BMSC208 - Reproduction Flashcards
(277 cards)
1
Q
Why is human reproduction considered advanced than other animals?
A
mate for pleasure and procreation, mating does not only occur during fertile periods
2
Q
Sexual dimorphism of humans
A
males and females have distinct physical characteristics
3
Q
3 structures that male and female sex organs consist of
A
gonads, internal genitalia, external genitalia
4
Q
Gonads ( _ -producing organs)
A
gamete-producing organs
5
Q
Internal genitalia ( _ glands and _ )
A
accessory glands and ducts
6
Q
External genitalia ( _ _ structures)
A
external reproductive structures
7
Q
Sex determination is programmed in the…
A
genome
8
Q
Chromosomes in each nucleated cell of body
A
23 pairs (diploid) - 22 pairs of autosomes (direct human body development), 1 pair of sex chromosomes (direct development of internal and external sex organs)
9
Q
Chromosome numbers in gametes
A
23 single chromosomes (haploid)
10
Q
X-chromosome inactivation
A
in females, during early embryonic development, one X chromosome is turned off in each cell - whether the paternal or maternal is shut off differs in each cell (calico cat)
11
Q
Common X-linked recessive genetic disorders
A
muscular dystrophy, colour blindness, hemophilia
12
Q
Result of nondisjunction during M1( _ disomic gametes, _ nullisomic gametes)
A
2 disomic gametes, 2 nullisomic gametes
13
Q
Result of nondisjunction during M2 ( _ disomic gamete, _ nullisomic gamete, _ normal monosomic gametes)
A
1 disomic gamete, 1 nullisomic gamete, 2 normal monosomic gametes
14
Q
XXY sex chromosome distribution ( _ syndrome)
A
Klinefelter’s syndrome, caused by nondisjunction at M1 or M2, genetically male
15
Q
Klinefelter’s syndrome symptoms
A
tall, slightly feminized physique, mildly impaired IQ, infertile
16
Q
X sex chromosome distribution ( _ syndrome)
A
Turner’s syndrome, nullisomic gamete is fertilized, genetically female
17
Q
Turner’s syndrome symptoms
A
short, neck webbing, broad chest, infertility
18
Q
Y sex chromosome distribution (is it possible?)
A
not possible, need X chromosome to be viable
19
Q
XXX and XYY sex chromosome distribution
A
are often undetected, have increased chance of lower IQ, thought to be increased aggression as few serial killers are but was disproved
20
Q
Embryo period
A
fertilization - end of 8th week
21
Q
Steps of embryo period
A
egg, zygote, 2-cell stage, 4-cell stage, morula, blastocyst
22
Q
Fetus period ( _ week to _)
A
start of 9th week to birth
23
Q
Bipotential (structures do not _ until the _ week)
A
reproductive structures do not start to differentiate until the 7th week of development and are considered bipotential until this point
24
Q
2 gonads
A
outer cortex, inner medulla
25
**Gonad** development in **females** ( _ cortex forms _, inner _ regresses )
**outer cortex** forms **ovary, inner medulla** regresses
26
**Gonad** development in **males** ( _ cortex regresses, _ medulla forms the _ that creates the AMH)
**outer cortex** regresses, **inner medulla forms the testis** that creates the AMH
27
2 accessory ducts
Wolffian duct, Mullerian duct
28
Accessory duct development in **females** (in abscence of _ the _ _ forms the fallopian tube, uterus, cervix, and upper half of vagina, the _ _ regresses)
in **absence of AMH** the **Mullerian duct** forms the fallopian tube, uterus, cervix, and upper half of vagina, the Wolffian duct regresses
29
Accessory duct development in **males** (in presence of _ the _ _ regresses, _ _ forms the _, _ _, and _ _)
in **presence of AMH** the Mullerian duct regresses, the **Wolffian duct** **forms** the **epididymis, vas deferens, and seminal vesicle**
30
Male/Female development depends on...
the presence or absence of the SRY gene
31
SRY gene
the sex determining region of the Y chromosome
32
SRY gene produces...
