Biology - March 2007

Humans have evolved to desire sex through numerous hormonal chemicals. But what mechanism exists to make humans want to have children? In general, humans desire sex but now that numerous birth control methods exist, sex is no longer necessarily tied to having children. So what biological reason makes humans want to have children, because many could have sex and no children if they so desired. And, it seems to me that such a scenario is in effect. Children per adult is decreasing in nations where the populations can easily afford a lifetime supply of birth control. But why doesn't the rate go down to zero for that group of people? Of course, I'm not advocating this, I'm just wondering why we see these results.

2007-03-17 06:19:04 · 14 answers · asked by presidentrichardnixon 3

2007-03-17 06:09:50 · 2 answers · asked by macy012501 2

what are the differences between mitosis and meiosis?

2007-03-17 06:07:10 · 3 answers · asked by Anonymous

2007-03-17 05:57:01 · 1 answers · asked by musicloverboy88 2

2007-03-17 05:49:33 · 1 answers · asked by Anonymous

Thorium-234 has a half life of 24days. If 72 days passed before a corspe was found, what fraction of Thorium-234 would you expect to still be radioactive in the vitcims body?

2007-03-17 05:47:11 · 6 answers · asked by vballchik104 1

Okay, if anyone could point me out to a website with these chemical equations or tell me what they are, I would really appreciate it...I have them answered (and posted this in the chemistry section, they directed me here), but I seriously doubt they're right and this is worth some major points.

1 - A synthesis reaction that is happening in your body.
2 - A decompostion reaction that is happening in your body.
3 - A replacement reaction happening in your body.
4 - A combustion react happening in your body.
5 - List some catalysts being used in reactions in the body.
6 - (answered)
7 - Why is it necessary for humans that calcium carbonate is not water soluble?

2007-03-17 05:28:01 · 4 answers · asked by Anonymous

She is in need of a animal cell as well as plant cell diagram and definition about each part of the animal and plant cells, she needs a function as well, but it has to be in simple terms that she can understand. Please can someone help us out?? Thank you

2007-03-17 05:23:31 · 2 answers · asked by Anonymous

2007-03-17 05:16:13 · 1 answers · asked by dear 1

I know the sperm die, but does the body have an immnune system response? Like do macrophages(white blood cells) eat the foreign cells as if it were a diseases cell or a pathogen? Where do they go?

2007-03-17 04:34:07 · 5 answers · asked by naztakuan 2

A starfish is an invertabrate...isnt it?

please answer quickly!!

cheers

2007-03-17 04:33:24 · 12 answers · asked by gregandkerry 1

just something I've been pondering..

and if someone is a vegetarian, does their poop differ from meat-lovers?

2007-03-17 04:21:17 · 6 answers · asked by brubabe 5

a. Explain, referring to sharing, losing or acquiring electrons, why 2 O atoms joined together are stable, whereas individually they are not. (Include mention of how many valence electrons are in the neutral atom.)
b. What kind of bond occurs in a molecule of O2?
c. Explain why electrolyte solutions will conduct electricity but covalent solutions will not.
d. What are the major cation and the major anion in extracellular fluid?

2007-03-17 01:25:55 · 4 answers · asked by Anonymous

2007-03-17 01:25:44 · 5 answers · asked by Anonymous

say one twin wanted to walk forward, but the other didn't, which brain command do the legs take?

2007-03-17 01:19:34 · 4 answers · asked by Anonymous

My question is related to color blindness?

actually I am hoping to frind different researches about the subject but manily I wanted to ask if any got a link to a website that give 'color vision' test .........

for my prsentation tommorow

please Help......and thanks either ways....m _ m

2007-03-17 00:34:01 · 7 answers · asked by Wonkyu 4

1=5
2=25
3=125
4=625
WAT DOES 5=?

2007-03-17 00:12:00 · 2 answers · asked by Anonymous

i do not know the different between carrier protein and pore protein in plasma membrane.

2007-03-17 00:04:02 · 2 answers · asked by meLLious_liya 1

a diagram of the flow of blood
pictures with explanation

2007-03-16 23:11:53 · 5 answers · asked by sweet sugar 3

as we know the translation of mRna always started with codon AUG so result in Methionine amino acid..but if u can see..the insulin or the ribonucleus didnt start with MET..why?

2007-03-16 22:28:01 · 2 answers · asked by mohdfairuz 2

platelet origion from bone marrow and it is fragment of larger cell in bone marrow..even leucocyte can pass the tiny hole in capillary but why the platelet can't?of coz the leucocyte can pass through becoz it can squeeze itself but why this tiny thing can't?

2007-03-16 22:03:35 · 2 answers · asked by mohdfairuz 2

2007-03-16 21:14:29 · 11 answers · asked by Anonymous

please give the proper meaning of allele. I would be thankful to answerers

2007-03-16 20:58:55 · 5 answers · asked by PearL 4

I have a child who is 15 years old.She doesn't have a sound sleep.For example,if she sleeps at 12 she wakes up at 4 and then till two hours she doen't feel like sleeping.Like this she keeps waking up after some time.Can anybody tell me the reason for this????

2007-03-16 20:37:03 · 6 answers · asked by Twarita 2

2007-03-16 20:09:44 · 5 answers · asked by Dantte 1

What do/can you observe that is evidence of the major event in anaphase?

2007-03-16 19:59:11 · 3 answers · asked by Anonymous

Please help!

2007-03-16 19:35:12 · 1 answers · asked by plsw11 1

2007-03-16 19:14:06 · 5 answers · asked by shin0 1

2007-03-16 18:53:45 · 9 answers · asked by coprightman 1

Please include as much specific information as possible, like what IgA recognizes, Igd recognizes, etc.

2007-03-16 17:49:28 · 3 answers · asked by beefy083 1