Eha Chap 3

Front 1

When does prenatal development begin and end?

Back 1

start of pregnancy until birth of the child

Front 2

What begins at the start of pregnancy until the birth of the child?

Back 2

prenatal development

Front 3

What is the study of prenatal development?

Back 3

embryology

Front 4

What are the 3 distinct periods of prenatal development?

Back 4

preimplantation, embryonic, and fetal periodq

Front 5

When is the preimplantation period?

Back 5

first week

Front 6

What is the embryonic period?

Back 6

second week to eighth week

Front 7

What is the fetal period?

Back 7

third to nine months

Front 8

What is the name for birth defects?

Back 8

congenital malformations

Front 9

When can congenital malformations occur?

Back 9

during preimplantation period and embryonic period

Front 10

Congenital malformations can happen how?

Back 10

genetically or teratogenically

Front 11

The earliest indication of a part or an organ during prenatal development is what?

Back 11

primordium

Front 12

What is the name for the period of the unattached conceptus, that takes place during the first week?

Back 12

preimplantation period of prenatal development

Front 13

At the beginning of the first week, a woman's ovum is penetrated by and united with a man's sperm during what?

Back 13

fertilization

Front 14

What is another name for egg?

Back 14

zygote

Front 15

The union of an ovum and sperm subsequently forms what?

Back 15

zygote

Front 16

During fertilization, the final stages of what occur in the ovum when the chromosomes of an egg and sperm come togehter?

Back 16

meiosis

Front 17

How many chromosomes are there when the sperm and ovum are joined?

Back 17

46

Front 18

What is another name for 46 chromosomes?

Back 18

diploid

Front 19

What is avoided with meiosis?

Back 19

excess chromosomes

Front 20

The photographic analysis of a person's chromosomes is done by orderly arrangement of pairs in a what?

Back 20

karyotype

Front 21

After fertilization, the zygote undergoes what, the division of cells?

Back 21

mitosis

Front 22

What is another name for individual cell division?

Back 22

cleavage

Front 23

After initial cleavage, the solid ball of cells is known as what?

Back 23

morula

Front 24

Because of the ongoing process of mitosis and secretion of fluid by the cells within the morula, the zygote becomes a vesicle known as a what?

Back 24

blastocyst

Front 25

When does mitosis take place?

Back 25

during growth and repair

Front 26

When does mitosis take place?

Back 26

during reproduction

Front 27

What is the embedding of a blasocyst into the endometrium?

Back 27

implantation

Front 28

What is the name for the layer of peripheral cells that the blastocyst consists of?

Back 28

trophoblast layer

Front 29

What is the small inner mass of embryonic cells in a blastocyst?

Back 29

embryoblast layer

Front 30

When a 21 chromosome is present what is the name for this?

Back 30

Down's Syndrome or Trisomy 21

Front 31

Implantation may occur outside the uterus, a condition called what?

Back 31

ectopic pregnancy

Front 32

Where do most ectopic pregnancies occur?

Back 32

fallopian tube

Front 33

What is the second period of prenatal development?

Back 33

embryonic period

Front 34

What is derived from the implanted blastocyst?

Back 34

embryo

Front 35

What processes cause the implanted blastocyst to become a embryo?

Back 35

induction, proliferation, differetiation, morphogenesis, and maturation

Front 36

What is the first physiological process involved in the beginning of most embryological development?

Back 36

induction

Front 37

What is the action of one group of cells on another that leads to the establishment of the developmental pathway in the responding tissue?

Back 37

induction

Front 38

What is controlled levels of cellular growth present during most of embryological development?

Back 38

proliferation

Front 39

Growth may be what, which occur from deep within a tissue or organ?

Back 39

interstitial

Front 40

Growth may be what, in which a tissue enlarges its size by the addition of layers on the outside of a structure?

Back 40

appositional

Front 41

What is a change in the embryonic cells, which are genetically identical but become quite distinct structurally and functionally?

Back 41

differentiation

Front 42

What is the development of different cell types?

