by Patty Bostwick-Taylor, Florence-Darlington Technical ...
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PowerPoint® Lecture Slide Presentation
by Patty Bostwick-Taylor,
Florence-Darlington Technical College
Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings
PART B16
The
Reproductive
System
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Female Reproductive System
Ovaries
Duct System
Uterine tubes (fallopian tubes)
Uterus
Vagina
External genitalia
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Female Reproductive System
Figure 16.8a
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Ovaries
Composed of ovarian follicles (sac-like
structures)
Each follicle consists of
Oocyte (immature egg)
Follicular cells—surround the oocyte
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Ovaries
Figure 16.7
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Ovarian Follicle Stages
Primary follicle—contains an immature oocyte
Graafian (vesicular) follicle—growing follicle with a maturing oocyte
Ovulation—when the egg is mature, the follicle ruptures; occurs about every 28 days
The ruptured follicle is transformed into a corpus luteum
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Support for Ovaries
Suspensory ligaments—secure ovary to lateral
walls of the pelvis
Ovarian ligaments—attach to uterus
Broad ligament—a fold of the peritoneum,
encloses suspensory ligament
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Female Reproductive System
Figure 16.8b
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Duct System
Uterine tubes (fallopian tubes)
Uterus
Vagina
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Uterine (Fallopian) Tubes
Receive the ovulated oocyte
Provide a site for fertilization
Attach to the uterus
Little or no contact between ovaries and uterine
tubes
Supported and enclosed by the broad ligament
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Uterine Tube Anatomy and Physiology
Fimbriae
Finger-like projections at the distal end of the
uterine tube
Receive the oocyte from the ovary
Cilia
Located inside the uterine tube
Slowly move the oocyte towards the uterus
(takes 3–4 days)
Fertilization occurs inside the uterine tube since
oocyte lives about 24 hours
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Female Reproductive System
Figure 16.8b
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Uterus
Located between the urinary bladder and rectum
Hollow organ
Functions of the uterus
Receives a fertilized egg
Retains the fertilized egg
Nourishes the fertilized egg
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Support for the Uterus
Broad ligament—attached to the pelvis
Round ligament—anchored anteriorly
Uterosacral ligaments—anchored posteriorly
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Female Reproductive System
Figure 16.8b
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Regions of the Uterus
Body—main portion
Fundus—superior rounded region above where
uterine tube enters
Cervix—narrow outlet that protrudes into the
vagina
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Walls of the Uterus
Endometrium
Inner layer
Allows for implantation of a fertilized egg
Sloughs off if no pregnancy occurs (menses)
Myometrium—middle layer of smooth muscle
Perimetrium (visceral peritoneum)—outermost
serous layer of the uterus
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Female Reproductive System
Figure 16.8b
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Vagina
Extends from cervix to exterior of body
Located between bladder and rectum
Serves as the birth canal
Receives the penis during sexual intercourse
Hymen—partially closes the vagina until it is
ruptured
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Female Reproductive System
Figure 16.8b
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External Genitalia (Vulva)
Mons pubis
Labia
Clitoris
Urethral orifice
Vaginal orifice
Greater vestibular glands
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Figure 16.9
External Genitalia (Vulva)
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Mons Pubis
Fatty area overlying the pubic symphysis
Covered with pubic hair after puberty
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Mons Pubis
Figure 16.9
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Labia
Labia—skin folds
Labia majora—hair-covered skin folds
Labia minora—delicate, hair-free folds of skin
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Labia
Figure 16.9
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Vestibule and Greater Vestibular Glands
Vestibule
Enclosed by labia majora
Contains external openings of the urethra,
vagina
Greater vestibular glands
One is found on each side of the vagina
Secretes lubricant during intercourse
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Vestibule and Orifice of Vestibular Gland
Figure 16.9
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Clitoris
Contains erectile tissue
Corresponds to the male penis
The clitoris is similar to the penis in that it is
Hooded by a prepuce
Composed of sensitive erectile tissue
Becomes swollen with blood during sexual
excitement
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Clitoris
Figure 16.9
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Perineum
Diamond-shaped region between the anterior
ends of the labial folds, anus posteriorly, and
ischial tuberosities laterally
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Perineum
Figure 16.9
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Oogenesis and the Ovarian Cycle
The total supply of eggs are present at birth
Ability to release eggs begins at puberty
Reproductive ability ends at menopause
Oocytes are matured in developing ovarian
follicles
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Oogenesis and the Ovarian Cycle
Oogonia—female stem cells found in a developing
fetus
Oogonia undergo mitosis to produce primary
oocytes
Primary oocytes are surrounded by cells that
form primary follicles in the ovary
Oogonia no longer exist by the time of birth
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Oogenesis and the Ovarian Cycle
Primary oocytes are inactive until puberty
Follicle stimulating hormone (FSH) causes some
