Have a Biology Physiology or a Chemistry question? Ask here.

[Jatt101]

So do you have a biology related question but can't find the answers or want a personalized answer than oppose to wikipedia?

Well you come to right place(or thread). So if you ever wanted to know how T helper cells are able to scan the surface of virus infected cells or how you can make dinitrobenzene? Or anything else...Ask away.

I love biology and would love to have about discussion of any physiology related topics except evolution (theres already the thread for that). :)

[Anti-QuickJay]

"What types of molecules have a difficult time passing through the lipid layer of the membrane, and what types of molecules can pass through easily?"

[Soulphalanx]

it is only permeable to small hydrophobic solutes, but has a very low permeability to polar inorganic compounds and ionic molecules. sugars and salts cant

[Jatt101]

it is only permeable to small hydrophobic solutes, but has a very low permeability to polar inorganic compounds and ionic molecules. sugars and salts cant

Right....Any charged or big molecules can't pass. So stuff like K+ Na+ Cl- can't pass because of thier charge. And certianly big molecules like dimers, carbohydrates, polypetides can't pass through either.

But stuff like steroid hormones and other cholesterol dervatives can easily pass through.

And even though people tell you that water readily crosses the membrane, the mechanism is not simple, water is a polar molecule. I won't go into detail but the phospholipid are rearranged (thermodynamically on thier own) and water passes through. Almost like a shutter door.

And thanks Anti-QuickJay for asking...I hope more question will be asked.

[%chrono trigger%]

For atoms that contain more than one electron, the Pauli Exclusion Principle states that:

1. transition metals have incompletely filled d subshells, EXCEPT from scandium thru copper
2. no 2 electrons in an atom can have the same four quantum numbers
3. Diamagnetic substances are repelled by magnets
4. the most stable arrangement of electrons in subshells is the one with the greatest number of paralel

Lol just wondering if ya know it :)

[Jatt101]

For atoms that contain more than one electron, the Pauli Exclusion Principle states that:

1. transition metals have incompletely filled d subshells, EXCEPT from scandium thru copper
2. no 2 electrons in an atom can have the same four quantum numbers
3. Diamagnetic substances are repelled by magnets
4. the most stable arrangement of electrons in subshells is the one with the greatest number of paralel

Lol just wondering if ya know it :)

Ya I do...

[EminentJonFrost]

what household liquid mixtures make the most energetic reaction? (i want to make a water bottle rocket)
science is more fun with flying objects :)

[Jatt101]

what household liquid mixtures make the most energetic reaction? (i want to make a water bottle rocket)
science is more fun with flying objects :)

Lol...I have no idea. Try ammonium containing fertilizer anything sulfuric acid & nitric acid organic compounds and fix them together so you get this:



Trinitrotluene. AKA TNT.

[Archaemic]

Just don't mix ammonia and bleach ;)

TOXIC FUMES

[Anti-QuickJay]

How do I make a Meth lab?
jkjk

Explain to me why when I put a Mentos inside a Diet Coke it gets all fuzzy and explodes(If I have the cap closed)
Google "Mentos in Diet Soda/Coke" for videos

[Jatt101]

How do I make a Meth lab?
jkjk

Explain to me why when I put a Mentos inside a Diet Coke it gets all fuzzy and explodes(If I have the cap closed)
Google "Mentos in Diet Soda/Coke" for videos

Idk...chemical reaction? :) I'm more of bio, physio & organic chemistry guy.
But I saw the mythbuster episode about this.

Question: What are the ingredients in Diet Coke that cause a reaction with Mentos candies?

Diet Coke and Mentos: CO2, aspartame, potassium benzoate, and caffeine in the Diet Coke, gum Arabic and gelatin in the Mentos, as well as the tiny pits on a Mentos candy (nucleation sites) are responsible for the explosive reaction of Diet Coke and Mentos

[Sir_Axxewraith]

WTF Is shnells law ( Probably spelt wrong )

My teacher always referres to it, but never tells us what it is ..

[Jatt101]

WTF Is shnells law ( Probably spelt wrong )

My teacher always referres to it, but never tells us what it is ..

Snells law? Physics? I hate physics.

Eitherway its to calculate refraction of light when it passes through one medium to another.

Wikipedia explains this better...sorry I dont like physics.



Where theta 1 is angle where light hits the normal and theta2 is the angle where it comes out form...n1 is the refraction constant for the first medium and n2 is refraction index constant for second medium.

If I can recall right air is refraction index is 0 while water is 1. Not sure tho.

