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A level Biology: Post your doubts here!

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Acha tw here's the thing ..

First of all as they've given 0.1 mm which is equal to 100 um
If u count the number of units in between the eye piece graticule.. They are 40 units in total
So that means 40 units = 100 um

Now measure the length as in the units using the micrometer scale given.. That is almost 4 units
Now cross multiply

40 units = 100 um
4 units = x

Answer is 10
Is this the question with nucleus?
 
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Acha tw here's the thing ..

First of all as they've given 0.1 mm which is equal to 100 um
If u count the number of units in between the eye piece graticule.. They are 40 units in total
So that means 40 units = 100 um

Now measure the length as in the units using the micrometer scale given.. That is almost 4 units
Now cross multiply

40 units = 100 um
4 units = x

Answer is 10
 
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Isn't histamr released when an antigen binds to an antibody on the mast cell?! Don't the elastic tissues perform the function of recoiling and stretching and bronchi have them...why isn't the trachea folded then? Where is the c=o in glucose? Isn't sucrose diffused I to the drive tube through a cotransport protein??
Histamine released when pathogen invade mast cells, then immune response stimulated and afterwards, antibody binds with the antigen.
Trachea isn't the site of gaseous exchange, so foldings is not needed.
Revise the straight chain structure of glucose!
No, along with hydrogen ions, sucrose is actively transported to the companion cells via carrier proteins(hydrogen ions are transported by diffusion).... That's why translocation is said to be an active process.
 
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Histamine released when pathogen invade mast cells, then immune response stimulated and afterwards, antibody binds with the antigen.
Trachea isn't the site of gaseous exchange, so foldings is not needed.
Revise the straight chain structure of glucose!
No, along with hydrogen ions, sucrose is actively transported to the companion cells via carrier proteins(hydrogen ions are transported by diffusion).... That's why translocation is said to be an active process.
Ohh. Wait but then when do the antibodies attach to the mast cell? In secondary responses its when the pathogen attaches to the antibodies on the mast cell that the mast cell releases histamine right? Could you elucidate the events that take place in the primary allergic response please
Also how are the bronchi involved in gaseous exchange and the trachea isn't?
 
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