primary follicles to mature each month
Cyclic monthly changes constitute the ovarian
cycle
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Oogenesis and the Ovarian Cycle
Meiosis starts inside maturing follicle
Produces a secondary oocyte and the first polar
body
Follicle development to the stage of a vesicular
follicle takes about 14 days
Ovulation of a secondary oocyte occurs with the
release of luteinizing hormone (LH)
Secondary oocyte is released and surrounded by
a corona radiata
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Ovulation (VIDEO)
Figure 16.11
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Oogenesis and the Ovarian Cycle
Meiosis is completed after ovulation only if sperm
penetrates
Ovum is produced
Two additional polar bodies are produced
Once ovum is formed, the 23 chromosomes can
be combined with those of the sperm to form the
fertilized egg (zygote)
If the secondary oocyte is not penetrated by a
sperm, it dies and does not complete meiosis to
form an ovum
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Male and Female Differences
Meiosis
Males—produces four functional sperm
Females—produces one functional ovum and
three polar bodies
Sex cell size and structure
Sperm are tiny, motile, and equipped with
nutrients in seminal fluid
Egg is large, non-motile, and has nutrient
reserves to nourish the embryo until
implantation
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Oogenesis
Figure 16.10
Meiotic Events Follicle Development
in OvaryBefore birth
Childhood
Primary oocyte
Primary oocyte (still
arrested in prophase I)
Mature
vesicular
(Graafian)
follicle
Primary
follicle
Primary
follicle
Primary
follicle
Oocyte
Ovulated
secondary
oocyte
Growing
follicle
Primary oocyte
(arrested in prophase I;
present at birth)
Oogonium (stem cell)
Each month from
puberty to menopause
Meiosis I (completed by one
primary oocyte each month)
First polar body
Mitosis
Growth
Meiosis II of polar body
(may or may not occur)
Polar bodies
(all polar bodies
degenerate)
OvumSecond
polar body
Meiosis II completed
(only if sperm
penetration occurs)
Sperm
Ovulation
Secondary oocyte
(arrested in
metaphase II)
Follicle cells
(ovary inactive)
2n
2n
2n
2n
n
nnn n
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Oogenesis
Figure 16.10, step 1
Meiotic Events Follicle Development
in OvaryBefore birth
Primary oocytePrimary
follicle
Oocyte
Oogonium (stem cell)
MitosisFollicle cells
2n
2n
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Oogenesis
Figure 16.10, step 2
Meiotic Events Follicle Development
in OvaryBefore birth
Primary oocyte
Primary
follicle
Primary
follicle
Oocyte
Primary oocyte
(arrested in prophase I;
present at birth)
Oogonium (stem cell)
Mitosis
Growth
Follicle cells
2n
2n
2n
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Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings
Oogenesis
Figure 16.10, step 3
Meiotic Events Follicle Development
in OvaryBefore birth
Childhood
Primary oocyte
Primary
follicle
Primary
follicle
Oocyte
Primary oocyte
(arrested in prophase I;
present at birth)
Oogonium (stem cell)
Mitosis
Growth
Follicle cells
(ovary inactive)
2n
2n
2n
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Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings
Oogenesis
Figure 16.10, step 4
Meiotic Events Follicle Development
in OvaryBefore birth
Childhood
Primary oocyte
Primary oocyte (still
arrested in prophase I)
Primary
follicle
Primary
follicle
Primary
follicle
Oocyte
Growing
follicle
Primary oocyte
(arrested in prophase I;
present at birth)
Oogonium (stem cell)
Each month from
puberty to menopause
Mitosis
Growth
Follicle cells
(ovary inactive)
2n
2n
2n
2n
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Oogenesis
Figure 16.10, step 5
Primary oocyte (still
arrested in prophase I)
Mature
vesicular
(Graafian)
follicle
Primary
follicle
Growing
follicle
Each month from
puberty to menopause
2n
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Oogenesis
Figure 16.10, step 6
Primary oocyte (still
arrested in prophase I)
Mature
vesicular
(Graafian)
follicle
Primary
follicle
Ovulated
secondary
oocyte
Growing
follicle
Each month from
puberty to menopause
Meiosis I (completed by one
primary oocyte each month)
First polar body
Ovulation
Secondary oocyte
(arrested in
metaphase II)
2n
n
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Oogenesis
Figure 16.10, step 7
Primary oocyte (still
arrested in prophase I)
Mature
vesicular
(Graafian)
follicle
Primary
follicle
Ovulated
secondary
oocyte
Growing
follicle
Each month from
puberty to menopause
Meiosis I (completed by one
primary oocyte each month)
First polar body
Sperm
Ovulation
Secondary oocyte
(arrested in
metaphase II)
2n
n
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Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings
Oogenesis
Figure 16.10, step 8
Primary oocyte (still
arrested in prophase I)
Mature
vesicular
(Graafian)
follicle
Primary
follicle
Ovulated
secondary
oocyte
Growing
follicle
Each month from
puberty to menopause
Meiosis I (completed by one
primary oocyte each month)
First polar body
Meiosis II of polar body
(may or may not occur)
Polar bodies
(all polar bodies
degenerate)
OvumSecond
polar body
Meiosis II completed
(only if sperm
penetration occurs)
Sperm
Ovulation
Secondary oocyte
(arrested in
metaphase II)
2n
n
nnn n
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Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings
Oogenesis
Figure 16.10, step 9
Meiotic Events Follicle Development
in OvaryBefore birth
Childhood
Primary oocyte
Primary oocyte (still
arrested in prophase I)
Mature
vesicular
(Graafian)
follicle
Primary
follicle
Primary
follicle
Primary
follicle
Oocyte
Ovulated
secondary
oocyte
Growing
follicle
Primary oocyte
(arrested in prophase I;
present at birth)
Oogonium (stem cell)
Each month from
puberty to menopause
Meiosis I (completed by one
primary oocyte each month)
First polar body
Mitosis
Growth
Meiosis II of polar body
(may or may not occur)
Polar bodies
(all polar bodies
degenerate)
OvumSecond
polar body
Meiosis II completed
(only if sperm
penetration occurs)
Sperm
Ovulation
Secondary oocyte
(arrested in
metaphase II)
Follicle cells
(ovary inactive)
2n
2n
2n
2n
n
nnn n