Deck 29: Development,growth,aging,and Genetics

Question 1

The inner cell mass of the blastocyst

A)consists of yolk-filled storage cells.
B)contains cells that will form the embryo.
C)represents the future placenta.
D)will form the zona pellucida.
E)contains cells that are discarded.

Answer 1

B

Question 2

When the embryonic mass of cells develops an internal cavity,the mass of cells is called a(n)

A)zygote.
B)morula.
C)blastocyst.
D)embryonic disc.
E)trophoblast.

Answer 2

C

Question 3

The placenta plays an important role in

A)implantation.
B)onset of lactation.
C)beginning of parturition.
D)provision of nutrients to the fetus.
E)insulating the fetus.

Answer 3

D

Question 4

The placenta and membranes surrounding the embryo develop from the

A)morula.
B)blastocyst.
C)trophoblast.
D)inner cell mass.
E)blastocele.

Question 5

If a woman ovulates two oocytes and both are fertilized,

A)identical twins result.
B)fraternal twins result.
C)Siamese twins result.
D)monozygotic twinning occurs.
E)paternal twins result.

Question 6

The prenatal period during which the major organ systems form is the

A)fetal period.
B)germinal period.
C)embryonic period.
D)neonatal period.

Question 7

Once the embryonic mass has 12 or more cells,it is called a

A)morula.
B)gastrula.
C)blastula.
D)blastocyst.
E)trophoblast.

Question 8

Fusion of the male and female pronuclei forms the

A)blastocyst.
B)morula.
C)zygote.
D)gastrula.
E)trophoblast.

Question 9

The clinical age of the unborn child is calculated from

A)ovulation.
B)conception.
C)the last menstrual period.
D)fourteen days after the last menstrual period.
E)fourteen days before the last menstrual period.

Question 10

At the time of implantation,the human embryo is in a stage of development known as the

A)fetus.
B)zygote.
C)morula.
D)blastocyst.
E)egg.

Question 11

Developmental events are calculated from

A)ovulation.
B)conception.
C)the last menstrual period.
D)fourteen days after the last menstrual period.
E)fourteen days before the last menstrual period.

Question 12

What event separates childhood from adolescence?

A)puberty
B)infancy
C)formation of germ layers
D)beginning to walk

Question 13

An embryonic cell that contains the potential to give rise to any tissue type is called a/an

A)differentiated cell.
B)multipotent cell.
C)pluripotent cell.
D)omnipotent cell.
E)totipotent cell.

Question 14

Fusion of the male and female pronuclei

A)results in an oocyte forming.
B)restores the diploid number of chromosomes.
C)occurs before ovulation.
D)results in a haploid cell forming.
E)results in a total of 23 chromosomes.

Question 15

Germ layers form during the ____ period while organ systems mature during the ____ period.

A)embryonic; fetal
B)prenatal; neonatal
C)germinal; embryonic
D)germinal; fetal
E)fetal; germinal

Question 16

An embryonic cell that has the potential to develop into a wide range of tissues is called a/an

A)differentiated cell.
B)multipotent cell.
C)pluripotent cell.
D)omnipotent cell.
E)totipotent cell.

Question 17

Depolarization of the oocyte plasma membrane occurs when the first sperm attaches to the integrin $\alpha$ 6 $\beta$ 1.This is called the

A)slow block to polyspermy.
B)acrosomal reaction.
C)fast block to polyspermy.
D)fertilization.
E)spermiogenesis.

Question 18

If the zygote splits into two separate cells,

A)identical twins result.
B)fraternal twins result.
C)dizygotic twinning occurs.
D)both cells die.
E)paternal twins result.

Question 19

The single layer of cells that surrounds the blastocele is the

A)morula.
B)gastrula.
C)blastocyst.
D)trophoblast.
E)inner cell mass.

Question 20

The period from conception until birth is

A)the prenatal period.
B)the germinal period.
C)the embryonic period.
D)the fetal period.
E)the conceptual period.

Question 21

Which of the following statements about the syncytiotrophoblast is false?

A)It forms the developing embryo.
B)It is composed of a non-dividing,multinucleated cell.
C)It is nonantigenic,so that it triggers no immune response.
D)It invades the maternal tissues that compose the endometrium of the uterus.
E)It forms lacunae.

Question 22

Which germ layer is the epidermis derived from?

A)ectoderm
B)mesoderm
C)endoderm

Question 23

Where does implantation normally occur?

A)in the fundus area of the uterus
B)in the isthmus area of the uterine tube
C)in the cervix area of the uterus
D)in the infundibulum area of the uterine tube

Question 24

Through what structure do epiblast cells migrate to form the mesoderm?

A)lacunae
B)chorionic villi
C)hypoblast
D)primitive streak
E)blastocele

Question 25

Which germ layer is most muscle derived from?

A)ectoderm
B)mesoderm
C)endoderm

Question 26

Which of the following organ systems is derived from all three germ layers?

