Embryogenesis and Development

Question 1

joining of sperm and ovum

Answer 1

fertilization

Question 2

site fertilization usually occurs in the fallopian tube

Answer 2

ampulla

Question 3

uses acrosomal enzymes to penetrate the corona radiata and zona pellucida

Answer 3

sperm

Question 4

established by sperm when it contacts oocyte’s plasma membrane, then injects its pronucleus

Answer 4

acrosomal apparatus

Question 5

when sperm first penetrates it causes release of calcium ions preventing additional sperm from fertilizing the egg and increasing the metabolic rate of the resulting diploid zygote

Answer 5

cortical reaction

Question 6

result from fertilization of two eggs by two different sperm

Answer 6

fraternal (dizygotic) twins

Question 7

result from splitting of a zygote in two

Answer 7

identical (monozygotic) twins

Question 8

refers to early divisions of cell in embryo, result in more smaller cells, but no change in volume

Answer 8

cleavage

Question 9

what zygote becomes after first cleavage because it is no longer unicellular

Answer 9

embryo

Question 10

cleavage that results in cells capable of becoming any cell in organism

Answer 10

indeterminate cleavage

Question 11

cleavage that results in cells committed to differentiating into a specific cell type

Answer 11

determinate cleavage

Question 12

solid mass of cells seen in early development

Answer 12

morula

Question 13

has fluid filled center called blastocoel with two different structures: trophoblast (becomes placental structures) and inner cell mass (becomes the developing organism); implants in endometrial lining and forms the placenta

Answer 13

blastula (blastocyst)

Question 14

contains chorionic villi which penetrate endometrium and create interface between maternal and fetal blood

Answer 14

chorion

Question 15

supports embryo before placenta is established

Answer 15

yolk sac

Question 16

involved in early fluid exchange between embryo and yolk sac

Answer 16

allantois

Question 17

lies just inside chorion, produces amniotic fluid

Answer 17

amnion

Question 18

connects developing organism to placenta

Answer 18

umbilical cord

Question 19

archenteron is formed with a blastopore at the end, as archenteron grows through blastocoel it contacts opposite side establishing three primary germ layers

Answer 19

gastrulation

Question 20

becomes epidermis, hair, nails, and epithelia of nose, mouth, and anal canal, as well as nervous system and lens of eye

Answer 20

ectoderm

Question 21

becomes much of musculoskeletal, circulatory, and excretory systems, also gives rise to gonads and muscular and connective tissue layers of digestive and respiratory systems, as well as adrenal cortex

Answer 21

mesoderm

Question 22

becomes much of epithelial lining of respiratory and digestive tracts and parts of pancreas, thyroid, bladder, and distal urinary tracts

Answer 22

endoderm

Question 23

development of nervous system, begins after formation of germ layers

Answer 23

neuralation

Question 24

induces group of overlying ectodermal cells to form neural folds surrounding neural groove

Answer 24

notochord

Question 25

forms when neural folds fuse, becomes CNS

Answer 25

neural tube

Question 26

contained in tip of each neural fold, becomes PNS

Answer 26

neural crest cells

Question 27

substances that interfere with development

Answer 27

teratogens

Question 28

occurs as a result of determination and differentiation

Answer 28

cell specialization

Question 29

commitment to specific cell lineage, may be accomplished by uneven segregation of cellular material during mitosis or with morphogens (promote development down a specific line), cells must have competency to respond to a specific morphagen

Answer 29

determination

Question 30

changes a cell undergoes due to selective transcription to take on characteristics appropriate to its cell line

Answer 30

differentiation

Question 31

cells capable of developing into various cell types, classified by potency

Answer 31

stem cells

Question 32

able to differentiate into all cell types, including three germ layers and placental structures

Answer 32

totipotent cells

Question 33

able to differentiate into all three germ layers and their derivatives

Answer 33

pluripotent cells

Question 34

able to differentiate only into a specific subset of cell types

Answer 34

multipotent cells

Question 35

occurs through number of different signaling methods

Answer 35

cellular communication

Question 36

signaling method of cellular communication that releases factors to promote differentiation of a component responder

Answer 36

inducer

Question 37

signaling method of cellular communication where signals act on the same cell that released the signal

Answer 37

autocrine

Question 38

signaling method of cellular communication where signals act on local cells

Answer 38

paracrine

Question 39

signaling method of cellular communication where signals act through direct stimulation of adjacent cells

Answer 39

juxtacrine

Question 40

signaling method of cellular communication where signals act on distant tissues after traveling through the blood system

Answer 40

endocrine

Question 41

peptides that promote differentiation and mitosis in certain tissues

Answer 41

growth factors

Question 42

term for when two tissues both induce further differentiation in each other

Answer 42

reciprocal induction

Question 43

programmed cell death via formation of apoptotic blebs, can be used for sculpting certain anatomical structures

Answer 43

apoptosis

Question 44

ability of an organism to regrow certain parts of body

Answer 44

regenerative capacity

Question 45

result of multiple molecular and metabolic processes, including shortening of telomeres during cell division

Answer 45

senscence

Question 46

site of nutrient, gas, and waste exchange; serves endocrine functions, secreting estrogen, progesterone, and human chorionic gonadotropin (hCG)

Answer 46

plancenta

Question 47

serves as immune protection against many pathogens, antibodies are transferred from mother to child

Answer 47

placental barrier

Question 48

allow oxygen and carbon dioxide to be passively exchanged

Answer 48

concentration gradients

Question 49

has higher affinity for oxygen than adult hemoglobin (HbA), affinity assists in transfer and retention of oxygen into fetal circulatory system

Answer 49

fetal hemoglobin (HbF)

Question 50

carry deoxygenated blood from the fetus to the placenta

Answer 50

umbilical arteries

Question 51

carries oxygenated blood from placenta back to the fetus

Answer 51

umbilical vein

Question 52

differs from adult version by having three shunts

Answer 52

fetal circulatory system

Question 53

fetal circulatory system: | connects right atrium to left atrium, bypassing lungs

Answer 53

foramen ovale

Question 54

fetal circulatory system: | connects pulmonary artery to aorta, bypassing lungs

Answer 54

ductus arteriosis

Question 55

fetal circulatory system: | connects umbilical vein to inferior vena cava, bypassing liver

Answer 55

ductus venosus

Question 56

when organogenesis occurs during pregnancy (development of heart, eyes, gonads, limbs, liver, brain)

Answer 56

first trimester

Question 57

when tremendous growth occurs, movement begins, face becomes distinctly human, and digits elongate during pregnancy

Answer 57

second trimester

Question 58

when rapid growth and brain development continue and transfer of antibodies to fetus during pregnancy

Answer 58

third trimester

Question 59

cervix thins out, amniotic sac ruptures; uterine contractions (coordinated by prostaglandins and oxytocin) result in birth of fetus; placenta and umbilical cord are expelled

Answer 59

birth