Back 42

cytodifferentiation

Front 43

What is the development of different tissues whithin a structure?

Back 43

hisodifferentiation

Front 44

What is the development of the differing structure for each organ or system?

Back 44

morphodifferentiation

Front 45

What is the form of a structure?

Back 45

morphology

Front 46

What is the process of devlopment of specific tissue structure or shape?

Back 46

morphogenesis

Front 47

What is the from the migration of embryonic cells and inductive interactions of those cells?

Back 47

morphogenesis

Front 48

What begins during the later fetal period of the tissues and organs?

Back 48

maturation

Front 49

What is the name for the germ layers within a blastocyst?

Back 49

embryonic cell layers

Front 50

The increased embryonic cells in the second week of prenatal development creates what?

Back 50

embryonic cell layers

Front 51

What is developed from the blastocyst and appears as a flattened, essentially circular plate of bilayered cells?

Back 51

bilaminar embryonic disk

Front 52

The bilaminar disc as two layers, what are they?

Back 52

superior epiblast layer and inferior hypoblast layer

Front 53

What is bilaminar embryonic disc layer is composed of high columnar cells?

Back 53

superior epiblast layer

Front 54

What bilaminar embryonic disc layer is composed of small cuboidal cells?

Back 54

hypoblastt layer

Front 55

The bilamincar disc is suspended in the uterus's endometrium between what two fluid filled sacs?

Back 55

amniotic cavity and yolk sac

Front 56

What fluid filled cavity faces the epiblast layer?

Back 56

amniotic cavity

Front 57

What fluid filled cavity faces the hypblast layer?

Back 57

yolk sac

Front 58

What serves as inital nourishment for the embryonic disc?

Back 58

yolk sac

Front 59

What is a prenatal organ that joins the pregnant woman and devoloping embryo?

Back 59

placenta

Front 60

During the beginning of the third week of prenatal development, within the embryonic period, what forms within the bilaminar disc?

Back 60

primitive steak

Front 61

The primitive streak causes the bilaminar disc to have what, with a right half and left half?

Back 61

bilateral symmetry

Front 62

Migratory cells locate in the middle of the epiblast and hypoblast layers, becoming what, and embryonic connective tissue?

Back 62

mesenchyme

Front 63

Some of the mesenchymal cells creates a new embryonic layer called what?

Back 63

mesoderm

Front 64

With three layers present, the bilaminar disc has become thickened into a what?

Back 64

trilaminar embryonic disc

Front 65

With the creation of the mesoderm what does the embryonic layer and hypoblast layer become?

Back 65

ectoderm and endoderm

Front 66

The ectoderm gives rise to what?

Back 66

epidermis, nervous system, other structures

Front 67

The mesoderm gives rise to what?

Back 67

muscle coats, connective tissue, vessels supplying tissues and organs

Front 68

The endoderm gives rise to what?

Back 68

epithelial linings of the respiratory passages and digestive tract

Front 69

What is the name for the head end of the disc?

Back 69

cephalic end

Front 70

At the cephalic end, the what forms?

Back 70

oropharyngeal membrane

Front 71

The oropharyngeal membrane consists of what layers?

Back 71

ectoderm externally and endoderm internally

Front 72

What is the name for the tail end of the disc?

Back 72

caudal end

Front 73

At the caudal end, what forms?

Back 73

cloacal membrane

Front 74

What is the future location of the anus?

Back 74

cloacal end

Front 75

During the later part of the third week of prenatal development what begins to develop in the embryo?

Back 75

CNS

Front 76

What are the cells that are localized to the neural plate of the embryo?

Back 76

neuroectoderm

Front 77

What is the band of cells that extends the length of the embryo from the cephalic end to the caudal end?

Back 77

neural plate

Front 78

The neural plate undergoes further frowth and thickening, which cause it to deepen and invaginate centrally, forming what?

Back 78

neural groove

Front 79

Near the end of the third week, the neural groove deepens further and is surrounded by what?

