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