1. Chapter 29:1-5 Development and Inheritance
Dr. Ronald J. Santangelo
MSHAPI-ITP
Final Project
Week 1
December 10, 2016
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

2. 29:1 Development, various stages, continuous process, fertilization-maturity
Learning Outcomes
Explain relationship between differentiation & development
Specify various stages of development
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

3. Page 1096
Development -gradual modification of anatomical structures & physiological characteristics from conception to maturity. The formation of different types of cells is differentiation.
Prenatal development -occurs before birth: postnatal development begins at birth to maturity, when aging begins. Inheritance transfer of genetically determined characteristics from generation to generation. Genetics is the study of mechanisms of inheritance.
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

4. Check Point Define differentiation.
What event marks the onset of development?
Define inheritance.
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

5. Review Video

6. 29:2 Fertilization-secondary oocyte & spermatozoon forms zygote
Learning Outcomes
Describe the process of fertilization.
Explain how developmental processes are regulated
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

7. Page 1097
Fertilization/ conception-normally in uterine tubes within day after ovulation. Spermatozoa can’t fertilize secondary oocyte until under going capacitation
Acrosomes of spermatozoa release hyaluronidase & acrosin enzymes required for corona radiate & zona pellucida penetration of oocyte. Single spermatozoon contacts oocyte membrane fertilization begins & oocyte activation follows.
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

8. Figure 29-1b Fertilization (Part 1 of 6).
Oocyte at Ovulation
Ovulation releases a secondary oocyte and the first polar body; both are surrounded by the corona radiata. The oocyte is suspended in metaphase of meiosis II.
Corona
radiata
First polar
body
Zona
pellucida

9. Fertilization and Oocyte Activation Acrosomal enzymes from multiple
Figure 29-1b Fertilization (Part 2 of 6). 1
Fertilization and Oocyte Activation
Acrosomal enzymes from multiple
sperm create gaps in the corona
radiata. A single sperm then makes
contact with the oocyte membrane,
and membrane fusion occurs,
triggering oocyte activation and
the completion of meiosis.
Second
polar
body
Fertilizing
spermatozoon
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

10. Pronucleus Formation Begins The sperm is absorbed into the
Figure 29-1b Fertilization (Part 3 of 6). 2
Pronucleus Formation Begins
The sperm is absorbed into the
cytoplasm, and the female
pronucleus develops.
Nucleus of
fertilizing
spermatozoon
Female
pronucleus
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

11. Page 1097
During activation oocyte completes meiosis II becoming functional mature ovum. Polyspermy prevented by membrane depolarization & the cortical reaction.
After activation, female pronucleus & male pronucleus fuse in process called amphimixis
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

12. The male pronucleus develops, and spindle fibers appear in preparation
Figure 29-1b Fertilization (Part 4 of 6). 3
Spindle Formation and
Cleavage Preparation
The male pronucleus develops, and
spindle fibers appear in preparation
for the first cleavage division.
Male
pronucleus
Female
pronucleus
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

13. Cleavage Begins-zygote 46 chromosomes
Figure 29-1b Fertilization (Part 5 of 6). 4
Amphimixis Occurs and
Cleavage Begins-zygote
46 chromosomes
Metaphase of first
cleavage division
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

14. The first cleavage division nears completion about 30 hours after
Figure 29-1b Fertilization (Part 6 of 6). 5
Cleavage Begins
The first cleavage division nears
completion about 30 hours after
fertilization.
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Blastomeres

15. Check Point
Name two sperm enzymes important to secondary oocyte penetration.
How many chromosomes are contained within a human zygote?
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

16. You Tube https://www.youtube.com/watch?v=7G2rL5Cutd4
Review Video
You Tube

17. 29:3 Gestation 3 stages prenatal development
Learning Outcomes
List the 3 stages of prenatal development
Describe the major events in each stage
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

