E learning repro sys

Just read it. Okay?

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The The
ReproductiveReproductive
SystemsSystems

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Main function: propagation of the species
To achieve this goal: must ensure
1. Sexual maturation
2.Produce gametes (n).
Male and female structures are
homologues:
derived from common developmental
tissues
The Reproductive SystemsThe Reproductive Systems

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Male Reproductive SystemMale Reproductive System
•Organs: testes, ducts, glands &
supporting structures
•Ducts: epididymis, ductus deferens,
ejaculatory ducts & urethra
•Glands: seminal vesicles, prostate,
bulbourethral glands
•Supporting structures include
scrotum & penis

5. Figure 23.1Figure 23.1

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ScrotumScrotum
•Pouch that supports the testes
•Septum separates into separate
sections for each testis
•Sperm requires temperatures 2-3
o
C
below body temperature
•allows raising and lowering testes to
adjust temperature

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TestesTestes
•Paired oval glands
•Develop on embryo’s posterior wall
and descend into scrotum
Starts in 7
th
month
•Where spermatogenesis
(formation & production of sperm
cells) occur

8. Figure 23.2bFigure 23.2b

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Spermatozoa StructureSpermatozoa Structure
•~300 million /day
Life time ~ 48 hrs in female tract
•Structure: Head, middle, tail
•tail- flagellum = motility
•Middle - mitochondria = energy
•Head-chromosomes + acrosomal cap
•acrosome-enzymes-> penetrating egg

10. Figure 23.4Figure 23.4

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•Female typically produces and
releases a single oocyte monthly.
•Male produces 100,000,000 of
(sperm) daily.
male gametes are stored for a short
time
if they are not expelled from the body
within that period, they are resorbed

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Androgen EffectsAndrogen Effects
•Prenatal- male pattern of development:
Male ducts, descent of testes, external genitals
& brain regions
•Puberty: enlargement of organs, secondary
characteristics:
Muscular & skeletal growth, hair patterns,
thickening of skin
•Sexual function: sexual behavior,
spermatogenesis & libido
•Stimulation of anabolism: stimulate protein
synthesis & muscle & bone growth

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Accessory GlandsAccessory Glands
•Seminal vesicles- seminal fluid-
Fructose -sperm ATP production
+ alkalinity (neutralize acid in tracts)
+ prostaglandins-activation of sperm
•Prostate- surrounds upper urethra
Increases volume + adds antibiotics
•Bulbourethral glands:
More alkalinity + mucus fluid

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PenisPenis
•Contains urethra- root, body & glans penis
Passage for semen & urine
•Root- attached portion
•Body- 3 cylindrical masses erectile
Dorsal – Corpora Cavernosa Penis
Midventral- Corpus Spongiosum penis- contains
urethra
•Glans penis has external urethral oriface
•Uncircumcised glans covered by prepuce

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Female Reproductive SystemFemale Reproductive System
•Ovaries: paired organs- produce
secondary oocytes ova (after
fertilization)
Hormones: progesterone & estrogens
From same embryonic tissue as testes
•uterine (fallopian) tubes & uterus
•cervix & vagina
•External organs (collectively called
vulva or pudendum)

16. Figure 23.6

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OogenesisOogenesis
•Production or formation of egg cells
•Begins before birth-
Oocytes not continually produced
•Meiosis I- start before birth

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Uterine TubesUterine Tubes
•Two tubes- extend laterally from
uterus
•End in fringe  Fimbriae
•Fimbriae sweep secondary oocyte
into tube
•Oocyte moved by cilia lining wall
•Zygote reaches uterus in ~7 days

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UterusUterus
•Parts:
•Fundus -Dome-shaped area above
tubes=
•Body – tapering central portion
•Cervix- narrow opening into vagina
•Uterine cavity- interior of body

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The Uterus Serves Four The Uterus Serves Four
FunctionsFunctions
•Site for implantation.
pre-embryo implants into the inner uterine wall and becomes
connected to the uterine lining
•Supports, protects, and nourishes the developing embryo/fetus
forms a vascular connection with the mother’s uterine wall that
later develops into the placenta
•Ejects the fetus at birth after maternal oxytocin levels increase
to initiate the uterine contractions of labor.
•Site for menstruation.
if an oocyte is not fertilized or after a baby is expelled, the
muscular wall of the uterus contracts and sheds its inner
lining as menstruation

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VaginaVagina
•extends from exterior to cervix
•Fornix- recess surrounds cervix
•Acid environment- prevents bacterial
growth
•Smooth muscular layer- adjusts for
intercourse or birth
•Thin membrane fold can cover vaginal
orifice = hymen

