Question

@nopen

Answer 1

Oh miss @nopen :P

Answer 2

here

Answer 3

Ok where do we start?

Answer 4

alright so I see A1 saying "I understand how DNA contains the instructions for forming species characteristics in the form of proteins."

I have to make a question out of this?

Answer 5

hmm i think it will be hard to make a question outta that :/ can we just keep it as is and then just explain what it means T_T is the like the AGCT thingy?

Answer 6

Ok do you know what translation and transcription mean?

Answer 7

Translation is when Mrna does something :/ not sure....

Answer 8

oh okay we have a long long road ahead of us lol

Answer 9

basically the DNA contains 4 bases
can you name them?

Answer 10

Adenine, Thymine , Cytosine , and Guanine

Answer 11

good so the sequence of those bases are what determines the characteristics of the protein

so they way how you can form a question for this could be..

What part of the DNA contains the instructions for forming proteins of respected characteristics?

Answer 12

confusing O-o

Answer 13

mmm what part do you find this confusing? lemme see if I can simply it further for you then :)

Answer 14

Wait so the answer to then questions were the bases?

Answer 15

yup :D

Answer 16

Oh LOL nvm then xD

Answer 17

haha I don't why I can copy past on OS but you can do it for me copy the question and the answer for it will be the part where I say "so the sequences of those bases...etc etc

Answer 18

*can't

Answer 19

This?

I can distinguish between DNA, genes, and chromosomes.

Answer 20

no no no lol I mean what I posted here on OS just now

Answer 21

Q.) What part of the DNA contains the instruction for forming protein with their respected characteristics?

Answer: The Sequences of the four bases are what determines the characteristics of the proteins

Answer 22

that's what I wanted you to do lol ^^

Answer 23

Done :P

Answer 24

"
I can distinguish between DNA, genes, and chromosomes."
thats next :/

Answer 25

yeah just a sec for this I cannot attach a pic I have to find the most appropriate way to describe it

Answer 26

so basically the DNA is a long strip of nucleotides and the backbone of the nucleotides are the posphate-sugar backbone

http://knowgenetics.org/wp-content/uploads/2012/12/Bio-1-e1354321656394.png

Answer 27

the DNA is wrapped around something called histones, and there are about 8 of them (them meaning the histones) they are further bend to form nucleosomes and that is further bend to form chromosomes

Answer 28

I'm trying to find the most simple looking pic as possible
http://www.abcam.com/cms/displayImage.cfm?intImageID=4228

Answer 29

the octamers are just another way of saying 8 histones

Answer 30

O_O i have never learned about the stones

Answer 31

oh...oops

Answer 32

XD this is all soo confusing >_<

Answer 33

oh okay I'm gonna try my best to use a simple analogy

imagine you have a string (and consider that string as the DNA) now imagine you are wrapping those DNA 'strings' around 8 marbles (imagine the marbles being histones)

you will start seeing these beads-like structure if you bend that further it will become like a tight rope and that rope in the end is all tangled up and packed in a X-like looking suitcase now thats what your chromosome looks like in the end

Answer 34

Makes more sense now :)
string = DNA
Marbles = stone

Answer 35

histones lol
yup xD

Answer 36

:P

Answer 37

look at that pic it's much more simpler

Answer 38

O_o no its not :/

Answer 39

ignore the left hand side they are just talking about the strings and marble part

look from the nucleosomes onwards that's the rope part forming into this huge tangle

Answer 40

hmmm :/

Answer 41

did you get the rope part?

Answer 42

it kinda makes sense

Answer 43

okay I think it's a little too deep which I think is not required of that depth of explanation
because there are more stuffs like the linker regions and scaffolding proteins and such


just remember in this sequence

DNA double helix-----> Nucleosomes fibre------> Solenoid fibre------>coiled solenoid fibre-------> Supercoiling-------> Chromosomes

Don't freak out, they are just using fancy for wrapping the DNA like a sandwich XD

Answer 44

just match the names with the picture I attached
just see the names on the pic

Answer 45

*fancy word lol

Answer 46

Nucleosome fibers are nothing but the strings and marble part

Answer 47

ok it makes sense now :-)

Answer 48

really? cool

Next part
I understand how the nucleotides (A,T, G, & C) are the instructions for making the proteins that make our bodies and cells work.

do you know how transcription works?

