Take this test:

[osimsDDS]

What does the Trophoblast form after implantation to the uterus?
a) HCG
b) Yolk Sac
c) estrogen
d) progesterone
e) growth hormone

During ovulation what happens?
a) high levels of progesterone signal positive feedback to inhibit LH
b) high levels of progesterone signal negative feedback to inhibit LH
c) high levels of estrogen signal negative feedback to induce LH
d) high levels of estrogen signal positive feedback to induce LH
e) Low levels of FSH signal positive feedback to induce LH

If you were to take out a cell from the non-gray (gray crescent) area of a developing frog embryo during early cleavage what would happen?
a) it would grow
b)it would undergo cleavage but only for a short while
c) it would not grow at all
d) it would grow only under certain nutrients
e) none of the above

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[doc3232]

B
D
A

Random guessing because I know nothing of Bio.

 

[Hugh Mannity]

A
D
A

I'm only certain on 1 and 2. 3 is a guess.

 

[sdooner30]

i know the trophoblast produces HCG. But it later forms the chorion....

 

[osimsDDS]

yea, answers are as follows:

1) A, the trophoblast produces HCG which keeps the embryo from breaking down until the placenta forms from the chorion which produces progesterone...
2) D, pretty straight forward, positive feedback occurs during ovulation when increased estrogen increases LH.
3) C, the grey-are or crescent is the most important part of the early embryonic formation in a frog. If you take a cell from the vegetal pole (no grey area) it will not grow by itself. If you take a cell from the animal pole (grey area) it will be able to grow into a new embryo by itself...

 

[gkhan]

nvm yo gave the answers

 

[osimsDDS]

my bad, ill make another test later and wait until more ppl answer next time sorry...

 

[theedaddy77]

what is the trophblast and where does it come from?