18. 3 stages of prenatal development
1st Trimester -period of embryonic & early fetal development, major organs appear
2nd Trimester –dominated by organs and organ system development, near completion by end of month 6, body shape & proportions change, looks distinctively human
3rd Trimester –rapid fetal growth & adipose deposition early 3rd major organs fully functional, 1 or 2 months premature birth has reasonable survival rate
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

19. Check Point Define gestation.
Characterize key features of each trimester/ stage of fetal development.
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

20. You Tube https://www.youtube.com/watch?v=zasjMiQjvr0
Review Video
You Tube

21. 29:4 Cleavage, implantation & embryogenesis critical events in 1st trimester
Learning Outcomes
Explain how 3 germ layers are involved in forming the embryonic membranes.
Discuss the importance of the placenta as an endocrine organ.
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

22. 1st Trimester
Cleavage - zygote becomes pre-embryonic develops into blastocyst (multicellular complex), ends with contact of uterine wall
Implantation –begins with blastocyst attachment to endometrium, invade maternal tissue, stages formation of vital embryonic structures
Placentation -formation of blood vessels around blastocyst. Placenta organ permitting change between maternal and embryonic blood. Forms, supports & expelled from uterus
Embryogenesis –vital embryo formation, establishes foundation for all major organ systems
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

23. Blastomeres form blastocyst a hollow ball w/ inner cavity know as blastocoele
Polar
bodies
4-cell stage
2-cell stage
DAY 1
DAY 2
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
First cleavage
division
DAY 0:
Fertilization
Figure 29-2 Cleavage and Blastocyst Formation (Part 1 of 2).

24. Inner cell mass Blastocyst
Figure 29-2 Cleavage and Blastocyst Formation (Part 2 of 2).
Zona
pellucida
Early morula
DAY 3
Advanced
morula
DAY 4
Hatching
Inner cell
mass
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
DAY 6
Days 7–10:
Implantation in
uterine wall
(see Figure 29–3)
Blastocoele
Blastocyst
Trophoblast

25. DAY 6 FUNCTIONAL ZONE UTERINE OF ENDOMETRIUM CAVITY Uterine glands
Figure 29-3 Stages in Implantation (Part 1 of 2).
DAY 6
FUNCTIONAL ZONE
OF ENDOMETRIUM
UTERINE
CAVITY
Uterine
glands
Blastocyst
DAY 7
post fertilization
Blastocyst adheres
to uterine lining
Trophoblast
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Blastocoele
Inner cell
mass

26. Endometrial capillary
DAY 8 plasma membrane separates, trophoblast disappear creates cytoplasm
Endometrial capillary
Cellular
trophoblast
Syncytial trophoblast
Outer layer
hyaluronidase erodes uterine epithelium dissolves proteoglycans
DAY 9
Developing villi
Amniotic
cavity
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Lacuna
Figure 29-3 Stages in Implantation (Part 2 of 2).

27. Endometrial capillary
Figure 29-3 Stages in Implantation (Part 2 of 2).
Endometrial capillary
DAY 8
Syncytial trophoblast
Cellular
trophoblast
DAY 9
Amniotic
cavity
Developing villi
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Lacuna

28. Syncytial trophoblast Cellular trophoblast
Figure 29-4 The Inner Cell Mass and Gastrulation (Part 1 of 2).
Syncytial trophoblast
Cellular
trophoblast
Day 10: Yolk Sac Formation
Blastocoele
Amniotic
cavity
Superficial layer
Yolk sac
Deep layer
Lacunae
While cells from the superficial layer of the inner cell mass migrate around the amniotic cavity, forming the amnion, cells from the deeper layer migrate around the outer edges
of the blastocoele. This is the first step in the formation of the yolk sac, a second extraembryonic membrane. For about the next two weeks, the yolk sac is the primary nutrient source for the inner cell mass;it absorbs and distributes nutrients released into the blastocoele by the trophoblast.
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

