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A level Biology: Post your doubts here!

huh

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Hey guys. So I was going through some past papers and one questions came up about Cisternae. I wanted to find more about this in my textbook but I can't seem to find anything about it in my book. I have the A Level Biology Coursebook by Mary Jones (it's got a butterfly on the cover). If anyone has any material or the page number, it would be of great help.
 
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Hey guys. So I was going through some past papers and one questions came up about Cisternae. I wanted to find more about this in my textbook but I can't seem to find anything about it in my book. I have the A Level Biology Coursebook by Mary Jones (it's got a butterfly on the cover). If anyone has any material or the page number, it would be of great help.
Cisternae is the system of flattened memebrane-bounded sacs in the endoplasmic reticulum. Even the folded sacks for the golgi body are called cisternae.
 
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limit of resolution is about one half of the radiation that is being used to view the specimen. In other words, if object ( that is being viewed) is any smaller than half the wavelength that is being used to view it, it can no be seen separately.
Okay but why option C is wrong?
 
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Also,what was the answer for 'germinating seed from botanic garden every few years? i wrote in order to keep the seed germinating and or protect it from drying and thus protecting the endangered specie etc.
I answered DNA will become worse and worse every year. Also when they are grown, they can produce more and more seeds..... (Hope I'm correct)
 
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Hi everyone, assalamoalaikum!! :)

To get things organized in a better way, I am making this thread. As othewise, some queries remain unanswered!

So post your A LEVEL BIOLOGY doubts in this thread. InshaAllah those who can , will help me and you all. :D ;)

Will try to update this soon, by adding links to some Biology Notes & Links around the forum.

Thanks!
Jazak Allah Khair!

BIOLOGY LINKS & NOTES :


B!0l0gy $l!de$ & N0te$... :) - by workinghard

Biology Practical notes!! - by libra94

http://www.biologymad.com

http://www.biologyinnovation.co.uk

Action Potential - Notes
9700/13/O/N/10 (q 34 38 and 40) asap romorows my exam :(
Hi everyone, assalamoalaikum!! :)

To get things organized in a better way, I am making this thread. As othewise, some queries remain unanswered!

So post your A LEVEL BIOLOGY doubts in this thread. InshaAllah those who can , will help me and you all. :D ;)

Will try to update this soon, by adding links to some Biology Notes & Links around the forum.

Thanks!
Jazak Allah Khair!

BIOLOGY LINKS & NOTES :


B!0l0gy $l!de$ & N0te$... :) - by workinghard

Biology Practical notes!! - by libra94

http://www.biologymad.com

http://www.biologyinnovation.co.uk

Action Potential - Notes
 
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Hi everyone, assalamoalaikum!! :)

To get things organized in a better way, I am making this thread. As othewise, some queries remain unanswered!

So post your A LEVEL BIOLOGY doubts in this thread. InshaAllah those who can , will help me and you all. :D ;)

Will try to update this soon, by adding links to some Biology Notes & Links around the forum.

Thanks!
Jazak Allah Khair!

BIOLOGY LINKS & NOTES :


B!0l0gy $l!de$ & N0te$... :) - by workinghard

Biology Practical notes!! - by libra94

http://www.biologymad.com

http://www.biologyinnovation.co.uk

Action Potential - Notes
Hi everyone, assalamoalaikum!! :)

To get things organized in a better way, I am making this thread. As othewise, some queries remain unanswered!

So post your A LEVEL BIOLOGY doubts in this thread. InshaAllah those who can , will help me and you all. :D ;)

Will try to update this soon, by adding links to some Biology Notes & Links around the forum.

Thanks!
Jazak Allah Khair!

BIOLOGY LINKS & NOTES :


B!0l0gy $l!de$ & N0te$... :) - by workinghard

Biology Practical notes!! - by libra94

http://www.biologymad.com

http://www.biologyinnovation.co.uk

Action Potential - Notes
9700/13/O/N/10 (q 34 38 40) explain me please asap tomorrow is my exam :(
 
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asthma is a lung disease triggered by the inhalation of an allergen such as pollen or dust. the allergen triggers:

-bronchi and bronchioles to become inflamed and narrow
-goblet cells lining these airways to secrete excess mucus.

Which effect will these responses have on the gaseous exchange system of a person with asthma?

1. decrease the diffusion gradient for oxygen in the lungs
2. increase the diffusion distance from the alveoli into the blood
3. increase the risk of developing a lung infection

A. 1,2
B. 1,3
C. 2,3
D. 3 only

Answer please? thanks!
 
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which statements explain why cholera has not been eradicated by vaccination?

1. cholera is caused by the bacterium vibrio cholerae
2. many people can have the disease, but show no symptoms
3. people are mobile due to global trade and tourism
4. the cholera pathogens target cells in the small intestine

A. 1,2,3,4
B. 1,2
C. 2,4
D. 3,4

Answer please? thanks!
 
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which statements explain why cholera has not been eradicated by vaccination?

1. cholera is caused by the bacterium vibrio cholerae
2. many people can have the disease, but show no symptoms
3. people are mobile due to global trade and tourism
4. the cholera pathogens target cells in the small intestine

A. 1,2,3,4
B. 1,2
C. 2,4
D. 3,4

Answer please? thanks!
Is it A?
 
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asthma is a lung disease triggered by the inhalation of an allergen such as pollen or dust. the allergen triggers:

-bronchi and bronchioles to become inflamed and narrow
-goblet cells lining these airways to secrete excess mucus.

Which effect will these responses have on the gaseous exchange system of a person with asthma?

1. decrease the diffusion gradient for oxygen in the lungs
2. increase the diffusion distance from the alveoli into the blood
3. increase the risk of developing a lung infection

A. 1,2
B. 1,2
C. 2,3
D. 3 only

Answer please? thanks!
Are you sure this opt are correct?
 
Messages
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asthma is a lung disease triggered by the inhalation of an allergen such as pollen or dust. the allergen triggers:

-bronchi and bronchioles to become inflamed and narrow
-goblet cells lining these airways to secrete excess mucus.

Which effect will these responses have on the gaseous exchange system of a person with asthma?

1. decrease the diffusion gradient for oxygen in the lungs
2. increase the diffusion distance from the alveoli into the blood
3. increase the risk of developing a lung infection

A. 1,2
B. 1,2
C. 2,3
D. 3 only

Answer please? thanks!
RoOkaYya G wat you say in this ques?
 
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