BIO Doubts..here..everyone!!

[Alpha45]

AHHH you got me confused !?!?

FSH (folicle stimulating hormone) produced by the pituitary gland in the head , it stimulates the ovary to release oestrogen .

oestrogen : stimulates a new egg to develop in ovary ( inside follicle) it also stimulates new linning to be build .

-----------------------------------

oestorgen stops FSH from forming by negative feedback so no oestorgen in is produced ( so actually it stops it self)

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after egg is released the follicle is the ovary turn into yellow body , LH is then released , it stimulates the yellow body to make progestrone which stimulates the linning of the uterus to become thick to make ready if the egg is fertilized .

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if egg is not fertilized then progestrone levels drop linning of uterus is lost and mesuration cycle starts again .

 

[Divalicious]

AHHH you got me confused !?!?

FSH (folicle stimulating hormone) produced by the pituitary gland in the head , it stimulates the ovary to release oestrogen .

oestrogen : stimulates a new egg to develop in ovary ( inside follicle) it also stimulates new linning to be build .

In my book it says that FSH itself develops the Graafian Follicle in the ovary till it bursts during ovulation and releases egg in oviduct. Oestrogen just repairs the uterus lining after ovulation and stimulates LH production.

 

[Alpha45]

which book your using , i am using the official one from mary jones and geoff jones but some details i got from teacher .

 

[Divalicious]

which book your using , i am using the official one from mary jones and geoff jones but some details i got from teacher .

It's a study-notes book made by my teacher, using information mainly from the official book too and from another book (can't remember the name), but don't start saying it could be wrong, I've never found any mistakes in it. Probably one of us just seems to mis-understand something..

 

[Alpha45]

I think ur teacher did include details (which you need to know about) but she is talking about the same idea . http://en.wikipedia.org/wiki/Follicle-s ... ng_hormone .

 

[narutogirl]

umm. as far as i know..the pitutrity gland plays a big role in this..so it produces the FSH which goes to the ovary and choose an ovum and makes it devlop into a Gaarfian follicle
this follicle then secrets the hormone oestrogen that stops FSH(so no other ova develops) and that oestrogen will stimulate the thickening of the lineing of the uterus...
Again the pitutary gland will produce the the hormone LH so that that follicle that would burst open, it is reason there is ovulation (release of the ovum into the oviduct)
what is left is a yellow body, the corpus luteum..it doesn't stop there...this will now secrete another hormone progesterone which maintains the thickening of the walls of the uterus..
if no fertilization occurs then the corpus leteum withers away and progesterone level drop and so does the walls because nothing is maintaining it..and so menstruation happens

that is why contraceptive pills are used because they provide the body with high levels of these hormones( oestrogen and progesterone ) which makes inhibts the pitutary gland from producing the FSH or LH

 

[Xenarra]

Hey,

Ok, after reading all this (kinda confusing) i just want to make sure if these are right:

Contraceptive pills contain--- oestrogen and progesterone
oestrogen----- thickens uterine lining, inhibits FSH and helps progeterone maintain lining.
progesterone---- drops uterine lining when its in low levels
FSH---- develops follicle
LH--- makes follicle burst when its in high level to form corpus leutem (yellow body)
LH and FSH ---- made in pituary gland
oestrogen and progesterone ----- made by cells surrounding ovum.

SO when FSH and LH are high progesterone is low and so is oestrogen.

just correct me ...try not to make it confusing...thankx

BR,
Xenarra

 

[Divalicious]

oestrogen and progesterone ----- made by cells surrounding ovum.

Progesterone is also made by the placenta during pregnancy, and by the corpus luteum (remains of follicle after bursting) if the egg was fertilized.
[And damn I wanna get the sandwich in your avatar xD]

 

[Xenarra]

oestrogen and progesterone ----- made by cells surrounding ovum.

Progesterone is also made by the placenta during pregnancy, and by the corpus luteum (remains of follicle after bursting) if the egg was fertilized.
[And damn I wanna get the sandwich in your avatar xD]

Hey,
Oh thanks...better note that down too! (Yea lol....i love cheeseburgers!!)

 

[xIshtar]

oestrogen and progesterone ----- made by cells surrounding ovum.

Progesterone is also made by the placenta during pregnancy, and by the corpus luteum (remains of follicle after bursting) if the egg was fertilized.
[And damn I wanna get the sandwich in your avatar xD]

A corpus luteum only forms after fertilisation?? I think not, a corpus luteum is what is formed when the follicle bursts, not due to fertilisation. With or without fertilisation, there is still a corpus luteum.

