Biology Paper:1 Help plz...how to revise?

[XPFMember]

AsSalamoAlaikum Wr Wb!

So got bio p1 tom, inshaAllah...
the the thing is i only solved 4-5 papers...2002 onwards...

What do you people suggest me to do? considering there isn't much time left...how d I revise...which papers I do...?

Help will be much appreciated...

JazakAllahu Khairen...

 

[egy]

AsSalamoAlaikum Wr Wb!

So got bio p1 tom, inshaAllah...
the the thing is i only solved 4-5 papers...2002 onwards...

What do you people suggest me to do? considering there isn't much time left...how d I revise...which papers I do...?

Help will be much appreciated...

JazakAllahu Khairen...

go through the papers which u solved and on through ur notes ... on YouTube there is some videos which is very nice and helpfull for the process such as Mitosis , Transcription , Translation ...etc .

i wish that i helped ..... Good Luck ..

 

[thunderingthunder]

AsSalamoAlaikum Wr Wb!

So got bio p1 tom, inshaAllah...
the the thing is i only solved 4-5 papers...2002 onwards...

What do you people suggest me to do? considering there isn't much time left...how d I revise...which papers I do...?

Help will be much appreciated...

JazakAllahu Khairen...

I think, since you have not gone through many papers,it would be best to revise your notes and memorise some important points from your book(summaries at the end of chapter are of great help)..Plus if you have the book "1000 biology MCQ's". go through the important points they have summarized at the start of every chapter...
All the best for your paper

 

[Soulgamer]

AsSalamoAlaikum Wr Wb!

So got bio p1 tom, inshaAllah...
the the thing is i only solved 4-5 papers...2002 onwards...

What do you people suggest me to do? considering there isn't much time left...how d I revise...which papers I do...?

Help will be much appreciated...

JazakAllahu Khairen...

Just asking, we had alot of days for the mcq's so why did you only solve 4-5 papers. My advice is do the 2011 and 2010 papers to get a grasp of how examiners are testing our knowledge and go through the important stuff like learning the diameter of cells, calibration etc. May ALLAH help you and all of us Ameen!

 

[XPFMember]

Just asking, we had alot of days for the mcq's so why did you only solve 4-5 papers. My advice is do the 2011 and 2010 papers to get a grasp of how examiners are testing our knowledge and go through the important stuff like learning the diameter of cells, calibration etc. May ALLAH help you and all of us Ameen!

ehemm....was doing physics...n wasting time...

 

[XPFMember]

And btw, if any one compiled any important points, do share them please....

I think, since you have not gone through many papers,it would be best to revise your notes and memorise some important points from your book(summaries at the end of chapter are of great help)..Plus if you have the book "1000 biology MCQ's". go through the important points they have summarized at the start of every chapter...
All the best for your paper

nopes i don't have the 1000MCQ's one...

 

[thunderingthunder]

And btw, if any one compiled any important points, do share them please....


nopes i don't have the 1000MCQ's one...

oho..i dont have the PDF version or else i would have uploaded it for you
Go through the definitions given at the end of the book and do remember to go through 2010 and 2011 past papers..
Best of luck for your Exam!!

 

[XPFMember]

oho..i dont have the PDF version or else i would have uploaded it for you
Go through the definitions given at the end of the book and do remember to go through 2010 and 2011 past papers..
Best of luck for your Exam!!

oh...jazakAllah...it's ok...u'll be rewarded for ur good intentions inshaAllah...!!!!!!!!!!!!!!!!!

ok...i will inshaAllah...i guess i did papers 2002-2006....might be i'll have to leave few papers...will see...
may Allah help us all...and may we all score 40/40 inshaAllah...

 

[Oliveme]

AsSalamoAlaikum Wr Wb!

So got bio p1 tom, inshaAllah...
the the thing is i only solved 4-5 papers...2002 onwards...

What do you people suggest me to do? considering there isn't much time left...how d I revise...which papers I do...?

Help will be much appreciated...

JazakAllahu Khairen...