[Sir_Axxewraith]

hah me too but I have this program where they chuck you into GCSEs early and i HAVE to do all 3 sciences ( Biologoy, Chemistry and Physics )

Thanks for the reply though

[Archaemic]

Eh, ask me if you have physics questions.

[Anti-QuickJay]

I have Physics question...

1. Three unequal forces act upon a body at a point so that the body is in equilibrium. if the magnitudes of two of the forces are doubled, how much must the third force be changed to preserve equilibrium. justify your conclusion by diagrams.

2. which of the following statements are true? A body in equilibrium :
(a) must be at rest
(b) must move with uniform acceleration
(c) must have uniform linear and rotary velocity,
(d) cannot be acted upon by several forces
(e) must have the sum of the upward forces acting upon it just equal to its weight.

3. a crane boom of negligible weight is 20 ft. long. it makes an angle of 30-degrees with a vertical mast. the tie rope, fastened from the upper end of the boom to the wall, makes an angle of 90-degrees with the boom. the maximum tensile force that the rope can safely stand is 5.0 tons. what is the maximum load the crane can support and the thrust in the boom for this load? solve by both an analytical method and a torque method.

Answers please.

[Jatt101]

1. Don't I need to know the angle for the forces?

2. C Rotational equilibrium & 0 net force are needed.

3. I don't want to do math.

Eh, ask me if you have physics questions.

I'll hold you up for that. Your turn.

[filberto]

Physics question:
If you were travelling at half the speed of light, and turned on a light, sureley the light you are emitting would be travelling at the speed of light + half the speed of light, therefore it is travelling faster than the speed of light, meaning you could travel faster than the speed of light.

I have a feeling this is wrong but why?

[Sir_Axxewraith]

homework ?

lmao

[filberto]

Nah, I was just wondering...

[Jatt101]

Physics question:
If you were travelling at half the speed of light, and turned on a light, sureley the light you are emitting would be travelling at the speed of light + half the speed of light, therefore it is travelling faster than the speed of light, meaning you could travel faster than the speed of light.

I have a feeling this is wrong but why?

Your wrong because you don't know what the doppler effect is. Lets say a plane is moving at some speed to north of you and its emiting some type of frequency (sound, radio waves, or even light). You will hear or see the frequency at a different wavelength....I think. I'm pretty weak at physics. But heres a link.

http://en.wikipedia.org/wiki/Doppler_effect

[filberto]

I know what the doppler effect is. Redshift and blueshift and so on. I dont see how this changes anything.

[Jatt101]

I know what the doppler effect is. Redshift and blueshift and so on. I dont see how this changes anything.

I think the light will be at different frequency (and maybe wavelength) but the same speed. In other words it won't change the speed just the frequency & wavelength.

And once again I'm not good at physics...I might just be feeding you lies.

[Archaemic]

Physics question:
If you were travelling at half the speed of light, and turned on a light, sureley the light you are emitting would be travelling at the speed of light + half the speed of light, therefore it is travelling faster than the speed of light, meaning you could travel faster than the speed of light.

I have a feeling this is wrong but why?

This is indeed wrong because spacetime is not Euclidean, but in fact a Minkowski space, which behaves differently. The speed of light is absolute. Addition of velocities is no longer linear at relativistic speeds (speeds close to the speed of light). What you're getting into here is special relativity. No matter which direction you're traveling or what speed your traveling, the speed of light is the same in all directions as it would be if you were perceived to be at rest. All inertial reference frames (that is, reference frames that are not accelerating) are equivalent.

It has nothing to do with the doppler effect

I have Physics question...







Answers please.

Sorry, but I won't do your homework for you. Those questions are just too specific to be anything else :/

[Jatt101]

It has nothing to do with the doppler effect

Good because I had no idea what I was taking about. Thanks for correcting me.

[Archaemic]

If there was such a thing as the ether, then the doppler effect would come into play. However, it's been proven time and time again that there is no ether. Light is a very special wave. Well, I guess all massless particles behave similarly (eg photons, gluons, possibly gravitons)

[Anti-QuickJay]

Sorry, but I won't do your homework for you. Those questions are just too specific to be anything else :/

lmao!
These arent my homework questions.
I googled HArdest Physics questions and found these on Yahoo answers. Just thought I'd test your brain.

[Realn0whereman]

I Lub math, and even less physics... most math, ill be able to help in, as for physics, ill see what i can remember from last years' AP phys

[Jatt101]

Yay..we got another physics person to help.

Now we just need some questions...bio questions preferred.

[Vee]

In a star, H+H = He.

Now Hydrogen cancells out Gravitys force on the star, pulling it inwards.

Why?


Sorry i phrased that badly..but do you understand?