ZOO 3603C - Exam 1 Sample
Questions Answered & Graded
How has developmental biology impacted modern medicine? - Correct Answer IVF (in
vitro fertilization)
teratology - study of congenital abnormalities
Birth defects, prenatal diagnosis
cloning
What is regulation? - Correct Answer the ability to respecify cells so that the removal of
cells destined to become a particular structure can be compensated for by other cells
producing that structure
Who discovered Regulation? - Correct Answer Roux
What is determination? - Correct Answer the second and irreversible stage of a cell or
tissue commitment in which the cell or tissue is capable of differentiating autonomously,
even when placed in a non neutral environment
What "proved" determination - Correct Answer Weisman and Conklin
Experimented with snail eggs and found that the germ layers were determined because
macho-1 was only found in early mesodermal cells and could not be reversed
Shown to only be true in certain organisms
What enables us to be able to do IVF and prenatal diagnosis? - Correct Answer Human
embryo is regulative. Therefore, you can take one of the eight human blastula cells and
it is not detrimental to development.
What did Hartsoeker believe about development? - Correct Answer He was a
preformationist. He looked at his sperm through a lens and believed that a tiny man was
sitting in the acrosome. The yolk allows the fetus to grow
What did Driesh believe? - Correct Answer Entelechy
A vital force drives development
What did Child believe? - Correct Answer Metabolic gradients determined the different
embryonic laters
No molecular bio to back it up though
Who discovered the organizer and how? - Correct Answer Spemann discovered the
organizer by grafting it to the other side of a xenopus embryo
-Wolpart also proposed the organizer!
What are examples of the organizer? - Correct Answer Dorsal lip of the blastopore
(xenopus)
Zone of Polarizing Activity (organizer in chick limb bud)
, Notochord (organizes DV axis in spinal chord)
How do the organizers work? - Correct Answer Cells interpret what to do based on their
position in a field. Position determined by concentration of morphogen.
What is "in situ" hybridization? - Correct Answer A technique used to localize mRNA
Show's how morphogens are produced in a gradient and diffuse
What are common morphogens? - Correct Answer Shh
FGFs
Wnts
BMP (activin)
Nodal
RA - retinoic acid
What stops the morphogen from diffusing across an entire embryo? - Correct Answer
Antagonists switch the signal off
What commits the germ cells to their fate early? - Correct Answer cytoplasmic
determinants (germ plasm/mRNA)
How do germ cells arise in C. eleganS, drosophila, xenopus, and
salamanders/mammals? - Correct Answer C. elegans - polar granules
Drosophila - pole plasm
Xenopus - germ plasm
Salamander/Mammal - induction
What allows induction of germ cells in mammals? - Correct Answer BMPs (bone
morphogenic protein), sox2, nanog, oct4
What happens after germ cells are induced in mammals? - Correct Answer Produced in
yolk sac, move to abdominal cavity, then genital ridges
What determines male germ cells? - Correct Answer SRY gene on Y chromosome
kicks in
What determines female germ cells? - Correct Answer no SRY gene - default female
What is the difference in meiosis between male and female germ cells? - Correct
Answer Females start meiosis immediately, and then stop until puberty.
Male do not start meiosis until puberty
What happens during ovulation in a female? - Correct Answer First polar body forms
Moves on from first meiosis to secondary meiosis division
Questions Answered & Graded
How has developmental biology impacted modern medicine? - Correct Answer IVF (in
vitro fertilization)
teratology - study of congenital abnormalities
Birth defects, prenatal diagnosis
cloning
What is regulation? - Correct Answer the ability to respecify cells so that the removal of
cells destined to become a particular structure can be compensated for by other cells
producing that structure
Who discovered Regulation? - Correct Answer Roux
What is determination? - Correct Answer the second and irreversible stage of a cell or
tissue commitment in which the cell or tissue is capable of differentiating autonomously,
even when placed in a non neutral environment
What "proved" determination - Correct Answer Weisman and Conklin
Experimented with snail eggs and found that the germ layers were determined because
macho-1 was only found in early mesodermal cells and could not be reversed
Shown to only be true in certain organisms
What enables us to be able to do IVF and prenatal diagnosis? - Correct Answer Human
embryo is regulative. Therefore, you can take one of the eight human blastula cells and
it is not detrimental to development.
What did Hartsoeker believe about development? - Correct Answer He was a
preformationist. He looked at his sperm through a lens and believed that a tiny man was
sitting in the acrosome. The yolk allows the fetus to grow
What did Driesh believe? - Correct Answer Entelechy
A vital force drives development
What did Child believe? - Correct Answer Metabolic gradients determined the different
embryonic laters
No molecular bio to back it up though
Who discovered the organizer and how? - Correct Answer Spemann discovered the
organizer by grafting it to the other side of a xenopus embryo
-Wolpart also proposed the organizer!
What are examples of the organizer? - Correct Answer Dorsal lip of the blastopore
(xenopus)
Zone of Polarizing Activity (organizer in chick limb bud)
, Notochord (organizes DV axis in spinal chord)
How do the organizers work? - Correct Answer Cells interpret what to do based on their
position in a field. Position determined by concentration of morphogen.
What is "in situ" hybridization? - Correct Answer A technique used to localize mRNA
Show's how morphogens are produced in a gradient and diffuse
What are common morphogens? - Correct Answer Shh
FGFs
Wnts
BMP (activin)
Nodal
RA - retinoic acid
What stops the morphogen from diffusing across an entire embryo? - Correct Answer
Antagonists switch the signal off
What commits the germ cells to their fate early? - Correct Answer cytoplasmic
determinants (germ plasm/mRNA)
How do germ cells arise in C. eleganS, drosophila, xenopus, and
salamanders/mammals? - Correct Answer C. elegans - polar granules
Drosophila - pole plasm
Xenopus - germ plasm
Salamander/Mammal - induction
What allows induction of germ cells in mammals? - Correct Answer BMPs (bone
morphogenic protein), sox2, nanog, oct4
What happens after germ cells are induced in mammals? - Correct Answer Produced in
yolk sac, move to abdominal cavity, then genital ridges
What determines male germ cells? - Correct Answer SRY gene on Y chromosome
kicks in
What determines female germ cells? - Correct Answer no SRY gene - default female
What is the difference in meiosis between male and female germ cells? - Correct
Answer Females start meiosis immediately, and then stop until puberty.
Male do not start meiosis until puberty
What happens during ovulation in a female? - Correct Answer First polar body forms
Moves on from first meiosis to secondary meiosis division
