The Student Room Group

Scroll to see replies

Reply 440
Just thought it would be a good idea to get some predictions going of what possibly could come up? Just to give everyone a heads up on stuff that they might need to just go over quickly to make sure that it's fresh. :smile:
Original post by RyanMarshall94
Are disulfide bonds always double bonds?

Posted from TSR Mobile


All you need to know is that they're very strong covalent bonds. That's all...
Original post by cab1094
Just thought it would be a good idea to get some predictions going of what possibly could come up? Just to give everyone a heads up on stuff that they might need to just go over quickly to make sure that it's fresh. :smile:


- Cellulose
- Vaccination
- CHD
- Emulsion test
- Enzymes and pH
- Nicotine
- Darwin's observations (direct question i.e. what are they)
Reply 443
Original post by wndms
Oh thank you so much!
So for Alpha glucose, they have 1-4 glycosidic bond but they are not rotated 180' so it's coiled right?

Posted from TSR Mobile


Glycogen has alpha 1,4-glycosidic bonds, which form the main chains and 1,6-glycosidic bonds, which form the branches.
Anyone got the jan 2013 paper, can't be bothered looking through the pages haha :smile:.
Reply 445
Original post by wndms
Can anyone help me with this please?
You know how two alpha glucose makes maltose and more than two alpha glucose makes amylose.

How about beta glucose? What happens if two beta glucose join together? Is there a name for it?
Posted from TSR Mobile


I don't think we need to know. Just know that it'd be a disaccharide :smile:
Reply 446
Original post by Beni24
Wheres Disupfide bonds found?


In antibodies (disulfide bridges) which hold the polypeptide chains together.
In the tertiary structure of proteins, between two sulfur containing R groups.
Reply 447
Original post by RadioheadAnton
Is anyone bothering to remember all the trash in the last module? Like international cooperation. God its dull


Not really. It's the worst module ever. :frown:
Reply 448
how is influenza spread?
(edited 10 years ago)
Reply 449
Original post by wndms
Can anyone help me with this please?
You know how two alpha glucose makes maltose and more than two alpha glucose makes amylose.

How about beta glucose? What happens if two beta glucose join together? Is there a name for it?
Posted from TSR Mobile


no but many of these form together to make cellulose if that's what you mean
Reply 450
Original post by sylly
Can someone tell me about the three domains because I have no notes on it and text book doesn't give much info. Thanks!


There are 3 domains in total.
These are bacteria (eubacteria), archae (archaebacteria) and eukarya.
Domain classification is based on RNA polymerase, protein synthesis, membrane structure, etc.
All eukaryotes are in the same domain, which reflects the similarities between eukaryotic kingdoms. For example, all eukaryotes have nuclei and membrane bound organelles.
Prokaryotes are split into two different domains, which reflects the differences between bacteria and archea. For example, the differences between their cell walls and membranes.
This is all from two mark schemes :smile:
Reply 451
Original post by Beni24
Wheres Disupfide bonds found?


- Tertiary structure of a protein between Cysteine amino acids
- Between the heavy and light chain of antibodies
Reply 452
Original post by Giggles96
how is influenza spread?


I'd expect that to be a suggest question. Common sense; sneezing.
Original post by Giggles96
how is influenza spread?


Droplet Infection
Original post by jamesmact
Triglyceride - One glycerol and three fatty acids, contains three ester bonds, and mainly used for long term energy storage, insulation/protection of organs, form HDL and LDL's.

Phospholipid - one glycerol, one phosphate head, two fatty acids bonded to glycerol molecule by ester bonds. Composes plasma membrane of cells. It's important to remember that the tails are HYDROPHOBIC, and the head is HYDROPHILIC, hence why the bilayer forms in water.

Cholesterol - structure is always given, don't need to know about its structure, although its used to make hormones and steroids, as well as regulate fluidity of cell surface membranes, more cholesterol, the less fluid it is.


Posted from TSR Mobile


We need to know about why Cholesterol is classed as a lipid though. So technically yes the structure is needed. It forms benzene rings and only contains the elements C, H & O :smile:
The biodiversity and conservation module is so ****. I like the biological molecules stuff, but the last module, I cannot tolerate. Oh well, 3 days and it will be done, until next year
:banghead:

Anyway, questions anyone?
What is the difference between species richness and species evenness?
and
How does irradiation preserve food?
Reply 456
Original post by aaaarroonnn
The biodiversity and conservation module is so ****. I like the biological molecules stuff, but the last module, I cannot tolerate. Oh well, 3 days and it will be done, until next year
:banghead:

Anyway, questions anyone?
What is the difference between species richness and species evenness?
and
How does irradiation preserve food?


Species richness is the number of different species within a habitat.
Species evenness is the number of individuals within each species.
Irradiation destroys the DNA sequence of bacteria and so in turn, kills them.
Original post by aaaarroonnn
The biodiversity and conservation module is so ****. I like the biological molecules stuff, but the last module, I cannot tolerate. Oh well, 3 days and it will be done, until next year
:banghead:

Anyway, questions anyone?
What is the difference between species richness and species evenness?
and
How does irradiation preserve food?


Species richness is the number of different species in a habitat.
Species evenness is the population of each species when compared to each other.
e.g
a= 30
b= 30
c= 30
VERY EVEN.

Irridation uses gamma rays to mutate and change the DNA of the bacteria. Killing the microorganisms
Reply 458
Is it just me or is the OCR textbook useless? It exaggerates everything on the spec and every answer is like a paragraph long. The revision guide is also trash despite the fact that it says it is tailored to the spec when its clearly not.
(edited 10 years ago)
Reply 459
Original post by trrr
Is it just be or is the OCR textbook useless? It exaggerates everything on the spec and every answer is like a paragraph long. The revision guide is also trash despite the fact that it says it is tailored to the spec when its clearly not.


Yeah, it's not very good for this unit. Even things like definitions, if you write some exactly from the book they won't always get you the marks. Which is why I've been learning them from mark schemes instead.

Latest

Trending

Trending