WS I would definitely suggest you do the latest past papers especially May/June and Oct/Nov 2010 and 2011. This is when the papers esp paper 1s start getting harder. Time yourself. You will find that you take more time for these papers as compared to the older ones. this happened to me in chemistry paper 1. I did only 2002-2006 and suffered because I didn't realize the papers had become a lot harder and in the real exam I ran BADLY out of time. I would it's a MUST to do these papers. do one of each variant since there is only little time. Good luck may Allah help us all.

 

[thunderingthunder]

oh...jazakAllah...it's ok...u'll be rewarded for ur good intentions inshaAllah...!!!!!!!!!!!!!!!!!

ok...i will inshaAllah...i guess i did papers 2002-2006....might be i'll have to leave few papers...will see...
may Allah help us all...and may we all score 40/40 inshaAllah...

InshaAllah
Ameen!!

 

[XPFMember]

WS I would definitely suggest you do the latest past papers especially May/June and Oct/Nov 2010 and 2011. This is when the papers esp paper 1s start getting harder. Time yourself. You will find that you take more time for these papers as compared to the older ones. this happened to me in chemistry paper 1. I did only 2002-2006 and suffered because I didn't realize the papers had become a lot harder and in the real exam I ran BADLY out of time. I would it's a MUST to do these papers. do one of each variant since there is only little time. Good luck may Allah help us all.

JazakAllah...wud surely do that..
so i guess...i shud do papers nov 2011 backwards...as many as i can do inshaAllah.
may Allah help us alll n give us success in both worlds aameen....ya rab'al a'alameen..!

 

[thunderingthunder]

Sorry,I know that it is very late now but I just found these somewhere and thought to put them up here..
Hope these are helpful
Biology : Last minute Revision for Unit 1 (Molecules and cells)
1.Molecules

Metabolism
Metabolism is a term to describe all reaction which is taking place within a cell and is separated into two types which are
- anabolic = compounds being built up
- catabolic = compounds being broken down


1.1 Water
The water molecule is a molecule which is made up from 2 ahydrogen atoms and 1 oxygen atoms. It is bounded by 2 covalent bonds and has is polar.
The reason why water molecules are important for living organisms are because :
1) They are important solvents since they are polar
2) Important coolants for excessive metabolic reactions
3) Important for insulation since they have high specific heat capacities
4) It is a very good mechanism for transport since they are highly cohesive
5) Important reagents for chemical reactions ( such as hydrolysis and photosynthesis )

1.2 Carbohydrates
Separated into 3 types which are monosaccharides,disaccharides and polysaccharides

Monosaccharides
-they are three main types of monosaccharides which you have to know in this level which are
Pentoses - Such as ribose (with formula C5H10O5) and fructose
Hexose - Such as alpha and beta glucoses

-All members of monosaccharides are reducing since they have the aldehyde groups,therefore they will cause a brick red persipitate to form when tested with benedict`s solution.

Disaccharides
-You would need to know 3 types of dissacharides in this level which is
1)Lactose - Formed between glucose and galactose and is bounded by 1,4 glycosidic bonds (found in milk)
2)Maltose - Formed by 2 molecules of glucose and is bounded by 1,4 glycosidic bonds (found in starch after being hydrolysed)
3)Sucrose – Formed by a molecule of glucose and a molecule of fructose bounded by 1,2 glycosidic bonds (Found in most plant since it is used to transport sugary compounds)

-The formation of bonds between 2 monosaccharides is called condensation and the breakage of these bonds are called hydrolysis.Hydrolysis of these bonds can be brought about by adding dilute HCl.
-Both lactose and maltose are reducing but sucrose is not a reducing sugar.Therefore disaccharides can or cannot be reducing.It is not always a reducing agent.

Polyssacharides
-There are three types of polyssacharides that we need to know at this level which are

Starch
- A polymer of alpha glucose and is bounded by 30% amylose (1,4 glycosidic bonds) and 70% amylopectin (both 1,4 and 1,6 glycosidic bonds)
- It is used as a food storage for plants and is built from the amyloplasts in the cytoplasm of plant cells.
- Starch is an important storage molecule since it is compact,insoluble in water,inert to chemical reactions and is easily hydrolysed when required.

