Deck 28: Embryology and Human Development

Question 1

Each germ layer develops into specific structures. The nervous system develops from the ________.

A) ectoderm
B) mesoderm
C) endoderm

Answer 1

A

Question 2

After oocyte activation and completion of meiosis, the female nuclear material reorganizes as the ________.

A) syncytiotrophoblast
B) female pronucleus
C) cytotrophoblast
D) male pronucleus
E) primary oocyte

Answer 2

B

Question 3

Human sex cells are called ________.

A) spores
B) histones
C) genes
D) gonads
E) gametes

Answer 3

E

Question 4

If two sperm penetrate two different oocytes, the two resulting offspring would be ________.

A) identical twins
B) one male and one female
C) fraternal twins
D) two males
E) There is not enough information to answer the question.

Question 5

Because of the great loss of spermatozoa during the process of traveling from the vagina to the ampulla of the uterine tube where fertilization occurs, a male must have at least ________ spermatozoa per milliliter, or he will be functionally sterile.

A) 10,000
B) 100,000
C) 2,000,000
D) 20,000,000
E) 500,000,000

Question 6

Sperm cannot perform fertilization until they ________.

A) undergo activation
B) undergo capacitation
C) lose their acrosome
D) are in the vagina for three days
E) All of the answers are correct.

Question 7

The blastodisc of the early embryo consists of the ________.

A) hypoblast and the epiblast
B) hypoblast and the trophoblast
C) epiblast and the trophoblast
D) hypoblast and the cytotrophoblast
E) cytotrophoblast and the epiblast

Question 8

The amnionic cavity is filled with fluid, which functions to ________.

A) cushion the developing embryo or fetus
B) allow fluid to enter the placenta
C) form the plasma portion of the blood
D) give the embryo nourishment
E) permit implantation to occur

Question 9

The process by which cells specialize during development is ________.

A) differentiation
B) implantation
C) meiosis
D) embryology
E) None of the answers are correct.

Question 10

The collective term for embryonic and fetal development is ________.

A) preembryonic development
B) prenatal development
C) postnatal development
D) gestation
E) fertilization

Question 11

The time spent in prenatal development is called ________.

A) gestation
B) embryology
C) spermatogenesis
D) atresia
E) None of the answers are correct.

Question 12

The series of progressive changes of anatomical structures from conception to maturity is referred to as ________.

A) growth
B) gestation
C) development
D) differentiation
E) None of the answers are correct.

Question 13

From which germ layer are muscles derived?

A) ectoderm
B) mesoderm
C) endoderm

Question 14

Fusion of the male and female pronuclei forming the zygote is known as ________.

A) meiosis
B) gamete formation
C) penetration
D) fertilization
E) amphimixis

Question 15

From which germ layer is the epidermis of the skin derived?

A) ectoderm
B) mesoderm
C) endoderm

Question 16

There are two protective layers around the secondary oocyte, the zona pellucida and the ________.

A) second polar body
B) transverse membrane
C) corona radiata
D) acrosome
E) first polar body

Question 17

The embryonic development stage occurs during the ________.

A) first three weeks of development
B) third through the eighth week of development
C) eighth through the twenty-fourth week of development
D) last eight weeks of development
E) just before childbirth

Question 18

In what developmental stage does the human embryo implant in the wall of the uterus?

A) as a zygote
B) in the morula stage
C) in the blastocyst stage
D) in the gastrula stage
E) during organogenesis

Question 19

From which germ layer is the dermis of the skin derived?

A) ectoderm
B) mesoderm
C) endoderm

Question 20

Fertilization is the process whereby ________.

A) two haploid gametes fuse
B) two polar bodies fuse to produce a zygote
C) two diploid gametes join and recombine genetically
D) the cells of a newly produced embryo divide
E) None of the answers are correct

Question 21

The connection between the embryo and the chorion is the ________.

A) umbilical cord
B) yolk stalk
C) body stalk
D) capsular decidua
E) basal decidua

Question 22

Once cleavage starts, the zygote starts dividing, forming cells called ________.

A) morulas
B) blastomeres
C) blastocytes
D) differentiated
E) blastocysts

Question 23

What happens during gastrulation?

A) The three primary germ layers are formed.
B) The embryo implants in the wall of the uterus.
C) The placenta becomes functional.
D) The chorion disintegrates.
E) The amnionic fluid appears.

Question 24

The mesoderm associated with the allantois spreads to cover the entire inside of the trophoblast. This combination of mesoderm and trophoblast is the ________.

A) chorion
B) allantois
C) mesoderm
D) blastodisc
E) yolk sac

Question 25

The inner cavity of the blastocyst is called the ________.

A) allantois
B) blastocoele
C) cytotrophoblast
D) lacuna
E) primary villus

Question 26

In the early blastocyst, the placenta will develop from the ________.