testis determining factor (TDF)
33
**TDF** produces _, _, _ that guide development of **gonad medulla into testis**
**SOX9, WT1, SF1** that guide the development of the gonad medulla into testis
34
3 hormones produced by testis
**Anti-Mullerian hormone** (sertoli cells), **testosterone** (leydig cells), **dihydrotestosterone** (leydig cells)
35
Anti-Mullerian hormone (causes _ _ to regress)
causes mullerian ducts to regress
36
Testosterone (converts _ _ into male accessory structures)
converts **Wolffian ducts** into **male** accessory structures **(epididymis, vas deferens, seminal vesicles)**
37
Dihydrotestosterone determines differentiation of _ _
differentiation of external genitalia
38
Role of **SRY** and **SOX9** (suppress female _ by inhibiting _ )
suppress **female pathways** by inhibiting **FOXL2**
39
Internal **female** genitalia differentiation at **10 weeks** ( _ cortex becomes _ in absence of _ protein, absence of _ causes the _ _ to degenerate)
**gonadal cortex becomes ovary** in **absence of SRY protein** and in presence of female-specific genes, the **absence of *testosterone* causes the Wolffian duct to degenerate**
40
Internal **female** genitalia differentiation at **birth** (absence of _ allows _ _ to become fallopian tube, uterus, and upper vagina)
**absence of AMH allows Mullerian duct to become fallopian tube,** uterus, and upper vagina
41
Internal **male** genitalia differentiation at **10 weeks** ( _ protein directs medulla of bipotential gonad to develop into _, _ from testis causes _ _ to disappear)
**SRY protein directs medulla of bipotential gonad to develop into testis**, **AMH** from testis **causes Mullerian ducts to disappear**
42
Internal **male** genitalia differentiation at **birth** ( _ from testis converts _ _ into _ _, _ _, and _. _ controls prostate development)
**testosterone** from testis converts **Wolffian duct** into **seminal vesicle, vas deferens**, and **epididymis.** **DHT** controls prostate development
43
3 structures in external genitalia development
genital tubercle, urethral groove/urethral fold, labioscrotal swelling
44
External genitalia development driven by...
presence or absence of androgens (**dihydrotestosterone**)
45
Genital tubercle in female development (forms _ )
forms clitorus
46
Urethral folds and grooves in female development (forms _ _, opening of _ and _ )
forms **labia minora**, opening of **vagina** and **urethra**
47
**Labioscrotal swellings** in female development forms _ _
forms **labia majora**
48
Genital tubercle in male development forms _ _
forms glans penis
49
Urethral folds and grooves in male development forms _ of _
forms shaft of penis
50
Labioscrotal swellings in male development (forms _ of _ and _ )
forms shaft of penis and scrotum
51
**External female** genitalia differentiation at **10 weeks** (in abscence of _, the _ genitalia are feminizied)
in **absence of dihydrotestosterone (DHT),** the **external genitalia** are feminized
52
**External male** genitalia differentiation at **10 weeks** (presence of _ causes development of male _ genitalia)
**presence of dihydrotestosterone (DHT)** causes the development of male **external genitalia**
53
**External male** genitalia differentiation at **birth** ( _ descend from abdominal cavity into the _ )
the **testes** descend from the abdominal cavity into the **scrotum**
54
Male pseudohermaphrodites (have defective _ gene (convert _ to _), lack of _ results in failure of male external genital and prostate development)
have **defective 5a-reductase gene** (convert **testosterone** to **DHT**), lack of **DHT** results in failure of **male external genital** and **prostate** development
55
Male pseudohermaphrodites at puberty (testes begin to secrete _ again to cause masculininzation of _ genitalia)
testes begin to secrete **testosterone** again to cause masculinization of **external** genitalia
56
Testis and ovaries produce _ and _
hormones and gametes
57
Egg characteristics
largest cells in body, **non-motile** (**move via smooth muscle contraction or cilia**), are born with all oocytes you will have that are cyclically released during reproductive years (about 40 years)
58
Sperm characteristics
small, only flagellated cells in body (motile), are continuously produced after reaching reproductive maturity, production diminishes with age but does not cease
59
Gametogenesis means production of _
production of gametes
60
Mitosis in gametogenesis (begins in-_ to increase _ cell numbers)
begins in **utero** to increase **germ** cell numbers
61
**General gametogenesis** (germ cell division) steps
germ cells in embryonic gonads undergo **mitotic divisions to increase number, duplication of chromosomes *(92),*** ***one primary gamete divides into 2 secondary gametes*** (each have *46*), ***secondary gametes divide to produce haploid gametes*** (*23* chromosomes = 23 chromatids)
62
Oogonia are
female germ cells
63
Female gametogenesis steps
**mitosis and first stage of meiosis occur by 5th month of fetal development,** at birth are 500,000 primary oocytes, **meiosis resumes at puberty,** **first division produce large secondary oocyte and small polar body,** **the egg begins second meiotic division and polar bodies break down,** the **ovary releases egg and it does not undergo secondary division unless fertilized,** **if fertilized will undergo division to shed polar body with 23 chromosomes, are 23 chromosomes in ovum and 23 new from sperm**
64
**Secondary oocyte** contains #_ chromosomes, only undergoes _ _ if fertilized)
contains **46** chromosomes, only undergoes **second division** if fertilized
65
Why don't polar bodies survive?
