week 2 BLOOD TYPES

BLOOD types blood types are usually passed down though parents

here is a table showing diffrent blood types and how they are recognised

here is a load of info on blood types so you better be ready to get confused or get a headache. to make it easier ive made it as simple as possible or your head will probably explode

get your concentration hats on..... NOW

If you have blood group A then you've got A antigens covering your red cells.

Blood group B means you have B antigens,

while group O has neither,

and group AB has some of both.

The ABO system also contains lots of little antibodies in the plasma, antibodies being the body's

natural defence against foreign antigens.

So blood group A has anti-B in their plasma,

blood group B has anti-A (you probably get the picture at this stage).

To complicate matters though, group AB has none and group O has both of the antibodies.

Which means giving someone blood from the wrong ABO group could be fatal.

The anti-A antibodies in group B attack group A cells and vice versa.

Which is why group A blood must never be given to a group B person. Group O negative is a different story.

the Rh antigen changes everything.

Some of us have it, some of us don't.

If it is present, the blood is RhD positive, if not it's RhD negative.

So, for example, some people in group A will have it, and will therefore be classed as A+ (or A positive).

While the ones that don't, are A- (or, wait for it...A negative).

And so it goes for groups B, AB and O.

This effectively doubles the number of different blood types to be matched, because you shouldn't mix blood type A+ with blood type A-.

84% of the population is Rh positive. (And yes, that means the other 16% of the population is running around with Rh negative blood.)

this is my blog on blood,

hope your head gets better soon

Week 1 FINGERPRINTS

Fingerprints are used to identify us,

we all have unique prints,

none are ever the same,

not even twins.

there are different types of prints like:

Loop

whorl

ark

CSI usually use a powder substance to trace fingerprints at a crime scene

or

they may use a laser scanner like this picture at the top

or

they may use a spray which reveals fingerprints on difficult surfaces(paper etc.)

But sometimes,

when they match fingerprints to a suspect,

they get it wrong like they did with Shirley mckie

here is what happened:

Shirley McKie
Error in identification. Shirley McKie was a police detective in 1997 when she was accused of leaving her thumb print inside a house in Kilmarnock, Scotland where Marion Ross had been murdered. Although detective constable McKie denied having been inside the house, she was arrested in a dawn raid the following year and charged with perjury. The only evidence was the thumb print allegedly found at the murder scene. Two American experts testified on her behalf at her trial in May 1999 and she was found not guilty. The Scottish Criminal Record Office (SCRO) would not admit any error, but Scottish first minister Jack McConnell later said there had been an "honest mistake".
On February 7, 2006, McKie was awarded £750,000 in compensation from the Scottish Executive and the SCRO.[ Controversy continues to surround the McKie case with calls for the resignations of Scottish ministers and for either a public or a judicial inquiry into the matter.]

this is my study on fingerprints

what i am going to do

Over the next few weeks I am going to be doing the following:

week 1 fingerprints

week 2 blood types

week 3 DNA fingerprinting

week 4 chromatography

week 5 microscopes

week 6&7 case study (looking at a particular crime and how it was solved)

hi everyone

Hello, I'm Charlotte W

I'm in 8bh2 for science and this is my homework project about ... C.S.I crime scene investigators and their methods of finding diffrent evidence.

I will put up a timetable of what I will be doing on this blog on in a few days and keeping you updated on my work.