Biology Experiments

Fortinbras'

I know tuesday seems like miles away, but we best get down to it,

I am majorly ****ed for the experiments

Could people please post sample experiment questions and answer
esp. for the DNA experiment

as in what does this step do etc.


Thank You!

Fortinbras'

Do you think the heart will deffo not come up as it did last year??

angeldelight

Hmm ok teh DNA experiment then...

Reason for chopping the onion: Breaks cell walls allowing cytoplasm to leak out

Washing up liquid breaks down lipids in phospholipid bilayer resulting in release of nuclear material from cell

Salt reduces the attractive forces between DNA molecules and proteins by shielding DNA and causing it to clump together

Heating solution to 60 degrees for 15 mins means D. Nases from lysosomes are broken down (prevents destruction of DNA by cell itself). After 15 mins DNA will start to be broken down by heat

Cooling mixture in ice decreases the rate of chemical reactions slowing the action of any remaining enzymes before they damage the DNA

Protease enzyme breaks down proteins assocaited with DNA

Ice-cold ethanol dehydrates DNA causing it to appear at interface of 2 liquids. Needs to be ice temp as DNA is soluble in ethanol at room temp


That's going on memory from last June so if there's anything I missed I'm sure someone else will add it in!

angeldelight

Have you any specific questions?

Fortinbras'

angeldelight wrote:

Have you any specific questions?

Questions on any experiment I am asking people in general,
maybee the IAA one

Camogie Playa

i hate the iaa experiment

Scarinae

Camogie Playa wrote:

i hate the iaa experiment

Bad news... That one is tipped for this year, but then again so is an enzyme experiment so maybe you'll be grand

Fortinbras'

Fishie wrote:

Bad news... That one is tipped for this year, but then again so is an enzyme experiment so maybe you'll be grand

If its tipped it is good, you can just study it and get obver it STOP it's not as if it os especially hard STOP
so that means that DNA IAA and an enxyme are tipped? STOP
the tips could be bogus though meh STOP

wheresthebeef

here's a very brief summary of some of the experiments in graphics format
i only did it myself so i cant guarantee is 100% perfect. but i usually get my A1's or A2's in exams.

http://www.iol.ie/~exon/Experiments.png
its big so make sure you view it at 100% or else it will look unreadable

Fortinbras'

wheresthebeef wrote:

here's a very brief summary of some of the experiments in graphics format
i only did it myself so i cant guarantee is 100% perfect. but i usually get my A1's or A2's in exams.

http://www.iol.ie/~exon/Experiments.png
its big so make sure you view it at 100% or else it will look unreadable

Thank you are they the mandatory ones/are there mandatory ones? whats the deal with their being loads in the book which dont come up? how do u know?


ALso the heart came up last ear does that mean it wont come up this year, what do you think?

wheresthebeef

i'm not sure. there used to be a really strict pattern on the old exam and you could tell what was coming up. but since the new course is only in one year there is no way of knowing.
they are most likely going to pick different questions than last years ones because they will want to test out as much of the new syllbus. so anything that came up last year might be unlikely to come up this year.

i also have powerpoint presentations that cover all the chapters in the book. and a PDF with all the experiments done out in full. if anyone wants these things PM me with your real name, school and email address. and i will send them on a per person basis by attachment.

Fortinbras'

wheresthebeef wrote:

i'm not sure. there used to be a really strict pattern on the old exam and you could tell what was coming up. but since the new course is only in one year there is no way of knowing.
they are most likely going to pick different questions than last years ones because they will want to test out as much of the new syllbus. so anything that came up last year might be unlikely to come up this year.

i also have powerpoint presentations that cover all the chapters in the book. and a PDF with all the experiments done out in full. if anyone wants these things PM me with your real name, school and email address. and i will send them on a per person basis by attachment.

just to spare you the hassle, all experiments can be found on www.leaving-cert.net and are excellent

wheresthebeef

i have that lab manual thing as well but its too long winded.
i have a copy of all the experiments from the text book scanned and converted to PDF. its only one page per experiment as opposed to the Lab Manual which takes up about 3 pages per experiment in most cases.

but if they are already online. thats grand.

Fortinbras'

AN more answers to those annoying Q's they ask on the experiments?

Camogie Playa

in the iaa exp, why do you leave the dish on its side?

wheresthebeef

cos of geotropism i think

angeldelight

Yep it is cause of geotropism - to ensure the shoots grow upwards and the roots downwards so you can measure them properly

Camogie Playa

thanks a million for that, never could find the answer!