A)nervous
B)cardiovascular
C)endocrine
D)integumentary
E)skeletal

Question 27

The cytotrophoblast

A)forms the chorionic villi.
B)replaces the syncytiotrophoblast.
C)remains throughout development.
D)forms branches that protrude into the amniotic cavity.
E)is not an embryonic part of the placenta.

Question 28

Placenta previa occurs when

A)a normally placed placenta tears away from the uterine wall.
B)the placenta is formed too early.
C)implantation occurs close to the cervix.
D)implantation occurs in the fundus of the uterus.

Question 29

The embryonic disk is initially composed of

A)ectoderm and hypoblast.
B)epiblast and mesoderm.
C)epiblast and hypoblast.
D)hypoblast and yolk sac.
E)epiblast and yolk sac.

Question 30

Which of the following is derived from endoderm?

A)brain
B)muscle
C)epidermis of the skin
D)lining of the digestive tract
E)cardiovascular system

Question 31

The time period between fertilization and implantation is approximately

A)5 days.
B)7 days.
C)10 days.
D)14 days.
E)21 days.

Question 32

Which germ layer is the thyroid derived from?

A)ectoderm
B)mesoderm
C)endoderm

Question 33

Which germ layer is the thymus derived from?

A)ectoderm
B)mesoderm
C)endoderm

Question 34

Gastrulation is the process of development that produces the

A)placenta.
B)embryonic disk.
C)germ layers.
D)rudimentary organs.

Question 35

The chorionic villi

A)form from branches of the syncytiotrophoblast cords.
B)increase surface area of the amniotic cavity.
C)contribute to the formation of the placenta.
D)are necessary for implantation to occur.
E)are not part of the placental formation.

Question 36

Damage to the mesoderm during embryological development would affect the formation of the

A)thyroid.
B)brain.
C)heart.
D)teeth.
E)urinary bladder.

Question 37

Which of the following is formed from mesoderm?

A)autonomic neurons
B)dermis of the skin
C)adrenal medulla
D)teeth
E)tonsils

Question 38

The embryonic membrane that completely encloses the embryo in a watery sac is the

A)yolk sac.
B)amnion.
C)allantois.
D)chorion.
E)ectodermal sac.

Question 39

Some epiblast cells migrate and emerge between the epiblast and endoderm as a new germ layer called the

A)yolk sac.
B)mesoglia.
C)notochord.
D)mesoderm.
E)primitive streak.

Question 40

Which of the following is derived from ectoderm?

A)lens of the eye
B)thymus gland
C)tonsils
D)urinary bladder
E)dermis of skin

Question 41

Arm and legs buds appear at about 28 days from

A)the coelom.
B)apical ectodermal ridges.
C)somitomeres.
D)neural crest cells.

Question 42

Which germ layer is the urinary bladder derived from?

A)ectoderm
B)mesoderm
C)endoderm

Question 43

Arrange the following in the sequence in which they form in the embryo. (1)neural plate
(2)neural tube
(3)notochord
(4)primitive streak

A)1,2,3,4
B)1,3,2,4
C)4,3,1,2
D)4,1,3,2
E)3,4,1,2

Question 44

Which of the following is NOT a possible route for neural crest cells?

A)melanocytes
B)autonomic ganglion neurons
C)adrenal cortex
D)sensory ganglia
E)enteric nervous system neurons

Question 45

Which germ layer is the brain and spinal cord derived from?

A)ectoderm
B)mesoderm
C)endoderm

Question 46

The pleural and peritoneal cavities of the adult begin as part of the _____ cavity.

A)cloacal
B)somatomeric
C)coelomic
D)apical
E)ventral

Question 47

Which germ layer are the tonsils derived from?

A)ectoderm
B)mesoderm
C)endoderm

Question 48

If the secondary palate does not fuse the result is a

A)cleft palate.
B)cleft throat.
C)facial cleft.
D)cleft lip.
E)cleft tongue.

Question 49

Cells of the neuroectoderm become all of the following EXCEPT the

A)brain
B)spinal cord
C)postganglionic autonomic neurons
D)posterior pituitary gland

Question 50

Which germ layer is tooth enamel derived from?

A)ectoderm
B)mesoderm
C)endoderm

Question 51

Somites give rise to

A)nerves.
B)blood.
C)glands.
D)muscles.
E)spinal cord.

Question 52

Segments of mesoderm that will form muscles are

A)mesonephros.
B)mandibular processes.
C)neural tube.
D)secondary palate.
E)somites.

Question 53

The embryo is most sensitive to outside influences that can cause malformations during the

A)first two weeks after fertilization.
B)third to the ninth weeks of development.
C)ninth to the sixteenth weeks of development.
D)twelfth to the twentieth weeks of development.
E)twenty-first to twenty-sixth week of development.

Question 54

The allantois enlarges to form the

A)kidney.
B)gonads.
C)ureter.
D)urinary bladder.
E)urethra.

Question 55

Which of the following organs develops from evaginations along the early digestive tract?