A) blastocoele
B) trophoblast
C) inner cell mass
D) morula
E) None of the answers are correct.

Question 27

The ________ is a hollow ball of cells.

A) blastocyst
B) gastrula
C) morula
D) embryo
E) None of the answers are correct.

Question 28

The cavity separating the inner cell mass from the trophoblast is the ________.

A) blastocoele
B) amniotic cavity
C) lacuna
D) epiblast
E) hypoblast

Question 29

The process termed ________ begins when the blastocyst attaches to the endometrium and continues as the blastocyst invades maternal tissues.

A) cleavage
B) implantation
C) placentation
D) differentiation
E) embryogenesis

Question 30

The ________ is the site of early blood cell formation.

A) trophoblast
B) blastocoele
C) amnion
D) allantois
E) yolk sac

Question 31

The first of the extraembryonic membranes to appear, which ultimately becomes involved in blood cell formation, is the ________.

A) amnion
B) allantois
C) chorion
D) yolk sac
E) None of the answers are correct.

Question 32

Formation of the germ layers results from the process of ________.

A) meiosis
B) somite formation
C) blastolation
D) gastrulation
E) None of the answers are correct.

Question 33

The germ layer of the embryo that is in contact with the amniotic cavity is the ________.

A) mesoderm
B) endoderm
C) ectoderm
D) hypoblast
E) epiblast

Question 34

Collectively, the yolk sac, chorion, amnion, and allantois are called the ________.

A) supra-embryonic membranes
B) pre-fetal mass
C) extra-embryonic membranes
D) inter-embryonic membranes
E) None of the answers are correct.

Question 35

Neural crest cells give rise to ________.

A) melanocytes of the skin
B) adrenal medullae
C) Schwann cells
D) laryngeal cartilages
E) All of the choices are correct.

Question 36

At about day nine of development of the blastocyst, the cells of the inner cell mass are organized into an oval sheet that is two layers thick, called the ________.

A) amnion
B) yolk sac
C) endoderm
D) blastodisc
E) None of the answers are correct.

Question 37

During implantation, the developing blastocyst receives nutrients from the nutrients released from the disruption and enzymatic digestion of ________.

A) placenta
B) chorion
C) endometrial glands
D) cytotrophoblast
E) None of the answers are correct.

Question 38

The chorion forms from the ________.

A) inner cell mass
B) placenta
C) trophoblast
D) ectoderm
E) endoderm

Question 39

The extraembryonic membrane that persists as part of the urinary bladder is the ________.

A) allantois
B) chorion
C) yolk sac
D) amnion
E) None of the answers are correct.

Question 40

Burrowing of the embryo into the endometrium is called ________.

A) impregnation
B) permeation
C) implantation
D) fertilization
E) None of the answers are correct.

Question 41

During the first trimester of development, the basis for organ formation is established. This process is called ________.

A) embryogenesis
B) organogenesis
C) implantation
D) gastrulation
E) None of the answers are correct.

Question 42

A premature infant often is able to survive if born ________.

A) in the first trimester
B) in the third trimester
C) in the second trimester
D) during the embryonic stage
E) None of the answers are correct.

Question 43

A typical healthy neonatal heart rate is ________ beats per minute.

A) 60-80
B) 80-100
C) 100-120
D) 120-140
E) 140-160

Question 44

The fetus gains the greatest amount of weight during ________.

A) the first three weeks of the second trimester
B) the entire third trimester
C) the entire second trimester
D) Weight gain is evenly distributed throughout all of the stages of development.
E) None of the answers are correct.

Question 45

Surgical cutting of the perineum during delivery is called ________.

A) vasectomy
B) tubal ligation
C) episiotomy
D) vagectomy
E) None of the answers are correct.

Question 46

Problems with the formation of the chorion would affect ________.

A) the embryo's ability to produce blood cells
B) formation of the limbs
C) the embryo's ability to derive nutrition from the mother
D) lung formation
E) None of the answers are correct.

Question 47

Full term in pregnancy is usually lasts for________.

A) 5 months
B) 9 months
C) 12 months
D) 18 months
E) None of the answers are correct.

Question 48

The ________ stage begins with the onset of true labor, as the cervix dilates and the fetus begins to move down the cervical canal.

A) dilation
B) expulsion
C) placental

Question 49

In a ________ birth, the baby's buttocks or legs are delivered before the head.

A) premature
B) cesarean
C) breech
D) frontal
E) None of the answers are correct.

Question 50

During the second trimester, the organ systems ________.

A) will not change significantly in size, but will become functional
B) of the placenta will grow much faster than the embryo itself
C) will complete their functional development
D) will not continue functional development, but will increase greatly in size
E) None of the answers are correct.

Question 51

Surgical incision of the abdominal wall to remove the fetus is called a(n)________.

A) episiotomy
B) breech birth
C) abortion
D) cesarean section
E) parturition

Question 52

The dilation stage of labor ________.

