Biology; Chemistry; Physics: Post your doubts here!

[Gémeaux]

Can any one help me with this MCQ???It is Biology Paper- ON 2008P1 Q12

the answer's D. this explains it better than any ov my attempts:
er: A complex question, in which candidates must first identify X as a xylem element and Y as a phloem
sieve tube. Testing their contents will show no reducing sugar or starch in the xylem or the phloem,
since sucrose (a non-reducing sugar) in the phloem will give a negative Benedict’s test unless
previously hydrolysed and then neutralised.

 

[hassan100]

the answer's D. this explains it better than any ov my attempts:
er: A complex question, in which candidates must first identify X as a xylem element and Y as a phloem
sieve tube. Testing their contents will show no reducing sugar or starch in the xylem or the phloem,
since sucrose (a non-reducing sugar) in the phloem will give a negative Benedict’s test unless
previously hydrolysed and then neutralised.

yes correct

 

[KumaiL JavaiD]

you mean examiner report?

Which Book Would You Recommend For This?

 

[snowbrood]

can anyone tell me how to remove yeast in fermentation process and why does limewater prevents air entering the apparatus in fermentation process

 

[snowbrood]

immediate help would be appreciated

 

[legion]

When fermentation has finished, the beer is cooled to about 32 F (0 C). This helps the remaining yeast settle to the bottom of the fermenter, along with other undesirable proteins that come out of solution at this lower temperature.
Now that most of the solids have settled to the bottom, the beer is slowly pumped from the fermenter and filtered to remove any remaining solids.
dunno about the other part. sorry

 

[snowbrood]

When fermentation has finished, the beer is cooled to about 32 F (0 C). This helps the remaining yeast settle to the bottom of the fermenter, along with other undesirable proteins that come out of solution at this lower temperature.
Now that most of the solids have settled to the bottom, the beer is slowly pumped from the fermenter and filtered to remove any remaining solids.
dunno about the other part. sorry

i thought yeast dies at the temperature above 37 degrees

 

[hassan100]

can anyone tell me how to remove yeast in fermentation process and why does limewater prevents air entering the apparatus in fermentation process

for the second part i think that limewater will form a precipitate of calcium carbonate so air will not enter the appratus
Still i am not sure ,correct me if i am wrong!

 

[legion]

i thought yeast dies at the temperature above 37 degrees

it does die at higher temp though i have no idea what temp it is. i think its higher then 37 degrees cuz we heat bread to kill yeast in it! n cooling will also denature it na. cuz it jes operates at optimum temp

 

[SalmanPakRocks]

Actually the Best Temperature for Fermentation is 20 degrees.
The condition require at the above given temperature, A air tight flash as yeast resipire in absense of oxygen.

 

[hassankhan]

Can anyone help me with physics nov 2010 paper 4 question 4.
urgent help

 

[snowbrood]

Can anyone help me with physics nov 2010 paper 4 question 4.
urgent help

paper 41 or paper 42

 

[snowbrood]

it does die at higher temp though i have no idea what temp it is. i think its higher then 37 degrees cuz we heat bread to kill yeast in it! n cooling will also denature it na. cuz it jes operates at optimum temp

what does denature means

 

[snowbrood]

it does die at higher temp though i have no idea what temp it is. i think its higher then 37 degrees cuz we heat bread to kill yeast in it! n cooling will also denature it na. cuz it jes operates at optimum temp

cant we seperate the yeast after killing it by increasing the temperature

 

[legion]

what does denature means

em not sure if my previous was correct. like mod said up there, the best temperature for fermentation is 20 degress. i dunt know which one of these is correct cuz i read tht cooling part on a site..
anyhow, denature means that its destroyed. like an enzyme gets denatured. just like tht yeast can also be denatured as its unicellular!

cant we seperate the yeast after killing it by increasing the temperature

yes we can. but we dunt need to! we can reuse the yeast! when the yeast settles down, we collect our product, just like we do with Penicillium fungi and penicillin. and btw, i asked my teacher today and he said that fermentation of yeast and its products isnt in our syllabus! cheese making, bread making and alcohol making include yeast stuff. and fermentation is mainly concerned with penicillin and insulin making. =)

 

[Ahmedm96]

how to study claasfication ihave a quiz after 5 days

 

[legion]

classification of????

 

[snowbrood]

em not sure if my previous was correct. like mod said up there, the best temperature for fermentation is 20 degress. i dunt know which one of these is correct cuz i read tht cooling part on a site..
anyhow, denature means that its destroyed. like an enzyme gets denatured. just like tht yeast can also be denatured as its unicellular!

yes we can. but we dunt need to! we can reuse the yeast! when the yeast settles down, we collect our product, just like we do with Penicillium fungi and penicillin. and btw, i asked my teacher today and he said that fermentation of yeast and its products isnt in our syllabus! cheese making, bread making and alcohol making include yeast stuff. and fermentation is mainly concerned with penicillin and insulin making. =)

hey fermentation is in syllabus of chemistry

 

[legion]

hey fermentation is in syllabus of chemistry

hmmm
then sorry. i guess u need sum1 else to help ya cuz i havent yet done fermentation of yeast. was talking in reference to bio

 

[Ahmedm96]

classification of????

the whole chapter