Glycogen
- A polymer of alpha glucose with 1,4 glycosidic bonds but even more 1,6 glycosidic bonds compared to starch since it is even more branched..
- It is used as an energy store in animals and is also found in bacterias
- Glycogen is an important storage molecule since it is compact,insoluble in water,inert to chemical reactions and is easily hydrolysed when required.

Cellulose
- A polymer of beta glucose and is by only 1,4-glycosidic bonds.Therefore it is not branched but arranged in a matrix which is bounded by hydrogen bonds
- It is the constituent of cell walls and can be hydrolysed by ruminant animals by the action of cellulase enzymes..

**all polysaccharides are non reducing sugars.

1.3 Lipids
- Lipids are basically fats and oild that contain elements of carbon,hydrogen and oxygen
- An example of a lipid would be the triglyceride which is formed by glycerol and fatty acids .The bond formed is catalysed by the the process of condensation between the –OH groups of the glycerol and the fatty acids.The bonds formed between them are the ester bonds.Since triglyceride itself is an ester.
- There are two types of fatty acids which are unsaturated and saturated fatty acids.An example of a saturated fatty acid would be stearic acid and unsaturated would be the oleic acid.The difference between saturated and unsaturated fatty acids are the double bonds and the amount of hydrogen present at where saturated acids have more hydrogen and no double bond present.
- The usages of triglycerides are important energy stores,compact,insoluble inwater,releases energy twice the amount of carbohydrates, and provides buoyancy for aquatic animals.
- The usages of fatty acids include the formation of triglycerides and is also required for the formation of phospholipids.

1.4 Phospholipids
- Formed between fatty acids,glycerol and a phosphate group.
- The head is hydrophilic (soluble in water) but the tail is hydrophobic (insoluble in water).
- Therefore phospholipids are used as the main constituents of cell membranes

1.5.Protein
Primary structure
- It is the number , type and sequence of amino acids which makes up a polypeptide chain
- Each amino acid is binded to another acid by peptide bonds by the process of condensation.Amino acids are amphoteric since it has a zwitterion shapes.

Secondary structure
- It is the shape of molecule formed when polypeptide chains are either coiled by hydrogen bonds into a spiral springs ,the alpha helix or linked to form beta pleated sheets
- The alpha helix coils the polypeptide chains and are help in place by hydrogen bonds.An example of this would be keratin.
- The beta pleated sheets are formed by hydrogen bonds taking place between the CO and NH groups .It is very strong but supple. An example would be collagen since it is fibrous.
- Insoluble in water.

Tertiary structure
- It is the folding of a polypeptide to form a globular shape.
- R groups of these proteins are bounded by ionic bonds,disulphide bridges and hydrogen bonds.
- An example would be enzymes.

Quaternary structure
- A complex protein molecule which has more than one polypeptide chains bounded to it.
- An example would be haemoglobin.


Experimental tests
-Bear in mind that most of the unit 1 tests has at least 1 biological test question which can yield up to 5 points and these tests should not be neglected.

Benedict test
- Test to confirm reducing properties of sugars.
- Add a few drops of benedict solution into the sugar and boil.If it shows a brickred percipitate, a reducing sugar is present.Since copper 2+ is reduced in copper +1 which shows are brick red precipitate

Biuret test
- Test to confirm the contents of protein or the prescence of protein.
- Add an equal amount of protein and biuret reagent.A purple-violet color would confirm the prescence of proteins.This can be used as a qualitative test since the color is gets more intense as the protein content increases.

Sudan III test
- To test the for the presence of fat
- Add equal amount of sudan III and fat contents together.A suspension of red liquid and white precipitate on the top would confirm that there is fat present.