A) occurs about an hour after the onset of true labor
B) includes dilation of the cervix
C) usually is short-a few minutes in length
D) has contractions of the uterus spread only a few minutes apart
E) All of the answers are correct.

Question 53

The relatively thin portion of the endometrium that covers the embryo and separates it from the uterine cavity is called the ________.

A) parietal decidua
B) placenta
C) basal decidua
D) villi
E) capsular decidua

Question 54

The first month of life after delivery is the ________ period.

A) fetal
B) neonatal
C) postpartal
D) embryonic
E) afterbirth

Question 55

During the ________ stage of labor, the muscle tension builds in the walls of the partially empty uterus, and the organ gradually decreases in size.

A) dilation
B) expulsion
C) placental

Question 56

Which time period is the most dangerous in prenatal life?

A) first trimester
B) second trimester
C) third trimester
D) labor
E) None of the answers are correct.

Question 57

The muscular activity that forcibly expulses the fetus from the uterus is called ________.

A) development
B) labor
C) parturition
D) placental expulsion
E) None of the answers are correct.

Question 58

Dilation, expulsion, and placental are the three stages of ________.

A) pregnancy
B) fetal development
C) trimesters
D) labor
E) delivery

Question 59

Developmental events that occur during the second trimester include ________.

A) development of hair and sebaceous glands
B) development of sweat glands
C) keratin and nail production
D) myelination of the spinal cord
E) All of the answers are correct.

Question 60

Which of the following changes occur during the third trimester?

A) Completion of pulmonary branching and alveolar formation.
B) Formation of the plicae of the intestines.
C) Completion of the formation of the nephrons.
D) In male fetuses, the testes descend.
E) All of the answers are correct.

Question 61

The neural groove becomes the notochord.

Question 62

The foramen ovale is actually an opening in the ________.

A) interventricular septum
B) interatrial septum
C) ventricular wall
D) ductus arteriosus
E) fossa ovalis

Question 63

A neonatal condition resulting from maternal alcohol consumption; characterized by developmental defects is called sudden infant death syndrome.

Question 64

In the axial skeleton, most muscle, cartilage, and connective tissues are derived from a series of mesenchymal blocks called ________.

A) teratogens
B) dermatomes
C) notochords
D) lateral plates
E) somites

Question 65

When implantation begins, the trophoblastic cells of the blastocyst are responsible for providing food to the developing embryo.

Question 66

Muscle are the result of maturing ________.

A) myotomes
B) sclerotomes
C) notochord
D) mesoderm
E) apical ridges

Question 67

White matter of the spinal cord develops from the ________.

A) notochord
B) neuroepithelial layer
C) mantle layer
D) marginal layer
E) neurocoel

Question 68

Which of the following is the condition of the skull at birth?

A) Only the chondrocranium exists.
B) The floor and roof of the cranium are incomplete.
C) The frontal bone has just begun forming.
D) The mandible is incomplete.
E) Only the roof of the skull remains incomplete.

Question 69

In the process of development, a human being forms in the womb for about 9 months and grows to maturity in 15 to 20 years.

Question 70

During the initial stages of fertilization, sperm release hyaluronidase from their acrosome, which breaks down the bonds between adjacent follicle cells.

Question 71

Neural tube formation occurs when the neural folds close and lose their connection with the superficial ectoderm.

Question 72

The two systems with related functions that will change the most rapidly at birth, but that are still undergoing some differentiation shortly before birth, are the circulatory and ________ systems.

A) cardiovascular
B) integumentary
C) reproductive
D) digestive
E) respiratory

Question 73

Formation of the neural tube ________.

A) begins at the anterior (head) end and proceeds toward the posterior (tail)
B) begins at the posterior and proceeds toward the anterior
C) begins in the middle and proceeds toward the head and the tail
D) is random in that it can begin and proceed at any location along the neural plate
E) is caused by compaction of the neural plate

Question 74

The last systems to complete prenatal development are the ________.

A) renal and circulatory
B) nervous and digestive
C) renal and respiratory
D) muscular and nervous
E) None of the answers are correct.

Question 75

The first part of the nervous system to form is the ________.

A) cerebrum
B) neural tube
C) spinal cord
D) brain stem
E) None of the answers are correct.

Question 76

The heart begins pumping and circulating blood in the ________ week.

A) first
B) third
C) fifth
D) eighth
E) tenth

Question 77

The neural plate is the first stage of development in the nervous system.

Question 78

Which of the following forms the nucleus pulposus?

A) mesoderm
B) somites
C) neural arch
D) notochord
E) sclerotomes

Question 79

Anything that disrupts normal development by causing cell or chromosome damage or altering the chemical environment of the embryo is called a teratogen.

Question 80

Pharyngeal pouch III becomes the upper portions of the parathyroid and thymus glands.