Human BiOlogy.

[Deadly_king]

Thank You.   Really helped. +rep

Anyways,

C0₂ reacts with lime water when blown through it to form a chalky suspension. Suggest how you could use this information to show that you produce more CO₂ when you exercise than when you are at rest.

You're welcome

Hmm........the concentration of the chalk suspension will reveal its amount.

Firstly, when you are at rest, expired air is blown into a boiling tube containing lime water for about 10s.

Now take another similar test-tube containing same amount of lime water. After having exercised, expired air is blown into the test-tube for the same lapse of time.

NOTE : Keeping all the above mentioned variables constant is very important so that the results of your experiment are affected only by concentration of carbon dioxide from expired air.

You will note that the suspension is thicker in the second test-tube. This will indicate that more carbon dioxide is present in expired air when you exercise than when at rest.

[iluvme]

Oh okay thanks.
I was thinking about the number of breaths and stuff. 

[Deadly_king]

Oh okay thanks.
I was thinking about the number of breaths and stuff. 

Anytime

Yeah ......... you can take the number of breaths instead of 10 seconds. It would turn out to be the same

The key part is to keep it constant for both experiment. So if you took 10 breaths for the first one, you should take 10 breaths for the second one as well

[iluvme]

Righto, thanks.                                                                                                                                 

Distinguish between the terms meiosis and mitosis.
For this Q, should we write about the number of daughter cells obtained, the chromosomes and stuff?

[The Golden Girl =D]

http://www.differencebetween.net/science/difference-between-mitosis-and-meiosis/

http://www.answerbag.com/q_view/278075

I hope i helped

[iluvme]

Thanks Muallima 

This Question too, Two insects mosquito and housefly spread diseases through their saliva. Explain how this is achieved. This is a two mark Q.

[The Golden Girl =D]

Actually i don't know but I'll give u smthn that will help :S

http://www.mosquitoworld.net/mosquitodiseases.php

http://www.pitara.com/discover/5wh/online.asp?story=45

:S :S

[Master_Key]

The parasites enter their salivary glands. Here they multiply, the saliva contains anti-coagulant which stops the blood from clotting. When the insects bite they inject their saliva into the human's body and human gets infected.

[Deadly_king]

The parasites enter their salivary glands. Here they multiply, the saliva contains anti-coagulant which stops the blood from clotting. When the insects bite they inject their saliva into the human's body and human gets infected.

That's correct

I confirm master_key's answer

[iluvme]

Thanks muallima, master key and deadly king 
How about the house fly?

Explain why one contact with an infected mosquito can lead to malaria but repeated larval contacts are needed to produce symptoms of schistosomiasis.

[Deadly_king]

Thanks muallima, master key and deadly king 
How about the house fly?

Explain why one contact with an infected mosquito can lead to malaria but repeated larval contacts are needed to produce symptoms of schistosomiasis.

Am not 100% confident about this..............but my answer is quite reasonable

Both the house fly and the mosquito operate by sucking blood from a person. In doing so, their saliva get into direct contact with the person's blood ,hence infecting him.

Larva however have not yet developed structures with which they'll be sucking blood. Hence it will take some time for them to grow into adults. Only then will they be harmful to us.

Hope it helps

[iluvme]

My book dsn't explain clearly too. 
By the way, those were 2 dffrnt questions.

[Deadly_king]

My book dsn't explain clearly too. 
By the way, those were 2 dffrnt questions.

I'll try to get more info and will let you know

Yeah..........I know they are two different questions

But house flies and mosquitoes operate the same way

[iluvme]

OKiez thank You.

[elemis]

Since when do common house flys suck blood from a person ? They dont have the hypodermic needle like thing that mosquitoes have....