Biology; Chemistry; Physics: Post your doubts here!

[Awesome12]

Keeping the temperature constant.
The amount of water in test tubes be the same
Don't know about the third one but I once read this question in pure where they said that a control should be set up but I don't get why? :/

To make an experiment valid, we also set up a control

 

[Mahnoorfatima]

1) Prepare a control experiment with boiled saliva.
2) Keep the amount of water same in both experiments.
3) The temperature of both experiments should be same.

Why a control? Why don't we use control in other experiments as well??

 

[Fate0]

actually i was going through an investigation in which they have provided
acidic, slightly acidic, neutral, slightly alkaline and alkaline pH to test which works best, they did not mention if the amylase is salivary or pancreatic, so i am confused which results would be positive

In that situation, it's the salivary amylase because we dont use pancreatic for experiments. So neutral is the answer.

Keeping the temperature constant.
The amount of water in test tubes be the same
Don't know about the third one but I once read this question in pure where they said that a control should be set up but I don't get why? :/

A control helps us compare our observations and make a conclusion based on that comparsion.

 

[rida.12.!!]

as salam o alaikum
just a silly question for bio
describe a food test you could do to show that bean seeds contain protein??

 

[Fate0]

as salam o alaikum
just a silly question for bio
describe a food test you could do to show that bean seeds contain protein??

Crush a sample of bean seeds in a mortar.
Add a few cm^3 of biuret solution(NaOH + CuSO4) to the sample.
The blue solution turns violet/purple if protein is present.

 

[Mahnoorfatima]

To make an experiment valid, we also set up a control

Btw we can use a control for any experiment right? Like in expts the one you just asked?

 

[kirann]

In that situation, it's the salivary amylase because we dont use pancreatic for experiments. So neutral is the answer.



A control helps us compare our observations and make a conclusion based on that comparsion.

ok thanks

 

[rida.12.!!]

Crush a sample of bean seeds in a mortar.
Add a few cm^3 of biuret solution(NaOH + CuSO4) to the sample.
The blue solution turns violet/purple if protein is present.

thx!!

 

[Awesome12]

Why is a plant grown in dark taller than a plant grown in light?

 

[Mahnoorfatima]

Why is a plant grown in dark taller than a plant grown in light?

Some plants are adapted to grow in shade.

 

[Awesome12]

Some plants are adapted to grow in shade.

And...

 

[Fate0]

Why is a plant grown in dark taller than a plant grown in light?

When the plant does not receive light, it puts in it's best effort to grow upwards to acquire light.
If it's given light from the start, it wont struggle.

Sorta like if you dont get grades the first time, you put maximum efforts for next.
If you get them the first time, you dont put up that much for the next ones

 

[Mahnoorfatima]

When the plant does not receive light, it puts in it's best effort to grow upwards to acquire light.
If it's given light from the start, it wont struggle.

Sorta like if you dont get grades the first time, you put maximum efforts for next.
If you get them the first time, you dont put up that much for the next ones

^ And.... LOL! Love your explanation. But moon say achi batain nikalo.

 

[Fate0]

^ And.... LOL! Love your explanation. But moon say achi batain nikalo.

There's a reason I used that explanation.
Victim

 

[dakheel]

Assalam-o-Allaikum and Hi everyone ,
hope u all are doin great !

Well as the topic says help for chemistry biology and Physics is available here that means that u can ask any mind blowing question or ask any question regarding a particular topic or ask abt any questions from Past paper or any of your text books.

I made this topic so that people dont make many posts asking abt bio,physics or chemistry individually but they can post their reply here where it can be answered with ease and the members wont have to go searching for topics to help! !

So what are u waiting for now write ur questions here !
THANKS and Bye or Allah Hafiz !

 

[Mahnoorfatima]

There's a reason I used that explanation.
Victim

Oh damn! It's alright! Chill! Life's a roller coaster you know?

 

[Fate0]

Oh damn! It's alright! Chill! Life's a roller coaster you know?

Just praying for the best .

 

[kirann]

how to check if oxygen is given off in respiration?

 

[Laibaaa]

Oh damn! It's alright! Chill! Life's a roller coaster you know?

that only goes up.

 

[Fate0]

how to check if oxygen is given off in respiration?

I think you mean used in?
You set up a beaker with some snails, a CO2 absorbant (KOH), wire mesh, a tube leading out of the beaker to a capillary tube with a dye in it.
As oxygen is used up in beaker, low pressure is created and the dye in the capillary tube moves towards the beaker.