 

[Xenarra]

oestrogen and progesterone ----- made by cells surrounding ovum.

Progesterone is also made by the placenta during pregnancy, and by the corpus luteum (remains of follicle after bursting) if the egg was fertilized.
[And damn I wanna get the sandwich in your avatar xD]

A corpus luteum only forms after fertilisation?? I think not, a corpus luteum is what is formed when the follicle bursts, not due to fertilisation. With or without fertilisation, there is still a corpus luteum.

Hey,
ok corpus luteum forms when there is a rise in LH right? LH is there for ovulation....ok i htink i got it wrong...correct me!

BR,
Xenarra

 

[Xenarra]

Hey,

I was going thru my note....what in the world is ZONA PELLUSIDA? :S

BR,
Xenarra

 

[Divalicious]

oestrogen and progesterone ----- made by cells surrounding ovum.

Progesterone is also made by the placenta during pregnancy, and by the corpus luteum (remains of follicle after bursting) if the egg was fertilized.
[And damn I wanna get the sandwich in your avatar xD]

A corpus luteum only forms after fertilisation?? I think not, a corpus luteum is what is formed when the follicle bursts, not due to fertilisation. With or without fertilisation, there is still a corpus luteum.

Yep what I meant was that it forms after bursting, but only keeps secreting progesterone if the egg was fertilized. Otherwise it's broken down.

 

[Divalicious]

Hey,

I was going thru my note....what in the world is ZONA PELLUSIDA? :S

BR,
Xenarra

http://en.wikipedia.org/wiki/Zona_pellucida
Seems like some pretty in-detail stuff about fertilization. You sure we have to learn that? Well it's not in my book xD
And yep, LH causes ovulation which is bursting of Graafian Folicle to release ovum into oviduct, and what remains after follicle bursting is the corpus luteum.

 

[narutogirl]

i have a question, about the food chain
do we we include the sun when we draw it cuz our teacher said that but in the syllabus they specifically said start with a producer they didn't mention anything about the sun :/

 

[xIshtar]

i have a question, about the food chain
do we we include the sun when we draw it cuz our teacher said that but in the syllabus they specifically said start with a producer they didn't mention anything about the sun :/

Start with the producer.

 

[xIshtar]

In case any one was wondering about why viruses are not affected by antibiotics...

Basically, viruses are not normal living cells, so they do not have metabolic reactions going on in them. What antibiotics specifically do is disrupt a bacterias metabolism. Hence, they do not work on viruses as viruses do not act like living organisms, but merely take over cells and cause them to replicate the viruses.

 

[Xenarra]

Hey,

I was going thru my note....what in the world is ZONA PELLUSIDA? :S

BR,
Xenarra

http://en.wikipedia.org/wiki/Zona_pellucida
Seems like some pretty in-detail stuff about fertilization. You sure we have to learn that? Well it's not in my book xD
And yep, LH causes ovulation which is bursting of Graafian Folicle to release ovum into oviduct, and what remains after follicle bursting is the corpus luteum.

Hey,

This is what my notes say (lil bits and peices i heard while the teacher was speaking):
sperms have to corss zona pellusida, chemical reaction occurs when sperm touches ovum and only nucleas enters....i think the zona pelllusida surrounds the follicles and they are slimy...thats what i wrote around the diagram of the ovum. :/

BR,
Xenarra

 

[shan5674]

hey

I'm new here and i was going through some of your doubts and answers, they were really helpful thanks everyone

I also would like to clear one of my doubts, i cant understand how to draw a virus with all its structures like the DNA, the protein coat, the envelope and capsomere, does anyone know how to draw them coz i came across a question where they wanted us to draw the virus and the marking scheme had all of the above mentioned in it, im confused, help plzzz

 

[Xenarra]

hey

I'm new here and i was going through some of your doubts and answers, they were really helpful thanks everyone

I also would like to clear one of my doubts, i cant understand how to draw a virus with all its structures like the DNA, the protein coat, the envelope and capsomere, does anyone know how to draw them coz i came across a question where they wanted us to draw the virus and the marking scheme had all of the above mentioned in it, im confused, help plzzz

Hey,
This is what i kind of drew it like:
http://www.google.com/imgres?imgurl...d=1t:429,r:3,s:49&biw=800&bih=509&safe=active

you have to know all three of these....hopefully this helps

BR,
xenarra