uneven division causes polar bodies to be very small with very little cytoplasm and a few organelles
66
Male and female gametogenesis is under control of _ from brain and _ cells in the gonads
**hormones** from brain and **endocrine** cells in the gonads
67
Steps of male gametogenesis
at **birth testis contain immature germ cells and remain quiescent,** at puberty **germ cell mitosis resumes producing** germ cells (**spermatogonia**), some **spermatogonia continue in mitosis** and **some enter meiosis to produce primary spermatocytes, secondary spermatocytes, spermatids,** and then **sperm**
68
Reproduction begins with secretion of peptide hormones ( _ ) from _ that act on **anterior pituitary** to cause release of _ and _, they then go to _ and cause secretion of sex hormones ( _, _, _ )
**secretion** of **peptide** hormones (**GnRH**) from **hypothalamus** that act on anterior pituitary to cause **release of LH and FSH,** they then **go to gonads** and cause **secretion of sex hormones (androgens, estrogens, progesterone)**
69
All sex hormones are derived from...
cholesterol
70
Androgen production in males by what
95% testes, 5% adrenal gland, most is converted to DHT in periphery
71
Female sex hormone production (produce primarily _ and _ in ovaries)
produce primarily **estrogens** and **progesterone** in ovaries
72
Hypothalamic-pituitary-gonadal axis ( _ produced in hypothalamic neurons controls secretion of _ and _ from gonadotropes that act on _ )
gonadotropin releasing hormone (**GnRH**) produced in hypothalamic neurons **controls secretion of** 2 anterior pituitary gonadotropins **from gonadotropes** (**FSH and LH**) that **act on gonads**
73
**Hypophyseal** portal system (how the _ communicates with the _ pituitary)
how the **hypothalamus** communicates with the **anterior** pituitary
74
Hypophyseal portal system steps
neurons synthesizing trophic neurohormones release them into capillaries of the portal system, portal veins then carry the trophic neurohormones directly to the anterior pituitary where they act on the endocrine cells, endocrine cells release their peptide hormones into the second set of capillaries for distribution to the rest of the body
75
**Short-term negative feedback** ( _ and _ inhibits _ release from **hypothalamus** when their concentrations are too high
**LH and FSH inhibits GnRH** **release** from hypothalamus **when their concentrations are too high**
76
**Estrogen feedback** (is _ to a point but with sustained higher concentrations will become a _ feeback to drive _ and _ higher)
is **negative to a point,** but with sustained higher concentrations will become a **positive** feeback to **drive GnRH and LH higher** to play a significant role in the female reproductive cycle
77
**Inhibin** role (inhibit _ secretion, which increases _ levels)
when estrogen is in positive feedback loop, **inhibins** are also released which **inhibit FSH secretion, which increases LH levels**
78
Effect of low estrogen or androgen
absense of negative feedback, GnHR increases
79
Effect of **moderate** estrogen or androgen
negative feedback causes **decreased GnHR**
80
Effect of **high** androgen
negative feedback causes **decreased GnHR**
81
Effect of high estrogen
**positive** feedback causes **increased GnHR**
82
Feedback at anterior pathways is on...
gonatropes
83
Feedback at **hypothalamus** is directly on _ neurons or via _ -containing neurons
directly on **GnRH** neurons or via **kisspeptin**-containing neurons
84
GnRH release from _ in _ fashion
from **hypothalamus in pulsatile** fashion every **1-3 hours** in males and females
85
Children with GnRH deficiency will not mature sexually without _ stimulation of hormones, will deliver eynthetic _ in pulsative manner
will not mature sexually without **gonadtrophin stimulation** of hormones, will deliver **synthetic GnRH** in pulsative manner
86
Result of constant GnRH delivery (downregulation of _ in the pituitary _ )
downregulation of receptors in the pituitary gonadotropes
87
High GnRH treatment
certain breast or prostate cancers that are driven by sex hormones, by stopping their productions will slow tumour growth
88
Pulsatile activity in kisspeptin neurons stimulates...
