Lets revise guys, time is short :)

[XPFMember]

well did you do he human vascular things? the one about veins and arteries? And By the way:

Bio practical is a piece of cake trust me, if you did what you had to do and studied and blah blah blah, then you have nothing to fear

aoa wr wb!
what? biopractical? piece of cake? I'd score above 35 in chem n phys alhumdulilah, but bio...don't ask..it's always been in 20's
if u really think it's that easy, then do help me with it..

 

[Just call me MJ]

Well it all depends on what other subjects are you taking?!

 

[Just call me MJ]

aoa wr wb!
what? biopractical? piece of cake? I'd score above 35 in chem n phys alhumdulilah, but bio...don't ask..it's always been in 20's
if u really think it's that easy, then do help me with it..

So Which part exactly do you need help at?!?

 

[XPFMember]

So Which part exactly do you need help at?!?

i dont know i dont know but it's like i always mess it up ..as whole..

 

[rz123]

well then u shud clean the mess after doing practical. good luck!

 

[XPFMember]

well then u shud clean the mess after doing practical. good luck!

 

[Just call me MJ]

i dont know i dont know but it's like i always mess it up ..as whole..

This problem often involves calculations?!?
Or does it involve results?!?
Or does it involve writing, as in memorizing?

 

[XPFMember]

This problem often involves calculations?!?
Or does it involve results?!?
Or does it involve writing, as in memorizing?

nahnot calculations...
but the other two...

 

[ismailmz]

well as Just call me MJ has mentioned the figures that are required should only be learned, one thing I would suggest u is u need to have theoretical knowledge , like the structure of vein in the book... ones u get a slide u can identify easily wat structure to draw...

 

[ismailmz]

ho

I'll start with the first organelle " Nucleus"
Its the largest organelle in the cell, surrounded by a two layer membrane "Envelope" called the nuclear envelope. The outer membrane of the nuclear envelope is continuous with the rough endoplasmic reticulum .
The nuclear envelope is conspicuously perforated by holes known as Nuclear pores. These allow the exchange between the nucleus and the Cytoplasm, e.g Ribosomes and RNA from the nucleus to the cytoplasm, and hormones and nutrients from the cytoplasm to the nucleus. In the nucleus the chromosomes are in a loosely coiled state ( except during cell division, they turn into Chromatin ) .
The chromosomes contain DNA, which are organised into the functional units called genes. Genes control the activity of the cell and thus the Nucleus controls the cell's activities.
In the nucleus, The nucleolus, manufactures Ribosomes.

Remember Guys, Only from your head!!

why does nucleolus produce ribosome and what are the reasons for it ?

centrioles
As i know there are 2 centrioles outside the nucleus and are formed from microtubules, but here comes a QUESTION WHAT IS MICROTUBULES? PLEASE EXPLAIN ....

 

[ismailmz]

WHAT ARE THE THINGS WE HAVE TO KNOW FROM CELL MEMBRANE AND TRANSPORT PLEASE?

 

[ismailmz]

Very soon I will be starting with chemistry revision

Chapters : Hydrocarbon, Halogen Derivatives, Hydroxyl Compounds

And discuss with you guys so stay in touch everyone

 

[Just call me MJ]

ho
why does nucleolus produce ribosome and what are the reasons for it ?

centrioles
As i know there are 2 centrioles outside the nucleus and are formed from microtubules, but here comes a QUESTION WHAT IS MICROTUBULES? PLEASE EXPLAIN ....

to answer your 1st question, all you have to do is know what are ribosomes and what are their function. your question needs rephrasing.

ribosomes are tiny organelles that are produced by the nucleolus. they are found lying either free in the cytoplasm, or attached to endoplasmic reticulum.
they are about 22 nm in diameter, surrounded by a single layer membrane. their function is to synthesize proteins. they do that by translation of the mRNA produced from the nucleus.

microtubules are scaffoldings made from proteins. thats all you need to know for now


hope this helps

 

[Just call me MJ]

WHAT ARE THE THINGS WE HAVE TO KNOW FROM CELL MEMBRANE AND TRANSPORT PLEASE?

you have to know the structure of the cell membrane, the function of each tiny bit of molecule in the membrane, how the structure relates to the function of each molecule.( except for cholesterol).

about transport, you have to know diffusion, facilitated diffusion, active transport, exocytosis, andocytosis and osmosis.
you have to knoe the definition of each, an example of each, and the factors affecting each process.

did I answer your question?

 

[Just call me MJ]

nahnot calculations...
but the other two...

well, in this case, you have to go back to the book.
Its like ismailmz said, you need theoretical knowledge.
you also need to understand the question and know the results before you apply the practical. this also come from theoretical knowledge.
you also need to be very specific, for the questions might be tricky, the are not the same. there is always a twist, so read the questions carefully and do not hesitate.
example, when you analyze enzyme rate of reaction on starch, you have to know before you do the practical that the solution will turn from black '' after applying Iodine in Iodine solution" to colorless.
when do you have to stop the watch depends on the question, some questions say, when the solution completely turns colorless. some say when the solution starts turning colorless.
did that help?

 

[ismailmz]

Very soon I will be starting with chemistry revision

Chapters : Hydrocarbon, Halogen Derivatives, Hydroxyl Compounds

And discuss with you guys so stay in touch everyone

Ahh i forgot to include Introduction to organic chemistry...

Introduction to organic chemistry:

All carbon containing compounds are not oraganic, the ones with carbon and hydrogen only are organc compunds



Empirical formula: this is the simplest ratio of atoms present in the molecule ... eg- CH3 OR C2H5
Molecular formula : well this is a bit different from empirical here it give the actual number of each typpe of atom...
#To find molecular formula what we to do is take the empirical formula say CH2. Relative molecular mass of propene is 42. And CH2 has a Relative molecular mass of 14 so 42/14 =3 ie 3* CH2= C3H6 (easy).
Structural formula: As you all know it shows the bonds with carbon atoms. eg CH2-CH2
Displayed Formula: This is the 2D representation of the molecule.

 

[ismailmz]

WELL I STIL HAVE PROBLEM IN UNDERSTANDING SIGMA AND PIE BOND.... SO PLEASE HELP ME WITH THIS..

 

[ismailmz]

There are many other things in Introduction to Organic Chemistry.. I will discuss them later

Hydrocarbon

Alkane
1. Used as Crude Oil
2. Saturated Hydrocarbon because its has single bond
3. General Formula - CnH2+2
4. Tetrahedral in shape.

Physical properties

1. Boiling point increases as the number of carbon atom increases, because of greater intermolecular forces of attraction.
2. Straight chains have large surface area and so giving a greater molecular attraction.
3. Branched chains are compact and have less intermolecular attraction.
4. The less the intermolecular force of attraction the less is the boiling point.