely to come up?

Yes I have revised so much for biology. I hope I do well. I have done by additional science and It went good, so I am hoping it is a good paper

How did you all find it?
Can we share some answers please, just to get some ideas on how many I got right. What did you get for the solar panel question? I think I got 120000 something like that because the answer above it was 50 so you times it by 60MJ?

I have forgotten many of the answers
So what did you get for the last question? I got Player A

Also for the question where you had to write the genus I accidentally wrote the second word Mikado or something

How did you find it overall?
Yep I got player A but didn't have time to answer the whole question or explain my points *sigh*.
Was it just me or was it difficult to construct the bar chart? I had to use 2 squares for each letter :/
And also were the mean percentage answers a decimal with a minus??

If you get 2 A*'s in the exams you can most surely get that A*. Don't lose hope, just keep positive, I know you can do it!

Can anyone explain Alpha,Beta and Gamma radiation please?

All are different types of ionising radiation
An nucleus is unstable because the repulsion between the positively charged protons is greater than the attraction between the neutral neutrons and protons
An atom that has an unstable nucleus is called radioactive; it will attempt to become stable by changing its nucleus; this is called radioactive decay

Alpha = least penetrating, can be stopped by a few cm of air as it is very ionising
In which two neutrons and two protons are emitted. This is the most ionising because it has two positive charges which are strongly attracted to the electrons of an atom. Also, alpha particles have a larger mass than the other types and so pull electrons towards them
In this type the nucleus is unstable because there are too many protons; usually occurs for Z > 82

Beta = Middle penetrating/middle ionising, can be stopped by a few cm of aluminium
Beta -
This is the emission of an electron from the nucleus because there are too many neutrons for the nucleus to be stable. Therefore a neutron (made up of down down up quarks) turns into a proton (made up of up up down quarks) by changing an down quark to a up quark. This causes an electron to be emitted to balance the charges - as there is now one extra positive charge
Beta +
This happens when there are too few neutrons so a proton turns into a neutron, emitting an antiparticle called a positron (which is an anti-electron with a charge of +1). In this an up quark in a proton turns into a down quark, causing it to turn into a neutron.

Gamma = highly penetrating, least ionising, can be stopped by thick lead or concrete
This is basically an emission of energy that usually happens after another type of radioactive decay, when the nucleus is left in an excited state. Therefore this excess energy is emitted as a very high frequency electromagnetic wave called a gamma ray. This is simply a loss of energy; it does not change the mass of the nucleus

Anyways please could anyone post the mark scheme for todays exam?