GnRH neurons to release GnRH
89
GnRH binds _ receptor on _ in anterior pituitary to stimulate _ and _ release
**GnRH** receptor on **gonadotropes** in anterior pituitary to stimulate **LH** and **FSH** release
90
LH and FSH act on...
gonads to stimulate hormone secretion and facilitate gamete production
91
Reproductive cycle in women is easier to study because...
physiological uterine bleeding during menstrual cycle can be monitored
92
Environmental factors on reproduction
nutritional status, physical activity, change of day/light cycles
93
Role of environmental estrogen
can bind and activate estrogen receptors
94
Anti-estrogens
interfere with second messenger pathways, may influence developing embryo/fetus
95
Testes role
produce hormones and gametes
96
Urethra (passage for _ and _ to leave body)
passage for **semen** and **urine** to leave the body
97
Corpus spongiosum
tissue surrounding urethra to keep it open during erection
98
Corpora cavernosa
tissue that blood flows through to make erection
99
Possible benefits to circumcision
hygiene, decreased cancer, STI, UTI, HIV
100
3 male internal genitalia
accessory glands, vas deferens, epididymis
101
3 accessory glands
seminal vesicle, prostate gland, bulbourethral gland
102
2 external male genitalia
penis, scrotum
103
Scrotum
external sac that testes migrate into, to keep testis lower temperature
104
Temperature for sperm development
2-3 F or lower
105
Cryptorchidism
failure for testes to migrate into scrotum, usually will resolve self in one year
106
Cryptorchidism symptoms
unable to produce sperm, still produce androgens
107
Cryptorchidism treatment
move testes to scrotum with **testosterone treatment or surgically**
108
Vas deferens connect _ to _
connect **epididymis** to **urethra** (empty secretions into it)
109
epididymis
storage reservoir for sperm
110
Benign prostatic hypertrophy
growth of prostate, common in men over 50, causes increased pressure on urethra and bladder
111
Benign prostatic hypertrophy treatment
**5a-reductase** (convert testestorone to DHT) **inhibitor** to **block DHT production,** causes enlarged prostate to shrink
112
2 uses of finasteride
**benign prostatic hypertrophy** (enlarged prostate), **androgenic alopecia** (male pattern baldness **from increased DHT**)
113
Testis structure
2 ovoid structures about 2.5x5 cm, are tough fibrous capsules split into 250-300 compartments
114
Seminiferous tubule structure
400-600 tubes in testis compartments (80% testis mass), are 0.3-1m long
115
Between seminiferous tubules in compartments
interstitial tissue with blood vessels and Leydig cells
116
Epididymis in testes
where sperm matures and is stored until ejaculation
117
Seminiferous tubule role (site of _ production)
**site of sperm production** - developing spermatocytes stack in columns from outer edge to lumen with sertoli cells between each column
118
Leydig cell location and role
in **interstitial tissue in testes,** **produce testosterone** during development and after puberty
119
Basal lamina of seminiferous tubule
keep out large particles, allow testosterone to enter
120
Myoid cells
smooth muscle cells in seminiferous tubules that push cells forward to lumen
121
Sertoli cell tight junctions
form with adjacent sertoli cells to **form a blood-testis barrier between tubule lumen and interstitial space**
122
Sertoli cells regulate...
