F215 - Revision thread 13th June 2011

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^That was just an example. So if I basically go over the specification should I be fine? I really want to skip other stuffs from my book 'Ocr Heinemann' because there are a lot of things to learn but I really dont have time for it :redface:

As long as you have a good understanding of the course in general (ie. know how exnzymes work, biological molecules etc) then you would be fine just covering everything on the specification. A lot of this module is synoptic though, so it is important you know that other stuff.

Reply 421

Dunn0

Can someone please help explain what exactly we need to know about artifical selection of wheat?
Thanks

Reply 422

Waqar Y

Original post by J DOT A

Is a Homologous pair of chromosomes a bivalent? Or is it 2 maternal chromatids joined together at centromere?

Homologous pair of chromosomes = bivalent - this = the paternal and maternal chromosome.

Two chromatids are just called sister chromatids, it's one chromosome because the DNA replicates in interphase.

Reply 423

fortunecookie

When sections of DNA are put into BACS to create clone libraries. Is that basically a slower version of PCR?

Reply 424

India27

Hi guys! could someone help me with: Outlining the differences between reproductive and non-reproductive cloning?
I've come up with:
reproductive cloning is a a type of artificial cloning where organisms are formed that are genetically identical to another organism. Reproductive cloning can be useful for research purposes for scientist (when carrying out tests particular organisms), can be used by farmers to increase the number of organisms with the desirable characteristics, and also to produce plants and animal that are endangered or extinct to put back in their natural habitats.
Non-reproductive cloning (or therapeutic cloning) is a type of artificial cloning where embryonic stem cells are produced which are genetically identical to cells from another organism (stem cells harvested from young embryos). Can be developed into any type of cell. Scientists looking into producing tissue from stem cells to replace damaged tissue caused by a range of different genetic diseases.

This question on the specification is really vague (and so is my answer). Can anyone tell me if this information is enough? Or if you have any more information please help. Thanks :smile:

(edited 12 years ago)

Reply 425

kej817

Original post by India27

Hi guys! could someone help me with: Outlining the differences between reproductive and non-reproductive cloning?
I've come up with:
reproductive cloning is a a type of artificial cloning where organisms are formed that are genetically identical to another organism. Reproductive cloning can be useful for research purposes for scientist (when carrying out tests particular organisms), can be used by farmers to increase the number of organisms with the desirable characteristics, and also to produce plants and animal that are endangered or extinct to put back in their natural habitats.
Non-reproductive cloning (or therapeutic cloning) is a type of artificial cloning where embryonic stem cells are produced which are genetically identical to cells from another organism. Can be developed into any type of cell. Scientists looking into producing tissue from stem cells to replace damaged tissue caused by a range of different genetic diseases.

This question on the specification is really vague (and so is my answer). Can anyone tell me if this information is enough? Or if you have any more information please help. Thanks :smile:

Hi, in my notes I remember having something like:

reproductive cloning:
can be artificial or natural

artficial:
examples: artificial vegetative propagation/micropropagation, splitting embryos, nuclear transfer
Advantages: can clone high value animals in high numbers, rare animals cloned to preserve species, GM animals can be quickly reproduced, plants can be cloned with useful properties e.g. colour/taste/yield/disease and pest resistance
Disadvantages: chracteristics may have a negative effect on the animal's welfare, less genetic variety, long term health of animals hasn't really been researched into for clones

Natural:
Asexual reproduction e.g. basal sprouts
Advantages: Quick - so organisms can take advantage of environment's resources, can be completed if sexual reproduction isn't possible, all offspring have the genetic info to enable them to survive in the current environment
Disadvantages: less genetic variety so population may be vulnerable when there is a significant change e.g. new pathogen

Non-reproductive (aka therapeutic) cloning generates new cells/tissues/organs to replace those lost by damage. Advantages:
• Being genetically identical so no risk of being rejected as foreign
• Could end problems of waiting for a donor
• Can be used for any cell type as they are totipotent
• Less dangerous than a major operation
Some people object to its use in humans due to ethical objections to the use of human embryonic material and concerns about a lack of understanding of how cloned cells will behave over time.

Reply 426

India27

Original post by kej817

Thanks for that :smile:

really appreciated! +rep

Reply 427

slacker07906

We don't need the ads and disads. Also what do we need to know about selective breeding in wheat?

Reply 428

slacker07906

Right. Homeotic genes are similar in plants, animal and fungi. These genes control the development of body plans and bind to specific patterns at particular stages of development depending on when they are activated. Homeobox genes are length of DNA coding for around 60 amino acids. Homeobox genes are found in most if not all eukaryotes. This region binds to DNA to regulate transcription. In animals, the homeobox genes are concerned with the devlopment of body plans such as segmentation, the establishment of the anterior-posterior axis and activation of genes which code for body parts such as limbs.

Anything else I need to know?

Reply 429

greenford

can anybody explain to me interaction between gene loci...something i really dont get and also dominant and recessive epistais...

thanks

Reply 430

starburst92

What synoptic content do people think we'll need to know?

Reply 431

Dunn0

Can someone please help explain what exactly we need to know about artifical selection of wheat?
Thanks

Reply 432

Nirgilis

Maaaaan!

Has anyone done the January F215 paper part of their revision yet? .. It's a :devil:

of a test. 68% translated to 109 UMS (if the scale's linear) :s-smilie:

(edited 12 years ago)

Reply 433

slacker07906

What are the chances of hardy weinberg coming up and how many marks? Because I can't do it!!b

Reply 434

wrench22

Original post by starburst92

What synoptic content do people think we'll need to know?

all of it, that's what synoptic means.

Reply 435

starburst92

Original post by wrench22

all of it, that's what synoptic means.

But don't they usually ask synoptic questions linked with the unit 5 questions? They wouldn't just randomly have a whole questions on something that was in unit 2 by itself would they?

Reply 436

nif1boy

Original post by starburst92

What synoptic content do people think we'll need to know?

The module we did at the end of last year, the last chapter in this about biodiversity is well worth refreshing your mind on.

Reply 437

nif1boy

Is it bad to right lots of answers for 1 question. 8 mark questions i right 13 points because im not sure if some of them are right or wrong. Is that baaaddd???????????????????

Reply 438

jakehartley123

Original post by Kidms001

Maaaaan!

Has anyone done the January F215 paper part of their revision yet? .. It's a :devil:

of a test. 68% translated to 109 UMS (if the scale's linear) :s-smilie:

No idea how you ended up with this figure...
68% raw would be 130+ UMS going by http://www.ocr.org.uk/download/admin/ocr_56047_admin_unit_level_raw_mark.pdf

Or perhaps you meant 68% UMS? In which case;
150/100 = 1.5
1.5*68 = 102 UMS

:iiam: