Author Topic: CHEM AND BIO HELP AND TIPS HERE  (Read 333105 times)

Offline princess12

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1725 on: May 23, 2010, 07:40:55 pm »
thanxs
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Offline Ivo

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1726 on: May 23, 2010, 07:41:16 pm »
'list the main features used in the classification of the following groups: viruses, bacteria and fungi, and their adaptation to the environment, as appropriate'

im not really sure about this part, could any1 pls correct me if im wrong n add details if possible? thx

virus:
-protein coat
-DNA/RNA strand
-presence of lipids

bacteria:
-plasmid
-no nucleus

fungi:
-cell wall made out of chitin
-hyphae, used to absorb nutrients(is it always from dead organic matters?)

Bacteria also have flagellum, which helps movement of bacteria.

Fungi, talk about spores being produced for reproduction as well.
Always willing to help!  8)
"In helping others, we shall help ourselves, for whatever good we give out completes the circle and comes back to us."

Offline someone

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1727 on: May 23, 2010, 07:42:26 pm »
can i tell u chemistry this question
find the empirical formula when 0.5g of H was found to combine with 4.0g of O to form water
can any 1 explain me
urgently reply me as fast as u can
thanks in avance
 :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( ??? ??? ??? ??? ??? :'( :'( :'( :'(

divide atomic mass with each mass given in the question for each atom:

Oxygen: 16/4 = 4
Hydrogen: 1/0.5 = 2

then find the proportion of the two values:

hydrogen : oxygen =
4 : 2 =
2 : 1

therefore, theres 2 hydrogen and 1 oxygen, the formula becomes H2O

oops, already answered :P
« Last Edit: May 23, 2010, 07:44:02 pm by someone »

Offline princess12

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1728 on: May 23, 2010, 07:44:37 pm »
no problem
thanks
We should be kind to after teachers

Offline Ivo

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1729 on: May 23, 2010, 07:44:52 pm »
divide atomic mass with each mass given in the question for each atom:

Oxygen: 16/4 = 4
Hydrogen: 1/0.5 = 2

then find the proportion of the two values:

hydrogen : oxygen =
4 : 2 =
2 : 1

therefore, theres 2 hydrogen and 1 oxygen, the formula becomes H2O

oops, already answered :P

Oh well, at least it's good practice - trying to help others always has its benefits ;D!
Always willing to help!  8)
"In helping others, we shall help ourselves, for whatever good we give out completes the circle and comes back to us."

Offline princess12

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1730 on: May 23, 2010, 07:46:17 pm »
yes u r right
We should be kind to after teachers

Offline Helium

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1731 on: May 23, 2010, 07:47:46 pm »
 Is the chat room always empty ???
 ;D
Aiming for the top

Offline Ivo

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1732 on: May 23, 2010, 07:48:42 pm »
Is the chat room always empty ???
 ;D

Now it's not! :D
Always willing to help!  8)
"In helping others, we shall help ourselves, for whatever good we give out completes the circle and comes back to us."

Offline someone

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1733 on: May 23, 2010, 07:49:21 pm »
'describe translocation throughout the plant of applied chemicals, including systemic pesticides'

can any1 help me with this? is the translocation occur in the same way with the translocation of nutrients? thx

Offline thenewkid™

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1734 on: May 23, 2010, 07:49:32 pm »
ok guys gonna get some sleep its 11pm here and i hv to be at school by 8am (bus comes at 6:30am)

may Allah help us all
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Offline ambitious94

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1735 on: May 23, 2010, 07:50:04 pm »
Heyy, can anyone please answer this question: Describe what happens in the soil to convert dead plant material into nitrate ions that
plants can absorb.

how is ammonia converted to nitrites then nitrates?
Where does nitrifying bacteria come in? Can anyone clarify please?

Offline Ivo

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1736 on: May 23, 2010, 07:51:42 pm »
'describe translocation throughout the plant of applied chemicals, including systemic pesticides'

can any1 help me with this? is the translocation occur in the same way with the translocation of nutrients? thx

Systemic pesticides are sprayed on the crop plants which absorb them.  The pesticides are translocated to all parts of the plant in the phloem.  Any insect feeding on any part of the plant will ingest the pesticide with the plant tissue.  After a while the insect will ingest enough to kill it.  The same happens to fungi growing on or inside any part of a crop plant.

Hope that helps ;)!
Always willing to help!  8)
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Offline someone

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1737 on: May 23, 2010, 07:53:05 pm »
Heyy, can anyone please answer this question: Describe what happens in the soil to convert dead plant material into nitrate ions that
plants can absorb.

how is ammonia converted to nitrites then nitrates?
Where does nitrifying bacteria come in? Can anyone clarify please?

when dead plants decompose, ammonia from dead plants goes to soil
the nitrifying bacteria converts ammonia to nitrate

pls correct me if im wrong, thx :)

Offline Ivo

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1738 on: May 23, 2010, 07:53:34 pm »
Heyy, can anyone please answer this question: Describe what happens in the soil to convert dead plant material into nitrate ions that
plants can absorb.

how is ammonia converted to nitrites then nitrates?
Where does nitrifying bacteria come in? Can anyone clarify please?

Answer to first question:

The dead plant material is subject to decay by decomposing bactera.  These bacteria convert amino acids into ammonia (deamination).  The nitrifying bactera in the soil convert this ammonia into nitrite, then from nitrite into nitrate in the soil.  The plants are then able to absrob these nitrates in the soil.  

That's my model answer to the question.  Hope that helps :)
Always willing to help!  8)
"In helping others, we shall help ourselves, for whatever good we give out completes the circle and comes back to us."

Offline ambitious94

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1739 on: May 23, 2010, 07:56:30 pm »
Answer to first question:

The dead plant material is subject to decay by decomposing bactera.  These bacteria convert amino acids into ammonia (deamination).  The nitrifying bactera in the soil convert this ammonia into nitrite, then from nitrite into nitrate in the soil.  The plants are then able to absrob these nitrates in the soil.  

That's my model answer to the question.  Hope that helps :)
Thanks. That's a rlly good answer :)
And 'someone' too...thanks!