sperm development
123
Sertoli cells as sustentacular cells
provide sustenance and nourishment
124
Substances produced by sertoli cells
hormones (**activin, inhibin**), growth factors, enzymes, **androgen-binding protein** (binds to testosterone to keep it in the tubule lumen)
125
Spermatogonium location and fate
reside **inside basal lamina of seminiferous tubules,** some remain there to **undergo mitosis and produce more germ cells,** **others enter meiosis to become primary spermatocytes**
126
Location of spermatocytes as they differentiate (move towards _ _ as they become _ )
move towards **tubule lumen** as they become **sperm**
127
Once reaching lumen one spermatogonium becomes _ _
becomes **4 spermatids**
128
Spermatid location and fate
remain embedded in **apical membrane of sertoli cells** as they complete **transformation to sperm** (lose most cytoplasm and develop a flagellated tail)
129
Steps in spermatid to sperm
**chromatin condenses, microtubule extends, acrosome** (form cap over the nucleus), **mid piece** (store mitochondria for energy)
130
Time length of spermatogonia to sperm
**64 days (plus 12** for maturation in epididymis)
131
How is sperm moved out of tubule lumen?
**released from sertoli cells before maturity,** THEN other developing sperm, **bulk flow of other liquids, contraction of** smooth muscle cells (**myoid**)
132
**FSH** role in **spermatogenesis** (bind to receptors on _ cells to cause paracrine molecule generation needed for _ mitosis and _ . Also produce ABP and _ )
bind to receptors on **sertoli cells** to cause **paracrine molecule generation** needed for **spermatogonia mitosis** and **spermatogenesis,** also **produce ABP and inhibin**
133
LH role in spermatogenesis
target **interstitial leydig cells to cause testosterone production** (essential for spermatogenesis through sertoli cells, not sure how)
134
Testosterone from leydig cells is inhibitor of _ and _ release
**LH** and **GnHR** release
135
**Inhibin** from sertoli cells is inhibitor of _ release
**FSH** release
136
what is **Semen,** also prevents _
**liquid medium for delivering sperm (99% accessory gland secretions,** 1% sperm), also protects reproductive tract from pathogens ascending urethra **(prevents UTI)**
137
what are **Accessory gland secretions in sperm** (5)
**nutrients,** **buffers** (protect against acidic vaginal environment, residual acidic urine in urethra), **chemicals** (increase sperm motility), **prostaglandins** (motility, contraction of male and female reproductive tracts), **immunoglobulins/lysozymes**/antibacterial compounds
138
Androgens and primary sex characteristics
**internal sex organs** and **external sex organs** are **differentiated to male during embryonic development,** and their growth **after puberty** is **due to androgens**
139
Secondary sex characteristics influenced by androgens
body shape, facial/body hair growth, muscular development, vocal cord thickening, behavioural effects
140
Androgens ( _ hormones that promote _ synthesis)
**anabolic** hormones that promote **protein** synthesis (brain, heart, liver, kidneys, skin, bones)
141
Female external genitalia collectively referred to as
vulva
142
Vagina leads to...
uterus
143
Cervix is the opening of _
opening of uterus
144
**Uterus** (where _ _ implants and develops during pregnancy)
where a **fertilized egg** implants and develops during pregnancy
145
3 layers of uterus
**perimetrium** (**thin outer** connective tissue layer), **myometrium (thick** layer of smooth muscle), **endometrium** (inner layer)
146
Fallopian tubes
20-25cm long tubes that sperm swim into from uterus and proceed downward to fertilize egg
147
**Smooth muscle of fallopian tubes** ( _ layers, line with _ to move eggs to uterus once fertilized)
**2 layers,** similar to intestines and is lined with **cilia** to move eggs to uterus once fertilized
148
Fimbriae
extensions at end of fallopian tubes that **ensure eggs released from ovary enter the fallopian tube**
149
Ovary structure
dense connective tissue layer covering, thick outer cortex, inner portion is the **stroma** (medulla and cortex)
150
Ovary role
produce eggs and hormones
151
Time taken to complete maturation of primordial follicles
are recruited each cycle, take **1 year to mature**
152
**Development of secondary follicle** ( _ forms to become a _ follicle, one _ follicle fully develops)
**antrum** forms to become a **tertiary follicle,** one **single tertiary follicle** (dominant) **fully develops**
153
**Antrum** (storage of _, _, _ factors and regulatory factors needed for oocyte maturation, ovulation, and fertilization)
storage of **enzymes, hormones, growth factors** and regulatory factors needed for oocyte maturation, ovulation, and fertilization
154
Menstrual cycle
females produce mature gametes in monthly cycles (28 days, range of 24-35 days)
155
Phases of ovarian cycle
**follicular phase** (**follicular growth,** variable from 10 days - 3 weeks), **ovulation** (one or more follicles has ripened, the **ovary releases oocyte),** **luteal phase** (ruptured follicle **transforms to corpus luteum** which secretes hormones and ceases to function after 2 weeks if fertilization does not occur)
156
Tertiary follicle development in first 7 days
develop to form one dominant follicle, others undergo atresia
157
Phases of **uterine cycle**
**menses** (menstrual bleeding from uterus), **proliferative phase** (uterus adds **new cells to the endometrium layer in anticipation** of pregnancy), **secretory phase** (after ovulation hormones from **corpus luteum convert thickened endometrium layer into secretory structure**), if pregnancy does not occur the superficial layers are lost during menstruation and cycle repeats
158
Main hormone in proliferative phase ( _, drives _ of endometrium)
**estrogen,** drives **proliferation** of endometrium
159
Main hormone in secretory phase
**progesterone,** will convert endothelium into secretory structure
160
Hormones from ovary
estrogen, progesterone, inhibin, AMH
161
Dominant hormone in **follicular** phase
**estrogen**
162
Dominant hormone in **luteal** phase
**progesterone**
163
Ovulation is triggered by...
