BIO CHP 52
The specific process by which a caterpillar becomes a butterfly is called
Metamorphosis
The two primary mechanisms of cell differentiation are conditional specification and
autonomous specification.
The outcome of cleavage during embryonic development is the production of a
blastula
Once an egg has been fertilized, what event(s) are crucial for preventing additional sperm from inserting chromosomes into the egg?
both the cortical reaction and fast block to polyspermy
The stage of development that involves cell division without cell growth is
cleavage
Children born with fetal alcohol syndrome have
cognitive disorders
When a planarium is cut in half, a head will regenerate from the wounded anterior end and a tail will regenerate from the wounded posterior end. This is an example of
conditional specification.
Cells destined to develop into muscle tissue are transplanted to an area where cells are destined to become epithelial cells. If these cells are under autonomous specification what will happen? The cells will
develop into muscle tissue
Which of the following represents the proper order of events in embryonic development?
fertilization, cleavage, gastrulation, neurulation, organogenesis
Stem cells (unspecialized cells) that develop into bone cells have undergone which type of process?
Cellular differentiation
Which of the following is TRUE of fate mapping?
It determines the ultimate structure/function of a particular cell type during embryonic development.
Which of the following is TRUE of cell cleavage?
It involves consecutive cycles of cell division without cell growth and forms a blastula.
Thalidomide, an anticonvulsive and antihistamine medication, was shown to cause severely deformed limbs in children whose mothers took the medication. What might thalidomide do during development?
Impair morphogenetic fields within the embryo.
Which of the following is TRUE of fertilization?
It both restores the egg to a diploid state and activates cell division.
Which of the following germ layer-structure is mismatched?
mesoderm-digestive tract
42. Neural crest cells at the dorsal surface of the neural tube
migrate to many different regions of the body.
The central nervous system first forms during
neurulation
The first group of cells to migrate through the blastopore will become
notochord
Fertilization of human eggs usually takes place in the
oviduct
In a frog embryo, gastrulation
proceeds by invagination and involution as cells roll over the dorsal lip of the blastopore.
The ectoderm is to the central nervous system as the mesoderm is to the
skeletal muscle
Which event of fertilization occurs first?
the acrosomal reaction
Development of all the structures listed below occur during neurulation EXCEPT:
the archenteron.
Which of the following is likely required to initiate cell differentiation during development?
the presence of mRNAs that express cell-specific proteins
The cortical reaction causes
the zona pellucida or vitelline layer to harden.
Which of the following is NOT a morphogen?
cadherin
The process by which cells acquire specialized forms and functions is called
cell differentiation
Spina bifida occurs due to a defect in the development stage
After gastrulation
Hans Spemann and Hilde Mangold conducted pioneering experiments in which they transplanted the dorsal lip of the blastopore in an early gastrula newt to the ventral side of another early gastrula newt. What was the outcome of this experiment?
All of the choices are correct.
Organogenesis
Arises from germ layer cells
Cleavage occurs after implantation into the lining of the uterus. T OR F
False
Neurulation begins with the thickening of the ectoderm over the neural tube. T OR F
False
Red blood cells are derived from endoderm. T OR F
False
The endoderm is a germ cell layer that tends to cover the embryo. T OR F
False
The fast block to polyspermy occurs through a rapid increase in cytosolic calcium within the egg. T OR F
False
The posterior end of the neural tube will develop into the brain. T OR F
False
The sperm and its DNA enters the egg through simple diffusion through the egg plasma membrane. T OR F
False
In chordates, which mesoderm structure forms during gastrulation and provides structural rigidity along the dorsal anterioposterior axis of the embryo?
Notochord
Which health problem(s) are due to environmental factors?
Spina bifida and fetal alcohol syndrome
Melanocytes ultimately arise from
The ectoderm
Why is it important to have a slow block to polyspermy?
The slow block creates a permanent barrier.
Which is not true of cadherin proteins?
They establish morphogenic fields.
Human eggs undergo holoblastic cleavage and compaction during development. T OR F
True
Human embryos are called morula when compaction occurs. T OR F
True
One outcome of gastrulation is the establishment of primordial germ cells, which represent the cell types that form gametes. T OR F
True
The cortical reaction prevents multiple sperm from contributing their chromosomes to the egg. T OR F
True
The differentiation of cells into distinct body parts is induced by morphogens. T OR F
True
Which of the following sequence of events of fertilization is in the proper order?
acrosomal reaction, binding of sperm to egg membrane, fast block to polyspermy, increase in egg cytosolic calcium, and then the slow block to polyspermy
Through studies using the animal cap assay this morphogen was shown to be important for the determination of the different types of mesoderm tissue in the developing embryo.
activin
Which of the following is TRUE of a morphogen? It is a signaling molecule that
induces the differentiation of cells within the embryo.
Cell cleavage during embryonic development in ducks is
meroblastic