Answer 49

nope

Answer 50

Okay.
mmm (I'm thinking how do I start with this xD)

Answer 51

do you know why the DNA is called the double helix?

Answer 52

it has two strands

Answer 53

they care called double helix because of that 'twist' that you see in the DNA

Answer 54

right....

Answer 55

okay so you wanna make protein out of this and you need the information of base sequence

you have to unwind the dna right?

Answer 56

yes

Answer 57

there is a certain enzyme to open it up and it's called the helicase

Answer 58

isnt it dna polymerse

Answer 59

Polymerase has a different purpose. (It's mostly used in DNA replication)
it's Helicase that unwinds the DNA and after that the two strands are seperated and then they are exposed to be used as a template by the mRNA

Answer 60

there are Free activated RNA nucleotides laying around in the nucleus and THEN the activated RNA nucleotids are attached by Polymerase (like a glue)

Answer 61

ofc the RNA nucleotides are gonna be complementory to the original DNA

Answer 62

hmm :/ rna replaces thymine though with uracil

Answer 63

Oh yes correct I forgot to mention about that
so this is mainly the transcription part

Answer 64

next is the transcription part

Answer 65

do you know how a tRNA looks like?

Answer 66

nope

Answer 67

this is really strange..
how come they are asking questions from topics that you guys haven't covered? :/

Answer 68

We prbably have but this was at the beggening of the semster

Answer 69

So i dont remeber it much :/

Answer 70

And we didnt really have any notes to take .-.

Answer 71

Alright, I will write the answers for this then.

Proteins are made from a process called 'protein synthesis' which can be divided into two parts

Transcription and Translations
Transcription is part where mRNA are made using one of the DNA strands as a Template, that mRNA travels through the Nuclear pore to the Ribosomes, from here on Translations starts as the Ribosomes holds the mRNA in place and the tRNA comes in with the 3 Complementory anticodons with their respected amino-acids attached to them

the amino acids are attached by peptide bonds and forms a chain of amino acids

Answer 72

Ooo ok :-) this makes more sense :D i actually get it nao :D

Answer 73

what is the deadline for this?

Answer 74

*when

Answer 75

This is a study guide :) i ahve one week to study for finals

Answer 76

@Abhisar
help me with gene expressions ;_;

Answer 77

LOL

Answer 78

hmm >.>

Answer 79

I know A level bio so gene expression is limited for me
I can article and reply but it's gonna take me some time

http://www.garlandscience.com/res/pdf/9780815341291_ch08.pdf

Answer 80

*read

Answer 81

Lets continue tommrow or maybe later? :) And i will read the article too :)

Answer 82

no no no don't post it there LOL

post my answer in the previous question

Answer 83

the one with the A T G C

Answer 84

oops XD

Answer 85

yup
now it's alright xD

Answer 86

:) ok thanks for the help! :)

Answer 87

no problem, lemme read some stuff and I will come back to this post to answer it.

Answer 88

okie

Answer 89

for A4
To answer this more appropriately, it's basically control of gene expression

Cell differentiation is what causes the gene expression to be controlled, it can be controlled in many ways for example there can be structural alteration such as modifications of Nucleosomes which can change the amount of supercoiling, which further affects the frequency of transcriptions of such areas of the chromatins

there are other means too like Methylation of DNA or Histone acetylation

Methylation is a way of slicing the DNA, and . Histone acetyltransferase enzyme dissociate the DNA from the histone complex, allowing transcription to proceed

so and so forth

Answer 90

@pooja195
it'd be really nice if you can post the pics of the topic of A4 from your book as well as epigenetics chapter

Answer 91

I can explain how all cells contain the entire genome of an organism but that only specific genes are switched on or off depending on the type of cell.

Answer 92

^A4