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•The vagina is
thick-walled, fibromuscular tube
forms the inferior-most region of the female reproductive tract
measures about 10 centimeters in length in an adult female.
•The vagina connects the uterus with the outside of the body
anteroventrally
functions as the birth canal.
•Also the copulatory organ of the female
•Serves as the passageway for menstruation and the baby when
• giving birth (PARTURITION) in a normal delivery
•The vaginal wall is heavily invested with both blood vessels and
lymphatic vessels.
•The vagina’s relatively thin, distensible wall consists of three
tunics:
an inner mucosa, a middle muscularis, and an outer adventitia

23. Figure 23.9Figure 23.9

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Perineum & vulvaPerineum & vulva
•Perineum: Diamond-shaped area
between thigh & buttocks of both males &
females
•Vulva or pudendum = external genitalia
•Mons pubis- elevation of adipose tissue
•labia majora- extends back from mons
pubis
Same fetal tissue as scrotum
•Labia minora- internal to majora

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Perineum & vulva (cont.)Perineum & vulva (cont.)
•Clitoris- small cylindrical mass of erectile
tissue & nerves
Also contains prepuce & glans
•Vestibule: between labia minora
•External urethral orifice- anterior to
vaginal orifice
•Paraurethral glands- either side of urethra
Same embryonic tissue as prostate
Secretes mucus
•Greater vestibular glands- adds to mucus
Comparable to bulbourethral glands

26. Figure 23.10Figure 23.10

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Mammary GlandsMammary Glands
•Modified sudoriferous glands
•Nipple- pigmented projection with
openings
•Areola- surrounds nipple
•Internally-15-20 lobes lobules alveoli
= milk secreting glands
Matures at puberty
•Lactation = synthesis, secretion &
ejection of milk

28. Figure 23.11Figure 23.11

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HormonesHormones
•Estrogen:
Development & maintenance of reproductive
structures & secondary characteristics
 protein synthesis & growth
Lower blood cholesterol level
•Progesterone maintains myometrium for
implantation
•Relaxin= relaxes uterus- inhibits
myometrium
•Inhibin- inhibits FSH release

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When a woman has stopped having monthly menstrual
cycles for 1 year and is not pregnant, she is said to be in
menopause.
The age at onset typically is between 45 and 55 years
follicles stop maturing, and significant amounts of estrogen and
progesterone are no longer being secreted
a woman’s endometrial lining does not grow, and she no longer has a
menstrual period

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Comparison of the Female and Comparison of the Female and
Male Reproductive Systems Male Reproductive Systems
•Primary sex organs called gonads.
ovaries in females
testes in males
•Produce gametes which unite to form a new individual.
Egg cell / ovum
sperm
•Gonads produce large amounts of sex hormones which affect
maturation, development, and changes in the activity of the
reproductive system organs.
estrogen and progesterone in the female
androgens (esp. testosterone) in the male

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•Both have accessory reproductive organs
duct systems
•carry gametes away from the gonads
•toward the site of fertilization in females
•to the outside of the body in males
•Fertilization occurs when male and female
gametes meet:
copulation, coitus, sexual intercourse
Restores the diploid number (2n)

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Birth Control MethodsBirth Control Methods
•ARTIFICIAL
1. Surgery – cut or tie
vasectomy in males - ductus deferens
tubal ligation in female - uterine tubes
2. Chemical interference
oral hormones, implants, injections, spermicide
3. Blocking physically
IUD, condoms, diaphragm, cervical cap

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•NATURAL

body temperature
cervical mucus
calendar / rhythym
coitus interruptus / withdrawal
abstinence

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2 Ways to having twins2 Ways to having twins
IDENTICAL TWIN results from 1 ovum
fertilized by 1 sperm cell that splits into
2 during fetal development
FRATERNAL TWIN results from 2 ova
fertilized by 2 sperm cells separately

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AgingAging
•Puberty- pulses of LH & FSH
•Rise in sex steroids
Growth & secondary characteristics
start of female reproductive cycle
•follicles become exhausted Menopause
estrogen secretion declines
lose feedback on pituitary  high FSH & LH
Decline in estrogen supported functions
•In males- slower decline of function

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•Thereafter, changes occur in many body structures, the
reproductive organs mature, and gonads begin to produce
gametes.
•Gametes stop maturing in females in their 40s or 50s, and
menopause occurs.
•A reduction in hormone production that accompanies
menopause causes some atrophy of the reproductive organs
and the breasts.
•The vaginal wall thickness decreases, as do glandular
secretions for maintaining a lubricated and moist lining.
•The uterus shrinks and atrophies, becoming much smaller than
it was before puberty.