A)heart
B)adrenal medulla
C)lungs
D)nasal cavity
E)kidneys

Question 56

Which of the following structures is NOT involved in the formation of the face?

A)apical ectodermal ridges
B)frontonasal process
C)maxillary processes
D)mandibular processes

Question 57

The oropharyngeal and cloacal membranes,when opened,allow the _____ to open to the outside.

A)liver
B)skin
C)lungs
D)digestive tract
E)ears

Question 58

Which germ layer are the bones (except facial)derived from?

A)ectoderm
B)mesoderm
C)endoderm

Question 59

A cleft lip results when

A)the two halves of the secondary palate do not fuse.
B)the frontonasal and maxillary processes do not fuse.
C)the lateral edges of the nasal placodes do not fuse with the maxillary processes.
D)the maxillary processes do not fuse with the mandibular processes.
E)None of these choices is correct.

Question 60

Which germ layer is the cardiovascular system derived from?

A)ectoderm
B)mesoderm
C)endoderm

Question 61

Which of the following statements concerning musculoskeletal system development is true?

A)Skeletal muscles develop from crest cells.
B)Myoblasts produce somites.
C)The vertebral column develops from somite-derived mesoderm.
D)Enlargement of muscles after birth is due to an increase in the number of muscle fibers.
E)Ossification ends before birth.

Question 62

The lungs develop from

A)somitomeres.
B)neural crest cells.
C)an evagination from the foregut.
D)an evagination from the floor of the diencephalon.
E)an invagination from the hindgut.

Question 63

Which of the following statements concerning the embryonic circulatory system is true?

A)The heart develops from four endothelial tubes.
B)Blood vessels form from blood islands.
C)An opening in the interatrial septum is called the sinus venosus.
D)The bulbus cordis becomes the sinoatrial node (the adult pacemaker).
E)There is an opening in the interventricular septum.

Question 64

Organogenesis is generally completed by day _____ of development.

A)20
B)30
C)45
D)60
E)75

Question 65

Failure of the neural tube to close in the region of the head results in

A)anencephaly.
B)ventricular enlargement.
C)cleft palate.
D)soft spots on the skull.
E)hydrocephaly.

Question 66

What structure forms the lower jaw?

A)mesonephros
B)mandibular processes
C)neural tube
D)secondary palate
E)somites

Question 67

The opening that connects the right and left atria in the fetal heart is the

A)interatrial septum.
B)septum primum.
C)septum secundum.
D)foramen ovale.
E)foramen rotundum.

Question 68

Which gland is formed by an evagination from the floor of the diencephalon?

A)anterior pituitary gland
B)posterior pituitary gland
C)thyroid gland
D)adrenal glands
E)pancreas

Question 69

The central cavity of the neural tube becomes the

A)cerebrum.
B)mid-brain.
C)cranial cavity.
D)ventricles of the brain.
E)epidural space.

Question 70

Which of the following statements concerning development of the integumentary system is true?

A)The epidermis is derived from mesoderm.
B)The melanocytes are derived from ectoderm.
C)Nails,hair,and glands develop from the dermis.
D)Sensory receptors in the skin are derived from the epidermis.
E)Collagen fibers do not appear until after birth.

Question 71

What is formed by closure of neural groove?

A)mesonephros
B)mandibular processes
C)neural tube
D)secondary palate
E)somites

Question 72

Which gland develops from an evagination of the ectoderm in the roof of the embryonic oral cavity?

A)anterior pituitary gland
B)posterior pituitary gland
C)thyroid gland
D)adrenal glands
E)pancreas

Question 73

The embryonic heart

A)develops from two endothelial tubes that fuse together.
B)consists of four chambers.
C)has two atria but only one ventricle.
D)doesn't beat until just prior to birth.
E)has no passages connecting right side to left side.

Question 74

What structure forms the roof of the mouth?

A)mesonephros
B)mandibular processes
C)neural tube
D)secondary palate
E)somites

Question 75

The adult kidney develops from the

A)pronephros.
B)metanephros.
C)mesonephros.
D)allantois.
E)neonephros.

Question 76

Which gland is derived from both neural crest cells and mesoderm?

A)anterior pituitary gland
B)posterior pituitary gland
C)thyroid gland
D)adrenal glands
E)pancreas

Question 77

The eyes develop as an evagination from the

A)myelencephalon.
B)mesencephalon.
C)neural crest cells.
D)diencephalon.
E)telencephalon.

Question 78

The olfactory bulbs and nerves develop as an evagination from the

A)myelencephalon.
B)mesencephalon.
C)neural crest cells.
D)diencephalon.
E)telencephalon.

Question 79

Which of the following structures originates as an evagination from the floor of the pharynx,moves into the neck,and loses its connection with the pharynx?

A)pancreas
B)thyroid gland
C)adrenal medulla
D)adenohypophysis
E)parathyroid glands

Question 80

Which gland originates as two evaginations from the duodenum?

A)anterior pituitary gland
B)posterior pituitary gland
C)thyroid gland
D)adrenal glands
E)pancreas