DEVELOPMENTAL BIOLOGY EXAM 1
STUDY GUIDE
What is developmental biology? - Answers -The study of the process by which
organisms grow
Is developmental biology synonymous with the study of embryos? - Answers -No,
although developmental biology has aspects of embryo development, it encompasses
other things too
What are examples of developmental biology? - Answers -- study of embryology
- study of stem cells
- study of regeneration
- study of metamorphosis
What is mesenchyme? - Answers -Loose tissue with variable shape
What is ectoderm? - Answers -the germ layer covering the embryo's surface - single
sheet
What causes developmental change? - Answers -- cell shape
- cell proliferation
- cell death
- cell migration
What does BMP stand for? - Answers -bone morphogenetic protein
What does Noggin do? - Answers -Noggin inhibits several BMP by binding
extracellularly, therefore they cannot bind to receptors
What is a gremlin protein? - Answers -Similar to Noggin and is highly expressed in bat
forelimb, Gremlin blocks BMPs to prevent apoptosis.
What is a loss of function experiment? - Answers -One in which organism is engineered
to lack the function of one or more genes
What is a gain of function experiment? - Answers -One in which an organism is
engineered to gain the function of one or more genes
What are homologous structures? - Answers -Those whose underlying similarity arises
from their being derived from a common ancestral structure
- example: human arm and a bat arm
, What are analogous structures? - Answers -Those whose similarity comes from their
performing a similar function rather than arising from a common ancestor (wing of a
butterfly and bird)
Are bird and bat wings homologous? - Answers -No, they are analogous (homologous
as forelimbs)
What is Evo-Devo? - Answers -"evolution and development" Field of biology comparing
developmental processes between organisms of different taxonomic groups to
understand ancestral relationships between them.
How did the bat get its wings? - Answers -During evolution, bats lost BMP expression in
the interdigital tissue for their developing paws, leading the interdigital tissue to persist,
forming the basis for wings. (Gre blocks BMP then FGF blocks inter digital cell death)
What causes holoprosencephaly? - Answers -Mutation in SHH and in other genes that
effect SHH signaling.
- environmental factors such as maternal diabetes, ethanol exposure.
- unknown what causes the spectrum of severity in patient population 'disease states'
Why is the mouse model not good for holoprosencephaly - Answers -The heterozygote
mice look like the wild-type (they do not show a full spectrum) --when they do express
its extreme
- whereas the human SHH heterozygotes exhibit a full spectrum phenotypes
What animal is used instead of mouse to test holoprosencephaly? - Answers -Chicks
The phenotypic variation in terms of SHH signaling and face shape is - Answers -Non-
linear
- small windows of change can cause phenotypic variation
- small magnitude of change is what is believed to show a spectrum
What are nematodes? - Answers -Classified as an insect, tubular digestive system,
ubiquitous (25k to 1mil species)
What is a classic nematode used in developmental biology? - Answers -C. elegans
Why do scientists use C. Elegans? - Answers -- easy to grow
- propagate in petri dishes
- can be frozen
- transparent (can see individual cells)
STUDY GUIDE
What is developmental biology? - Answers -The study of the process by which
organisms grow
Is developmental biology synonymous with the study of embryos? - Answers -No,
although developmental biology has aspects of embryo development, it encompasses
other things too
What are examples of developmental biology? - Answers -- study of embryology
- study of stem cells
- study of regeneration
- study of metamorphosis
What is mesenchyme? - Answers -Loose tissue with variable shape
What is ectoderm? - Answers -the germ layer covering the embryo's surface - single
sheet
What causes developmental change? - Answers -- cell shape
- cell proliferation
- cell death
- cell migration
What does BMP stand for? - Answers -bone morphogenetic protein
What does Noggin do? - Answers -Noggin inhibits several BMP by binding
extracellularly, therefore they cannot bind to receptors
What is a gremlin protein? - Answers -Similar to Noggin and is highly expressed in bat
forelimb, Gremlin blocks BMPs to prevent apoptosis.
What is a loss of function experiment? - Answers -One in which organism is engineered
to lack the function of one or more genes
What is a gain of function experiment? - Answers -One in which an organism is
engineered to gain the function of one or more genes
What are homologous structures? - Answers -Those whose underlying similarity arises
from their being derived from a common ancestral structure
- example: human arm and a bat arm
, What are analogous structures? - Answers -Those whose similarity comes from their
performing a similar function rather than arising from a common ancestor (wing of a
butterfly and bird)
Are bird and bat wings homologous? - Answers -No, they are analogous (homologous
as forelimbs)
What is Evo-Devo? - Answers -"evolution and development" Field of biology comparing
developmental processes between organisms of different taxonomic groups to
understand ancestral relationships between them.
How did the bat get its wings? - Answers -During evolution, bats lost BMP expression in
the interdigital tissue for their developing paws, leading the interdigital tissue to persist,
forming the basis for wings. (Gre blocks BMP then FGF blocks inter digital cell death)
What causes holoprosencephaly? - Answers -Mutation in SHH and in other genes that
effect SHH signaling.
- environmental factors such as maternal diabetes, ethanol exposure.
- unknown what causes the spectrum of severity in patient population 'disease states'
Why is the mouse model not good for holoprosencephaly - Answers -The heterozygote
mice look like the wild-type (they do not show a full spectrum) --when they do express
its extreme
- whereas the human SHH heterozygotes exhibit a full spectrum phenotypes
What animal is used instead of mouse to test holoprosencephaly? - Answers -Chicks
The phenotypic variation in terms of SHH signaling and face shape is - Answers -Non-
linear
- small windows of change can cause phenotypic variation
- small magnitude of change is what is believed to show a spectrum
What are nematodes? - Answers -Classified as an insect, tubular digestive system,
ubiquitous (25k to 1mil species)
What is a classic nematode used in developmental biology? - Answers -C. elegans
Why do scientists use C. Elegans? - Answers -- easy to grow
- propagate in petri dishes
- can be frozen
- transparent (can see individual cells)