 

[Soldier313]

Sorry,I know that it is very late now but I just found these somewhere and thought to put them up here..
Hope these are helpful
Biology : Last minute Revision for Unit 1 (Molecules and cells)
1.Molecules

Metabolism
Metabolism is a term to describe all reaction which is taking place within a cell and is separated into two types which are
- anabolic = compounds being built up
- catabolic = compounds being broken down


1.1 Water
The water molecule is a molecule which is made up from 2 ahydrogen atoms and 1 oxygen atoms. It is bounded by 2 covalent bonds and has is polar.
The reason why water molecules are important for living organisms are because :
1) They are important solvents since they are polar
2) Important coolants for excessive metabolic reactions
3) Important for insulation since they have high specific heat capacities
4) It is a very good mechanism for transport since they are highly cohesive
5) Important reagents for chemical reactions ( such as hydrolysis and photosynthesis )

1.2 Carbohydrates
Separated into 3 types which are monosaccharides,disaccharides and polysaccharides

Monosaccharides
-they are three main types of monosaccharides which you have to know in this level which are
Pentoses - Such as ribose (with formula C5H10O5) and fructose
Hexose - Such as alpha and beta glucoses

-All members of monosaccharides are reducing since they have the aldehyde groups,therefore they will cause a brick red persipitate to form when tested with benedict`s solution.

Disaccharides
-You would need to know 3 types of dissacharides in this level which is
1)Lactose - Formed between glucose and galactose and is bounded by 1,4 glycosidic bonds (found in milk)
2)Maltose - Formed by 2 molecules of glucose and is bounded by 1,4 glycosidic bonds (found in starch after being hydrolysed)
3)Sucrose – Formed by a molecule of glucose and a molecule of fructose bounded by 1,2 glycosidic bonds (Found in most plant since it is used to transport sugary compounds)

-The formation of bonds between 2 monosaccharides is called condensation and the breakage of these bonds are called hydrolysis.Hydrolysis of these bonds can be brought about by adding dilute HCl.
-Both lactose and maltose are reducing but sucrose is not a reducing sugar.Therefore disaccharides can or cannot be reducing.It is not always a reducing agent.

Polyssacharides
-There are three types of polyssacharides that we need to know at this level which are

Starch
- A polymer of alpha glucose and is bounded by 30% amylose (1,4 glycosidic bonds) and 70% amylopectin (both 1,4 and 1,6 glycosidic bonds)
- It is used as a food storage for plants and is built from the amyloplasts in the cytoplasm of plant cells.
- Starch is an important storage molecule since it is compact,insoluble in water,inert to chemical reactions and is easily hydrolysed when required.

Glycogen
- A polymer of alpha glucose with 1,4 glycosidic bonds but even more 1,6 glycosidic bonds compared to starch since it is even more branched..
- It is used as an energy store in animals and is also found in bacterias
- Glycogen is an important storage molecule since it is compact,insoluble in water,inert to chemical reactions and is easily hydrolysed when required.

Cellulose
- A polymer of beta glucose and is by only 1,4-glycosidic bonds.Therefore it is not branched but arranged in a matrix which is bounded by hydrogen bonds
- It is the constituent of cell walls and can be hydrolysed by ruminant animals by the action of cellulase enzymes..

**all polysaccharides are non reducing sugars.

1.3 Lipids
- Lipids are basically fats and oild that contain elements of carbon,hydrogen and oxygen
- An example of a lipid would be the triglyceride which is formed by glycerol and fatty acids .The bond formed is catalysed by the the process of condensation between the –OH groups of the glycerol and the fatty acids.The bonds formed between them are the ester bonds.Since triglyceride itself is an ester.
- There are two types of fatty acids which are unsaturated and saturated fatty acids.An example of a saturated fatty acid would be stearic acid and unsaturated would be the oleic acid.The difference between saturated and unsaturated fatty acids are the double bonds and the amount of hydrogen present at where saturated acids have more hydrogen and no double bond present.
- The usages of triglycerides are important energy stores,compact,insoluble inwater,releases energy twice the amount of carbohydrates, and provides buoyancy for aquatic animals.
- The usages of fatty acids include the formation of triglycerides and is also required for the formation of phospholipids.

1.4 Phospholipids
- Formed between fatty acids,glycerol and a phosphate group.
- The head is hydrophilic (soluble in water) but the tail is hydrophobic (insoluble in water).
- Therefore phospholipids are used as the main constituents of cell membranes

1.5.Protein
Primary structure
- It is the number , type and sequence of amino acids which makes up a polypeptide chain
- Each amino acid is binded to another acid by peptide bonds by the process of condensation.Amino acids are amphoteric since it has a zwitterion shapes.