29. Day 12, superficial cells of blastodisc
Figure 29-4 The Inner Cell Mass and Gastrulation (Part 2 of 2).
Day 12: Gastrulation
Yolk sac
Germ
Layers
Ectoderm
Amnion
Primitive streak
Endoderm
Mesoderm
Embryonic
disc
Blastodisc
Day 12, superficial cells of blastodisc
migrate toward a central line(primitive streak). At primitive streak, migrating cells leave surface, move between two existing layers. Creating 3 distinct embryonic layers: (1) the ectoderm, superficial cells that didn’t migrate
to interior blastodisc; (2) the endoderm, cells facing yolk sac; (3) the mesoderm, poorly organized layer of migrating cells between ectoderm and endoderm.
Gastrulation=migration produces an oval, three-layered sheet known as the embryonic disc. This disc will form the body of the embryo, whereas all other cells of the blastocyst will be part of the extra-
embryonic membranes Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

30. Germ layers form 4 Embryonic Membranes
Yolk sac-important blood cell formation site
Amnion-encloses fluid surrounding& cushioning developing embryo
Allantois-base gives rise to urinary bladder
Chorion-circulation w/in vessels provides rapid-transfer system linking embryo to trophoblast
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

31. Mesodermal migration around the endodermal pouch creates the yolk sac.
Figure 29-5 Extraembryonic Membranes and Placenta Formation (Part 3 of 7). 1
Week 2
Migration of mesoderm around the inner surface of the cellular trophoblast forms the chorion. Mesodermal migration
around the outside of the amniotic cavity, between the ectodermal cells and the trophoblast, forms the amnion.
Mesodermal migration around the endodermal pouch creates the yolk sac.
Chorion
Cellular trophoblast
Mesoderm
Amnion
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Blastocoele
Syncytial
trophoblast
Yolk sac

32. Syncytial trophoblast
Figure 29-5 Extraembryonic Membranes and Placenta Formation (Part 4 of 7). 2
Week 3
The embryonic disc bulges into the
amniotic cavity at the head fold. The
allantois, an endodermal extension
surrounded by mesoderm, extends
toward the trophoblast.
Extraembryonic
membranes
Amniotic cavity
(containing
amniotic fluid)
Amnion
Allantois
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Yolk sac
Head fold
of embryo
Chorion
Chorionic villi
of placenta
Syncytial trophoblast

33. trophoblast narrows the yolkstalk and body stalk.
Figure 29-5 Extraembryonic Membranes and Placenta Formation (Part 5 of 7). 3
Week 4
The embryo now has a head fold and a tail fold. Constriction of the connections between the embryo and the surrounding
trophoblast narrows the yolkstalk and body stalk.
Body stalk
Tail fold
Yolksac
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Yolk stalk
Embryonic
head fold
Embryonic gut

34. Figure 29-5 Extraembryonic Membranes and Placenta Formation (Part 6 of 7).4
Week 5
The developing embryo and extraembryonic membranes bulge into the uterine cavity. The trophoblast pushing out into the uterine cavity remains covered by endometrium but no longer participates in nutrient absorption and embryo support. The embryo moves away from the placenta, and the body stalk and yolk stalk fuse to form an umbilical stalk.
Umbilical
stalk
Decidua
basalis
Placenta
Yolk sac
Chorionic villi of
placenta
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Myometrium
Decidua
capsularis
Uterus
Decidua
parietalis
Uterine
cavity

35. The amnion has expanded greatly, filling the uterine cavity.
Figure 29-5 Extraembryonic Membranes and Placenta Formation (Part 7 of 7). 5
Week 10
The amnion has expanded greatly, filling the uterine cavity.
The fetus is connected to the placenta by an elongated
umbilical cord that contains a portion of the allantois,
blood vessels, and the remnants of the yolk stalk.
Decidua basalis
Umbilical cord
Placenta
Decidua parietalis
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Amnion
Amniotic cavity
Decidua capsularis
Chorion

36. Figure 29-6
Chorionic villi-extend outward into maternal tissue, forming branching network, maternal blood flows
Umbilical- connects fetus to placenta
Syncytial trophoblast- synthesize hCG, estrogen, progesterone, human placental lactogen(hPL), placental prolactin, relaxin
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