Back 79

neural folds

Front 80

The neural folds meet superior to the neural groove, and what is formed during the 4th week?

Back 80

nueral tube

Front 81

The neural tube undergoes what at its most superior portion and forms the future spinal cord as well as other neural tissues?

Back 81

fusion

Front 82

During the 3rd week, what develop from the neuroectoderm?

Back 82

neural crest cells

Front 83

Many embryologist conder the neural crest cells to be what?

Back 83

4th embryonic layer

Front 84

The neural crest cells are essential in the development of what?

Back 84

face, neck, and oral tissues

Front 85

By the end of the 3rd week, the mesoderm additionally differentiates and begins to divide into paired cuboidal aggregate cells call what?

Back 85

somites

Front 86

During the 4th week of prenatal development, the disc undergoes what into an embyro, establishing for the first time the human axis and placing the tissues in their proper positions for further embryonic deelopment?

Back 86

embryonic folding

Front 87

The syndrome of what involves the abnormal development of one or more ectodermal structures?

Back 87

ectodermal dysplasia

Front 88

When do most congenital malformations occur?

Back 88

preimplantation period and embryonic period

Front 89

What are birth defects caused by the environment?

Back 89

teratogens

Front 90

What is the first period of prenatal development?

Back 90

preimplantation period

Front 91

What is the innermost lining of the uterus?

Back 91

prepared endometrium

Front 92

What is the ideal implantation site?

Back 92

back wall of the body of the uterus toward the spine

Front 93

The trophoblast gives rise to what?

Back 93

placenta

Front 94

What is the second period of prenatal development?

Back 94

embryonic period

Front 95

What is the action of one group of cells on another that leads to the establishment of the development pathway in the responding tissue?

Back 95

induction

Front 96

After the bilaminar disc is created, it is suspended in the uterus's endometrium between what?

Back 96

amniotic cavity and yolk sac

Front 97

What serves as initial nourishment for the embryonic disc?

Back 97

yolk sac

Front 98

What develops from the interactions of the trophoblast layer and endometrial layer?

Back 98

placenta

Front 99

What have the potential to proliferate and differentiate into diverse types of connective tissue-forming cells?

Back 99

mesenchymal cells

Front 100

The oropharyngeal membrane is the location of the future what?

Back 100

primitive mouth

Front 101

Embryonic folding occurs during what week?

Back 101

4th week

Front 102

Children with what syndrome ressemble little old men?

Back 102

ectodermal displasia

Front 103

Persons with what syndrome may suffer from partial or full anadontia?

Back 103

ectodermal displasia

Front 104

After folding of the disc, the endoderm lies inside what?

Back 104

ectoderm

Front 105

The anterior portion of the tube lined by endoderm is what?

Back 105

foregut

Front 106

What forms the primitive pharynx?

Back 106

foregut

Front 107

What are the two posterior portions of the tube lined by endoderm?

Back 107

midgut and foregut

Front 108

What do the midgut and hindgut form?

Back 108

laryngopharyn through the anal opening

Front 109

During development of the digestive tract, what form from evaginations on the lateral walls lining the pharynx?

Back 109

pharyngeal pouches

Front 110

What is the third period of prenatal development?

Back 110

fetal period

Front 111

The fetal period is a time of maturation of existing structures as the embryo enlarges to become what?

Back 111

fetus

Front 112

What is considered the most critical period of development?

Back 112

fetal period

Front 113

What is characterized by defects in the vertebral arches and various degress of disability?

Back 113

spina bifida

Front 114

What supplements are recommended during pregnancy to help prefent spina bifida, cleft lip and palate?

Back 114

folic acid

Front 115

What is the most common invasive prenatal diagnostic procedure?

Back 115

amniocentesis

Front 116

What is the yellow to yellow-brown statining of the teeth caused by antibiotics?

Back 116

tetracycline staining

Front 117

Tetracycline staining becomes chemically bound to what part of the tooth for life?

Back 117

dentin