surges in LH and FSH
164
Hormones in **early to mid**-follicular phase
***FSH*** is released and several tertiary follicles mature, ***granulosa* (*FSH*)** and ***thecal* (*LH*)** cells produce hormones, **granulosa cells convert** **androgens (androstenedione) to *estrogens* (aromatase), *AMH*** prevents additional follicle recruitment, **estrogen** has negative feedback on anterior pituitary and positive feedback on granulosa cells, ***estrogen* causes endometrium proliferation**
165
Hormones in ***late follicular* phase and *ovulation***
***estrogen*** release peaks from follicles, some follicles undergo atresia while the dominant follicle persists, ***granulosa* cells release *progesterone* and *inhibin,*** **high estrogen has positive feedback on hypothalamus,** ***inhibin* causes *LH to surge*** to higher degree than FSH, **high estrogen readies endometrium for implantation**
166
When does ovulation occur? ( _ hours after _ peak)
**16-24** hours after **LH** peak
167
LH necessary for...
oocyte maturation
168
What resumes in ovulation?
**meiosis** (1st division to form secondary oocyte and polar body)
169
Mature follicle secretes _ and _ _ in ovulation
**prostaglandins** and **proteolytic enzymes**
170
Prostaglandins in ovulation
contribute to rupture of follicle and/or ovary wall
171
Proteolytic enzymes in ovulation
**breakdown collagen** and connective tissue holding the follicle together
172
Hormones in **early-mid luteal phase**
***thecal* and *granular cells*** turn into ***luteal cells* (LH),** ***lipid* and *glycogen* *accumulates* in cytoplasm and *secretes progesterone,*** **estrogen and progesterone levels rise** and give negative feedback to **hypothalamus** and **anterior pituitary,** **progesterone influences endometrium (secretory) in pregnancy preparation, cervical plug is formed** to prevent bacteria and sperm entrance
173
Corpus luteum life span
about 12 days
174
Hormones in **late luteal phase**
if **pregnancy does not occur** corpus luteum undergoes spontaneous apoptosis to become **corpus albicans**, ***progesterone/estrogen fall, LH/FSH increase,*** with **progesterone decreasing vessels in endometrium contract** and cause surface cells to die
175
When does menstruation begin? ( _ days after ovulation, _ days after corpus luteum ceases function)
14 days after ovulation, 2 days after corpus luteum ceases function
176
Contents of menstruation
40mL of blood, 35mL of serous fluid and cell debris
177
**Estrogen** influence on female secondary sex characteristics
breast development, patten of fat distribution to hips and upper thighs
178
**Androgen** influence on female secondary sex characteristics
pubic and armpit hair, libido (sex drive)
179
Requirements of procreation in terrestrial vertebrates (us)
internal fertilization - females have **receptacle for sperm**, males have **organ to deposit sperm** in receptacle
180
Procreation in humans (resting state)
male cannot be flaccid, penis must stiffen and enlarge (erection), sperm is released from male reproductive tract (ejaculation)