37. Umbilical Placenta cord (cut) Amnion Decidua capsularis Chorion
Figure 29-6a Views of Placental Structures (Part 1 of 3).
Umbilical
cord (cut)
Placenta
Amnion
Decidua
capsularis
Chorion
Yolk sac
Decidua
basalis
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
A view of the uterus after the fetus has been removed and the
umbilical cord cut. Arrows in the enlarged view indicate the
direction of blood flow. Blood flows into the placenta through
ruptured maternal arteries and then flows around chorionic
villi, which contain fetal blood vessels. a

38. Deciduaparietalis Myometrium Uterine cavity Cervical(mucous)
Figure 29-6a Views of Placental Structures (Part 2 of 3).
Deciduaparietalis
Myometrium
Uterine cavity
Cervical(mucous)
plug incervical canal
Cervix
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
External os
Vagina a
A view of the uterus after the fetus has been
removed and the umbilical cord cut. Arrows in
the enlarged view indicate the direction of blood
flow. Blood flows into the placenta through
ruptured maternal arteries and then flows around
chorionic villi, which contain fetal blood vessels.

39. Trophoblast (cellular
Figure 29-6a Views of Placental Structures (Part 3 of 3).
Chorionic
villi
Umbilical
vein
Umbilical
arteries
Area filled with
maternal blood
Amnion
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Maternal
blood vessels
Trophoblast (cellular
and syncytial layers) a
A view of the uterus after the fetus has been removed and
the umbilical cord cut. Arrows in the enlarged view indicate
the direction of blood flow. Blood flows into the placenta
through ruptured maternal arteries and then flows around
chorionic villi, which contain fetal blood vessels.

40. Embryonic Area filled with Syncytial connective tissue maternal blood
Figure 29-6b Views of Placental Structures.
Embryonic
connective tissue
Area filled with
maternal blood
Syncytial
trophoblast
Fetal blood
vessels
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Chorionic villus
LM × 280 b
A cross section through a chorionic
villus, showing the syncytial trophoblast
exposed to the maternal blood space.

41. The First 12 Weeks of Development. Vital for organogenesis
Future head of embryo
Thickened neural plate
(will form brain)
Axis of future
spinal cord
Somites
Neural folds
Cut wall of amniotic cavity
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Future tail of embryo a
Week 2. An SEM of the superior surface of a monkey
embryo at 2 weeks of development. A human embryo
at this stage would look essentially the same.

42. Figure 29-7b The First 12 Weeks of Development.
Medulla
oblongata
Ear
Pharyngeal
arches
Forebrain
Eye
Heart
Somites
Body stalk
Arm bud
Tail
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Leg bud b
Week 4. Fiber-optic view of human development
at week 4 (about 5 mm in size).

43. Figure 29-7c The First 12 Weeks of Development.
Chorionic
villi
Amnion
Umbilical
cord
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Placenta c
Week 8. Fiber-optic view of human
development at week 8 (about 1.6 cm in size).

44. Figure 29-7d The First 12 Weeks of Development.
Amnion
Umbilical
cord
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.). d
Week 12. Fiber-optic view of human development
at week 12 (about 5.4 cm in size).

45. Check Point
What is the developmental fate of the inner cell mass of blastocyst?
Improper development of which of the extraembryonic membranes would affect the cardiovascular system?
Sue’s pregnancy test indicates the presence of hCG. Explain whether she is pregnant or not.
What are two important functions of the placent?
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

46. You Tube https://www.youtube.com/watch?v=UgT5rUQ9EmQ
Review Video
You Tube

47. 29-5 During 2nd & 3rd trimester maternal organ systems support fetus & uterus undergoes structural & functional changes
Learning Outcomes
Describe interplay between maternal organ systems & developing fetus.
Discus structural & functional changes in the uterus during gestation.
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

