Antibodies in breast milk

[bips]

1) Mother's milk contain antibodies. The milk enters baby's alimentary canal. How do these antibodies enter baby's bloodstream from alimentary canal so as to protect it from diseases?
2) Why does a man need two testis instead of one?

[sachin]

1) It is matter of my interest too..... Dont know..

2) Two testes is not a need but its an ancestral trait that have carried by us..... Slowly those will degrade in one..... as further evolution will take place....

[MrMistery]

1. because they are absorbed by pinocytosis.
2. why do we have two lungs instead of one big one? why two kidneys instead of one big one? no idea... we evolved that way

[Darby]

An infant's digestive system is more "leaky" than an adults - whole proteins can get through without having to be broken down first (that's the basis of the cow-albumin-as-allergen theory of diabetes 1).

Bilateral symmetry is a natural result of one-direction locomotion, the same thing that "produces" a head end - you need drive structures balanced, and the hox genes that bring this about pretty much produce a right-and-left version of most structures.

[radu]

yes Darby...but i'm having a question too...the antibodies we are talking about, IgG more exactly, are proteins, right?aren't they supposed to be digested by the baby's digestive enzymes?

For the second question...maybe it's a failsafe feature

[Poison]

As much as I know IgA is high in milk.
A baby's digestive system has some differences compared to an adult. (I mean some enzymes' being more or less active etc...) It can be something to do with these differences. Just a guess.

And about the second question, I think the most logical answer is bilateral symmetry.

[Vagabond]

Yes, antibodies are provided to the infant via the mother milk and all types have been observed to be present in the milk (IgG, IgA, IgM, IgD and IgE) and as Poison points out IgAs are present at high concentrations within the mothers milk.

Now IgAs do not need to get into the fetal blood in order to protect the infant. IgAs are normally expressed on mucosal surfaces and will very nicely do a their job in the gut of the infant, until the little one can make its own IgAs.

As for have two I agree with Poison again bilateral symmetry and perhaps a hint of evolution safety. If you have only one and lost it then no offspring for you and your ability to pass on your genetics is prevented.

[Dr.Stein]

What 'bilateral symmetry' thing?

[Vagabond]

http://en.wikipedia.org/wiki/Symmetry_(biology)

[Dr.Stein]

WTH! I DO know about symmetry, bilateral symmetry, radial symmetry, asymetry, etc. etc. My question was what bilateral symmetry thing were you talking about in previous post?

I guess it is about IgA structure, something like this: >-< Well, that structure is needed because the immunoglobulin needs to delivered from lamina propria to lumen via internalization (engulfment). One end will anchor the mucus while the other end will bind the antigen.

[MrMistery]

the discussion was about bilateral symmetry in reagard to the fact that we have to testicles, two lungs, two kidneys etc

[Dr.Stein]

Damn, where was my concentration go???