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Kujah

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dolbinau said:
For Physical Environment, Chemical Environment and Competition of resources in affecting evolution; do we need to know specific examples of animals or can we generalise?
Specific examples.
 

Bobbles22

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dolbinau said:
For Physical Environment, Chemical Environment and Competition of resources in affecting evolution; do we need to know specific examples of animals or can we generalise?
I don't think they would specify, but its best to know.

Explain why the processes of diffusion and osmosis are inadequate in removing dissolved nitrogenous wastes in some organisms.
 
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midifile

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Bobbles22 said:
Describe current theories about processes responsible for the movement of materials through plants in xylem and phloem tissue.
Someones already done xylem a few questions above so i cbf doing it again

Phloem - The current theory is known as the mass flow theory (or bulk flow theory) Sucrose in solution moves in the phloem by translocation either up or down the plant. At a sugar source (photosynthetic cell), sucrose in solution moves into the seive tube cell. This increases sugar concentration in this cells, so water moves from the xylem adjacent to this cell by osmosis. This increases the pressure at the source. At a sugar sink (where sugar will either be used in respiration or stored) suger moves out of the sieve tube cell. This decreases sugar concentration in the phloem, so water moves out of the phloem to the xylem by osmosis. This decreases pressure at the sink. As a result, sucrose in solution will always move from source to sink (which may either be up or down the plant).
 

midifile

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Bobbles22 said:
I don't think they would specify, but its best to know.

Explain why the processes of diffusion and osmosis are inadequate in removing dissolved nitrogenous wastes in some organisms.
Osmosis only refers to the movement of water across a membrane, so would not remove nitrogenous wastes.

Diffusion will only occur when the concentration of nitrogenous wastes is greater in the blood than in the filtrate (as nitrogenous wastes move from a high to a low concentration with the gradient). As a result diffusion would only occur until the concentration of nitrogenous wastes are equal in the blood and filtrate, and would not completely remove wastes.

Rather, pressure filtration is used in bowmans capsule to remove wastes
 
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Kujah

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And diffusion is too slow and only relies upon the random movement of particles.
 

Kujah

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Takuto said:
this is the best thread ever :D
Haha, yeah, I love this thread... great and useful information! And really good for revising :D

Q: Discuss the evidence for the mutagenic nature of radiation.
 

tau281290

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Who are all the crazy biologists we need to know?

1. Boveri
2. Sutton
3. Morgan
4. Mendel
5. Beadle
6. Tatum
7. Darwin
8. Lamarck
9. MacFarlane
10. James Watson, Francis Crick, Rosalind Franklin, Maurice Wilkins
11. Pasteur
12. Koch

WHO ELSE? Remind me thx.
 

dolbinau

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Is Lamarck part of the historical development of Evolution? What other things do we have to know under this header? (It's not specified under the syllabus I don't think, unless it's part of an option)
 

midifile

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Theres also gould and eldrigde - they came up with punctuated equilibrium (although Im not sure if we have to know their names as they are not mentioned in the syllabus, although punctuated equilibrium is)
 

tau281290

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Lamarck is the failure dude who thought animals would "lose" some parts of those organs if they don't use it. Your answers in Darwinian theories must NOT contain any Lamarckian ideas otherwise you will lose marks.
 

midifile

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Does anyone know exactly how much we need to know about macfarlane? There isnt really anything specific on him in the syllabus, they just mention his name, so do we just have to know that he contributed to understanding about the immune respones
 

Kujah

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midifile said:
Does anyone know exactly how much we need to know about macfarlane? There isnt really anything specific on him in the syllabus, they just mention his name, so do we just have to know that he contributed to understanding about the immune respones
I guess you can talk about him and his clonal selection theory, or how he made a vaccination for influenza. Thats all I guess.

And the scientists involved with malaria for the list.
 

tau281290

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Probably just one line about MacFarlane in case they ask in the MC? Do you think they will ask about him in short answers?
 

Bobbles22

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midifile said:
Does anyone know exactly how much we need to know about macfarlane? There isnt really anything specific on him in the syllabus, they just mention his name, so do we just have to know that he contributed to understanding about the immune respones
Ive only seen a multiple choice question on him, but he doesnt really come up in the sybllabus, just a quick overview in the focus area
 

tau281290

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Who are all the crazy biologists we need to know?

1. Boveri
2. Sutton
3. Morgan
4. Mendel
5. Beadle
6. Tatum
7. Darwin
8. Lamarck
9. MacFarlane
10. James Watson, Francis Crick, Rosalind Franklin, Maurice Wilkins
11. Pasteur
12. Koch

Malaria guys:

13. – 1880: Laveran observed micro-organisms in fresh blood from malarial patients and suggested that malaria was caused by this micro-organisms

14. – 1886: Golgi observed asexual reproduction of microbe in blood of patients

15. – 1894: Patrick Manson proposed that malaria is transmitted by mosquitoes

16. – 1898: Grassi discovered that malaria was transmitted by the Anopheles mosquito

17. – 1897-1899: Ronald Ross established that the protozoan Plasmodium was the cause of malaria, winning the Nobel Prize.

Anyone else? Remind me thx.
 
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dolbinau

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Thankyou. But God. Have you remembered the historical development of Malaria off by heart :p?
 

Bobbles22

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tau281290 said:
Probably just one line about MacFarlane in case they ask in the MC? Do you think they will ask about him in short answers?
Theres nothing they can really ask about him. its something people learn even though its not heavly in the syllabus as with incomplete dominance etc
 

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