48. 2nd Trimester organ systems increase in complexity
Figure 29-8a
2nd Trimester organ systems increase in complexity
3rd Trimester many organs fully functional,
Largest weight gain, fetus & enlarged uterus displace abdominal organs
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.). a
A four-month-old fetus, seen
through a fiber-optic endoscope
(about 13.3 cm in size)

49. Figure 29-8b The Second and
Third Trimesters- dependent on maternal organs for nourishment, respiration, waste removal. Maternal adaptations-increase respiratory rate, tidal volume, blood volume, nutrient/vitamin intake, GFR, changes in uterus & mammary glands
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Head of a six-month-
old fetus, revealed
through ultrasound
(about 30 cm in size) b

50. Figure 29-9a Growth of the Uterus and Fetus.
Placenta
Umbilical
cord
Uterus
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Amniotic fluid
Fetus at
16 weeks
Cervix
Vagina
Pregnancy at 16 weeks, showing the
positions of the uterus, fetus, and placenta. a

51. Figure 29-9b Growth of the Uterus and Fetus.
9 months
8 months
After dropping,
in preparation
to delivery
7 months
6 months
5 months
4 months
3 months
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.). b
Pregnancy at three months to nine months (full term), showing
the superior-most position of the uterus within the abdomen.

52. Figure 29-9c Growth of the Uterus and Fetus. Diaphragm Liver Stomach
Pancreas
Transverse colon
Small intestine
Uterus
Urinary bladder
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Pubic symphysis
Vagina
Urethra
Rectum c
A sectional view through the abdominopelvic
cavity of a woman who is not pregnant.

53. Figure 29-9d Growth of the Uterus and Fetus. Liver Fundus of uterus
Stomach
Pancreas
Transverse colon
Aorta
Small intestine
Common
iliac vein
Umbilical cord
Cervical (mucous)
plug in
cervical canal
Placenta
Uterus
Urinary bladder
Pubic symphysis
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
External os
Vagina
Urethra
Rectum d
Full term. Note the positions of the uterus and full-term fetus within the abdomen, and the displacement of abdominal organs.

54. Factors Involved in the Initiation of Labor and Delivery.
Placental Factors
Fetal Factors
Placental estrogens increase the sensitivity of the smooth
muscle cells of the myometrium and make contractions
more likely. As delivery approaches, the production of
estrogens accelerates. Estrogens also increase the
sensitivity of smooth muscle fibers to oxytocin.
Relaxin produced
by the placenta
relaxes the pelvic
articulations and
dilates the cervix.
Growth and the
increase in fetal
weight stretches
and distorts the
myometrium.
Fetal pituitary
releases
oxytocin in
response to
estrogens.
Distortion of Stretched Myometrium
Distortion of the myometrium increases
the sensitivity of the smooth muscle
layers, promoting spontaneous
contractions that get stronger and more
frequent as the pregnancy advances.
Labor contractions
move the fetus and
further distort the
myometrium. This
distortion stimulates
additional oxytocin
and prostaglandin
release. This
positive feedback
continues until
delivery is
completed.
Maternal Oxytocin Release
Prostaglandin Production
Maternal oxytocin release is
stimulated by high estrogen levels
and by distortion of the cervix.
Estrogens and oxytocin stimulate the production of
prostaglandins in the endometrium. These prostaglandins
further stimulate smooth muscle contractions.
Figure read and discus Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
Increased Excitability of the Myometrium
Oxytocin and prostaglandins both stimulate the myometrium. In addition, the sensitivity of the uterus to oxytocin
increases dramatically. The smooth muscle in a late-term uterus is 100 times more sensitive to oxytocin than the
smooth muscle in a nonpregnant uterus.
LABOR CONTRACTIONS OCCUR

55. Check Point Why do woman experience breathing difficulty?
Identify 3 major factors opposing calming action of progesterone on the uterus.
Why do mother blood volume increase during pregnancy?
Differentiate between true and false labor.
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).

56. Review Video Second trimester.
Third trimester. M

57. References
Martini, Nath & Bartholomew (2105), Fundamentals of Anatomy and Physiology (10th ed.).
You Tube