This discussion is closed.
Gnome :)
Badges: 2
Rep:
?
#1441
Report 6 years ago
#1441
(Original post by AdamStott64)
I can't think of enough to write about for the essay:
"Why offspring produced by the same parents are different in appearance."
Feels more like a 3 marker to me! Any help guys?
Genetic: mutation (deletion, insertion, substitution), and the effect on transcrpition/translation/protein synthesis
Sexual reproduction:random fusion, crossing over, independent assortment, dominant and recessive alleles
Environment: effect of environment on switching genes on/off maybe? Taxis of plants?
0
AtomicMan
Badges: 12
Rep:
?
#1442
Report 6 years ago
#1442
(Original post by AdamStott64)
I can't think of enough to write about for the essay:
"Why offspring produced by the same parents are different in appearance."
Feels more like a 3 marker to me! Any help guys?
Can talk about Meiosis (unit 2) -> Leading to different genotypes/alleles between siblings (unit 4) -> Leading to different dna base sequence, so different sequence of amino acids in polypeptide (transcription/translation from unit 5) -> Leading to different protein structures (unit 1).

Could also mension stuff about mutations, and the advantages of genetic variation.
2
starfish232
Badges: 0
Rep:
?
#1443
Report 6 years ago
#1443
Are there any other topics to talk about for the essay question 'explain how surface area is linked to the transfer of substances within the body and between the body and the environment'?

I've so far got:
Gas exchange in insects and lungs
Photosynthesis - adaptations of leafs regarding surface area
Adsorption in small intestine
Xerophytes - adaptations to reduce SA to reduce water loss
Heat loss in humans
0
master y
Badges: 0
Rep:
?
#1444
Report 6 years ago
#1444
(Original post by starfish232)
Are there any other topics to talk about for the essay question 'explain how surface area is linked to the transfer of substances within the body and between the body and the environment'?

I've so far got:
Gas exchange in insects and lungs
Photosynthesis - adaptations of leafs regarding surface area
Adsorption in small intestine
Xerophytes - adaptations to reduce SA to reduce water loss
Heat loss in humans
surely xerophytes don't count as 'body'?


Also, has anyone done june 2011 paper? If so how did you find it, i just did it. There is a lot of synoptic stuff within the paper itself!
0
starfish232
Badges: 0
Rep:
?
#1445
Report 6 years ago
#1445
(Original post by master y)
surely xerophytes don't count as 'body'?


Also, has anyone done june 2011 paper? If so how did you find it, i just did it. There is a lot of synoptic stuff within the paper itself!
Why wouldn't they? Their still plants...can plants be included in this? I'm not really sure...
0
ahmmm
Badges: 0
Rep:
?
#1446
Report 6 years ago
#1446
Can anybody send me their essays? Struggling! :confused:
0
helpme456
Badges: 0
Rep:
?
#1447
Report 6 years ago
#1447
What is negative feedback?
0
Mocking_bird
Badges: 11
Rep:
?
#1448
Report 6 years ago
#1448
"How Bacteria Affect Human Lives" essay. 23/25.

Name:  Scan10009.jpg
Views: 1627
Size:  540.5 KB
Name:  Scan10010.jpg
Views: 1369
Size:  554.5 KB
Name:  Scan10012.jpg
Views: 1048
Size:  534.7 KB

If you can't read anything let me know, some people struggle with my handwriting alot :lol:
1
JoshL123
Badges: 2
Rep:
?
#1449
Report 6 years ago
#1449
(Original post by helpme456)
What is negative feedback?
Negative feedback refers to a control mechanism used to return something to the 'preset'/ original value. Examples of negative feedback mechanisms are evident in the controllinyg of blood glucose concentrations, cobtrolling of the core body temperature but alsothe relationships between LH and progesterone and FSH and oestrogen in the oestrous cycle
0
Castiel'
Badges: 0
Rep:
?
#1450
Report 6 years ago
#1450
(Original post by Beth_L_G)
I did the diseases and nitrogen ones under exam conditions. The rest I've done with books, the Internet and some random knowledge I've picked up over the last 19 years
Ah fair enough

(Original post by starfish232)
Hi could someone please explain how the desired gene put into bacterium are transferred to the organism that you want to possess the gene and express it?
1. Extract the plasmids containing the desired gene from the bacteria
2. Wrap these plasmids in liposomes (liposomes are used since they're made up of lipids meaning they can cross the phospholipid bilayer of the cell easily)
3. Spray the liposomes as an aerosol into the nostrils of human (similar for other organisms). [an aerosol is basically a fine spray]

The liposomes will enter the target cells e.g. Epithelial cells and the desired gene will be expressed since the gene is associated with the target cells' function.
0
starfish232
Badges: 0
Rep:
?
#1451
Report 6 years ago
#1451
(Original post by Castiel')
Ah fair enough



1. Extract the plasmids containing the desired gene from the bacteria
2. Wrap these plasmids in liposomes (liposomes are used since they're made up of lipids meaning they can cross the phospholipid bilayer of the cell easily)
3. Spray the liposomes as an aerosol into the nostrils of human (similar for other organisms). [an aerosol is basically a fine spray]

The liposomes will enter the target cells e.g. Epithelial cells and the desired gene will be expressed since the gene is associated with the target cells' function.
What about if you wanted to do it in a plant? Like for example in producing genetically modified crops
0
master y
Badges: 0
Rep:
?
#1452
Report 6 years ago
#1452
How does the DNA probe actually check for a mutated gene... is the base sequence complementary to the mutated gene so it glows when it is mutated, or is it complementary to the normal gene, so it doesn't glow if it is mutated?

(Original post by Castiel')
.

(Original post by Mocking_bird)
.:
0
Mocking_bird
Badges: 11
Rep:
?
#1453
Report 6 years ago
#1453
(Original post by master y)
How does the DNA probe actually check for a mutated gene... is the base sequence complementary to the mutated gene so it glows when it is mutated, or is it complementary to the normal gene, so it doesn't glow if it is mutated?
When you add the DNA probe, if the gene you're looking for is present it will attach to it due to it being complimentary.
So when you wash it, it'll remove the unattached probe, so then you can detect the presence of the probe by autoradiography or the fluoresce it emits.

So basically, if the gene isnt there, you won't see anything because the probe will not have attached.
0
master y
Badges: 0
Rep:
?
#1454
Report 6 years ago
#1454
(Original post by Mocking_bird)
When you add the DNA probe, if the gene you're looking for is present it will attach to it due to it being complimentary.
So when you wash it, it'll remove the unattached probe, so then you can detect the presence of the probe by autoradiography or the fluoresce it emits.

So basically, if the gene isnt there, you won't see anything because the probe will not have attached.
I might sound really stupid but doesn't everyone have the same genes, its just the alleles which are different and if the genes are expressed? Also doesn't everyone have a tumour suppressor gene but not everyone has the mutated suppressor gene... so will the probe look for the mutated gene?/ :L
0
master y
Badges: 0
Rep:
?
#1455
Report 6 years ago
#1455
Is anyone willing to mark my essay if i send it to them? (DNA in science and technology)
0
Mocking_bird
Badges: 11
Rep:
?
#1456
Report 6 years ago
#1456
(Original post by master y)
I might sound really stupid but doesn't everyone have the same genes, its just the alleles which are different and if the genes are expressed? Also doesn't everyone have a tumour suppressor gene but not everyone has the mutated suppressor gene... so will the probe look for the mutated gene?/ :L

The probe is used to screen patients for a mutated gene.
You're confusing me with what you're asking.
0
candyhearts
Badges: 0
Rep:
?
#1457
Report 6 years ago
#1457
(Original post by Mocking_bird)
"How Bacteria Affect Human Lives" essay. 23/25.


If you can't read anything let me know, some people struggle with my handwriting alot :lol:
Did you write that under exam conditions? Also, I've been doing really simple spider diagrams for my plans but for someone such as myself who will not finish their essay in time, would you recommend a more in depth plan?
0
AdamStott64
Badges: 7
Rep:
?
#1458
Report 6 years ago
#1458
Right just looked at the essay "How the structure of cells is related to their fuction"

I've not written the essay I've sort of just planned it all out.

Anybody think of anything else to add?



Thought I'd open by talking about gene expression and cell differentiation. And then say how tissues are sheets of identical cells which are efficient at one function and the body works in systems to allow cells to reply on each other (put and example in... (Muscle cells reliant on alveoli to supply O2))

Then how distribution of organelles is different between cells. Red blood cells have even lost their nucleus for space for oxygen.

Examples of cells which have abundance is a certain organelles. Golgi and mitochondria in synapses to produce neurotransmitter (go into detail about acetyl choline ect?)

Right... Plants... Palisade cells have a vacuole which pushes chloroplast to the surface to expose against light, chloroplast organised for maximum surface area... Also have cell walls so they don't bust during contact with nearly pure water in soil. They become turgid

Fast twitch muscles - loads of phosphocreatine and anaerobic enzymes
Slow twitch -high blood supply and mitochondria for aerobic respiration
Also muscles are fused together and share sarcoplasm for increase strength. Many fibres (like a rope).

Also about intestine epithelial cells (microvilli) to increases surface area and can also talk about sodium glucose pump.

Squamous alveoli.... Ficks law!


Posted from TSR Mobile
0
Mocking_bird
Badges: 11
Rep:
?
#1459
Report 6 years ago
#1459
(Original post by candyhearts)
Did you write that under exam conditions? Also, I've been doing really simple spider diagrams for my plans but for someone such as myself who will not finish their essay in time, would you recommend a more in depth plan?
Yep, was in the mock that we did.

But yeah, either that or you can just bullet point at the end.
But if you know you won't finish it, why don't you just work on your timings before the exam so you dont have to deal with that problem? :P
0
darryalar
Badges: 11
Rep:
?
#1460
Report 6 years ago
#1460
Can someone please help with unit 4 as im really struggling. These how science works questions are killing me.

Why can't i access this thread http://www.thestudentroom.co.uk/show....php?t=2134026
I really need to as there's some good notes in there.
1
X
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

University open days

  • Cardiff Metropolitan University
    Undergraduate Open Day - Llandaff Campus Undergraduate
    Sat, 19 Oct '19
  • Coventry University
    Undergraduate Open Day Undergraduate
    Sat, 19 Oct '19
  • University of Birmingham
    Undergraduate Open Day Undergraduate
    Sat, 19 Oct '19

Why wouldn't you turn to teachers if you were being bullied?

They might tell my parents (23)
6.74%
They might tell the bully (33)
9.68%
I don't think they'd understand (52)
15.25%
It might lead to more bullying (131)
38.42%
There's nothing they could do (102)
29.91%

Watched Threads

View All