Secondary structure
- It is the shape of molecule formed when polypeptide chains are either coiled by hydrogen bonds into a spiral springs ,the alpha helix or linked to form beta pleated sheets
- The alpha helix coils the polypeptide chains and are help in place by hydrogen bonds.An example of this would be keratin.
- The beta pleated sheets are formed by hydrogen bonds taking place between the CO and NH groups .It is very strong but supple. An example would be collagen since it is fibrous.
- Insoluble in water.

Tertiary structure
- It is the folding of a polypeptide to form a globular shape.
- R groups of these proteins are bounded by ionic bonds,disulphide bridges and hydrogen bonds.
- An example would be enzymes.

Quaternary structure
- A complex protein molecule which has more than one polypeptide chains bounded to it.
- An example would be haemoglobin.


Experimental tests
-Bear in mind that most of the unit 1 tests has at least 1 biological test question which can yield up to 5 points and these tests should not be neglected.

Benedict test
- Test to confirm reducing properties of sugars.
- Add a few drops of benedict solution into the sugar and boil.If it shows a brickred percipitate, a reducing sugar is present.Since copper 2+ is reduced in copper +1 which shows are brick red precipitate

Biuret test
- Test to confirm the contents of protein or the prescence of protein.
- Add an equal amount of protein and biuret reagent.A purple-violet color would confirm the prescence of proteins.This can be used as a qualitative test since the color is gets more intense as the protein content increases.

Sudan III test
- To test the for the presence of fat
- Add equal amount of sudan III and fat contents together.A suspension of red liquid and white precipitate on the top would confirm that there is fat present.

tx a million

 

[thunderingthunder]

tx a million

my pleasure

 

[Nibz]

Ws.

Go through Nitrogen cycle and learn the definitions of all ecological terms. The last 2-3 MCQs are entirely from these topics so these should be on your finger tips.
Go through the points posted by thunderingthunder and solve recent past papers 2011- backwards as many as you can.

Time issue is not a problem in Biology MCQs. And well, I think, Bio shouldn't be a problem for you.

 

[XPFMember]

thunderingthunder thanks a lot...JazakAllahu khairen!!!!!!

 

[XPFMember]

Ws.

Go through Nitrogen cycle and learn the definitions of all ecological terms. The last 2-3 MCQs are entirely from these topics so these should be on your finger tips.
Go through the points posted by thunderingthunder and solve recent past papers 2011- backwards as many as you can.

Time issue is not a problem in Biology MCQs. And well, I think, Bio shouldn't be a problem for you.

oh sure....that puts me at ease...

inshaAllah.....hope it isn't a problem...

 

[sarahnafea]

YO people of the earth! I have a very very mind-boggling question that will haunt me in my sleep if left unanswered and will haunt you for the rest of your life if you don't answer it (just kidding)....why oh why are all 4 levels of protein structure involved in maintaing the specificity of an enzyme if an enzyme is restricted to a tertiary structure?

 

[osama123]

YO people of the earth! I have a very very mind-boggling question that will haunt me in my sleep if left unanswered and will haunt you for the rest of your life if you don't answer it (just kidding)....why oh why are all 4 levels of protein structure involved in maintaing the specificity of an enzyme if an enzyme is restricted to a tertiary structure?

As the active site is specific for each substrate this is possible due to r-groups of the amino acids which bind with the substrate forming the enzyme-subtrate complex so primary structure is important. secondary and tertiary structure is important for the sake of bonds holding the enzyme molecule in the shape that leads to formation of active site. Quaternary structure is important in the cases when two or more polypeptide chains are associated to form a active site .
hope my answer helped u

 

[sarahnafea]

As the active site is specific for each substrate this is possible due to r-groups of the amino acids which bind with the substrate forming the enzyme-subtrate complex so primary structure is important. secondary and tertiary structure is important for the sake of bonds holding the enzyme molecule in the shape that leads to formation of active site. Quaternary structure is important in the cases when two or more polypeptide chains are associated to form a active site .
hope my answer helped u

Thanks you, yes that helped. I was just confused because I've never heard of a 'quaternary' enzyme but I guess there is such a thing. =)