BIO 351 MODULE 1 (2026/2027) QUESTIONS
AND CORRECT ANSWERS GRADED A+
Within the early embryo, the primary heart field develops in response to high
levels of bone morphogenic proteins (BMPs) and fibroblast growth factor 8
(FGF8) at the rostral end of the embryo. This is an example of which of the
following?
Morphogen gradient
You grow mesenchymal cells in Dish A and epidermal cells in Dish B. If you take
the liquid medium only (containing no cells) from Dish A and place some of it into
the liquid medium covering the epidermal cells in Dish B, you notice that it causes
the epidermal cells to round up and thicken. What developmental concept does this
example best describe?
Induction of epithelial cells by paracrine signaling from mesenchymal cells.
The normal morphogen gradient in a limb bud is shown in the diagram below on
the left. The panel on the right shows the levels of morphogen after a bead soaked
with SHH is transplanted into the rostral side of a limb bud. Which of the
following (A-E) best describes the expected pattern of digits?
Not E
, During eye development, a region of the developing brain grows outwards to be
adjacent to the surface ectoderm. These two tissues then differentiate into the retina
and lens, respectively. Placing a piece of aluminum foil between these two tissues
blocks both of these differentiation processes. However, placing a piece of
permeable membrane allows both processes to proceed.
Based on these observations, what type of signaling is taking place?
Paracrine- inducer released from a distance
The diagram below shows an example of juxtacrine signaling. Cell-cell contact is
mediated through the __________ ligand on the inducing cell and
___________receptor on the responding cell in this pathway.
Delta, Notcht
In the signaling diagram on the below, the ligand binds to a ________ . Fill in the
blank.
Receptor tyrosine kinase
Wnts play an important role in promoting EMT in developing neural crest
progenitors. What is the receptor for secreted Wnts?
Frizzled
Application of FGF8 coated beads induce limb mesenchymal cell proliferation. In
contrast, FGF8 coated beads implanted on the epidermis of the back do not
promote proliferation. This experiment provides an excellent example of which of
the following?
AND CORRECT ANSWERS GRADED A+
Within the early embryo, the primary heart field develops in response to high
levels of bone morphogenic proteins (BMPs) and fibroblast growth factor 8
(FGF8) at the rostral end of the embryo. This is an example of which of the
following?
Morphogen gradient
You grow mesenchymal cells in Dish A and epidermal cells in Dish B. If you take
the liquid medium only (containing no cells) from Dish A and place some of it into
the liquid medium covering the epidermal cells in Dish B, you notice that it causes
the epidermal cells to round up and thicken. What developmental concept does this
example best describe?
Induction of epithelial cells by paracrine signaling from mesenchymal cells.
The normal morphogen gradient in a limb bud is shown in the diagram below on
the left. The panel on the right shows the levels of morphogen after a bead soaked
with SHH is transplanted into the rostral side of a limb bud. Which of the
following (A-E) best describes the expected pattern of digits?
Not E
, During eye development, a region of the developing brain grows outwards to be
adjacent to the surface ectoderm. These two tissues then differentiate into the retina
and lens, respectively. Placing a piece of aluminum foil between these two tissues
blocks both of these differentiation processes. However, placing a piece of
permeable membrane allows both processes to proceed.
Based on these observations, what type of signaling is taking place?
Paracrine- inducer released from a distance
The diagram below shows an example of juxtacrine signaling. Cell-cell contact is
mediated through the __________ ligand on the inducing cell and
___________receptor on the responding cell in this pathway.
Delta, Notcht
In the signaling diagram on the below, the ligand binds to a ________ . Fill in the
blank.
Receptor tyrosine kinase
Wnts play an important role in promoting EMT in developing neural crest
progenitors. What is the receptor for secreted Wnts?
Frizzled
Application of FGF8 coated beads induce limb mesenchymal cell proliferation. In
contrast, FGF8 coated beads implanted on the epidermis of the back do not
promote proliferation. This experiment provides an excellent example of which of
the following?