181
**Erection** pathway (parasympathetic or sympathetic?)
parasympathetic
182
Erection process
***ACh* from *parasympathetic* nerves bind *muscarinic ACh receptors* on endothelial cells,** ***NO* is produced by endothelial cells, NO enters smooth muscle cells** and **causes relaxation of vascular smooth muscle** **(*increased MLCP, decreased Ca+* in SR)**, engorgement compresses veins to prevent blood flow back
183
**Emission** pathway (parasympathetic or sympathetic?)
sympathetic
184
Emission
**movement of sperm** **out of the vas deferens and into the urethra** where it is joined by secretions from accessory glands to make semen
185
Ejaculation pathway ( _ )
somatic
186
Ejaculation
**expulsion of semen** (3 mL) by a **series of rapid muscular contractions** accompanied by sensations of pleasure
187
Erectile dysfunction
inability to achieve or sustain an erection, disrupts the sex act for men and women
188
ED caused by
**diabetes** (damage to nerves and vascular), **CVD and atherosclerosis** (ED is warning sign), **neurological disorders, drugs, alcohol, tobacco**
189
How does viagra work?
**inactivates phosphodiesterase 5 enzyme** that **converts cGMP back to GMP** (cGMP is needed to activate MLCP and increase SR Ca+ reuptake)
190
Female sexual dysfunction
low sexual desire
191
Treatments of female sexual dysfunction
***Flibanserin***/Addyi (**restore *prefrontal cortex* control over brains *motivation/reward pathways*** that enable sexual desire), androgen therapy, ***Bremelanotide***/Vyleesi (**synthetic hormone that acts in the *hypothalamus* where it targets the *melanocortin*** **receptor** believed to be involved in up-regulating a woman's sexual response to appropriate cues)
192
3 categories of contraceptive practices
**abstinence** (total avoidance of sexual intercourse), **sterilization** (tubal ligation or vasectomy), **interventional methods** (barrier methods, implantation prevention, hormonal treatments)
193
Most effectove contraceptive method
sterilization
194
2 kinds of sterilization
**tubal ligation** in females, **vasectomy** in males
195
Tubal ligation
fallopian tubes are cauterized, tied and cut, or banded to prevent the egg from fertilization
196
Vasectomy
vas deferens are cut and clamped to prevent sperm from reaching the urethra, semen is produced (just contains no sperm)
197
Ancient barrier methods
ancient egyptian vaginal plugs (leaves, feathers, figs held with crocodile and elephant dung, sea sponges soaked in vinegar, oil-soaked silk, rinses made of garlic, turpentine, and rose petals
198
Current contraceptive methods
diaphragm + contraceptive jelly, cervical cap + contraceptive jelly, sponge, female condom, male condom
199
Implantation prevention
**prevent the implantation of a fertilized egg** in the uterine wall, include **IUDs** and chemicals that change the properties of the endometrium
200
IUD
plastic devices (some wrapped in copper) that create a mild inflammatory reaction in the **endometrium that prevents the implantation of a fertilized egg** and also kills sperm
201
IUD side effects
pain, bleeding, infertility caused by PIV and blockage of the fallopian tubes
202
Techniques for decreasing gamete production depend on...
altering the hormonal environment of the body
203
Types of female hormonal treatments
pill, implant, patch, ring, hormonal IUD, injection
204
**Hormones in hormonal treatments** ( _/_ combinations inhibit gonadotropin secretion ( _ and _ ), _ thickens cervical mucus
**estrogen/progesterone** combinations inhibit gonadotropin secretion **(LH and FSH), progesterone** thickens cervical mucus
205
RISUG/Vasal Gel
**Reversible Inhibition of Sperm Under Guidance** as **polymer gel is inserted into vas deferens and blocks sperm** as they travel through (possibly do to pH or charge change)
206
Male hormone contraception (combination of _ and _ has complete suppression of spermatogenesis)
combination of **progestin** (negative feedback to stop spermatogenesis and androgen) and **androgens** (replenish androgens not produced), has complete suppression of spermatogenesis in 90% of males
207
Vaccines as hormone contraceptive
produce antibodies to ovum or sperm, was not effective and was ultimately abandoned
208
Small molecule inhibition of BRDT for contraception
blocks the driver of testis-specific gene expression and post-meiotic chromatin reorganization which disrupts spermatogenesis (is reversible)
209
Ouabain analogues as contraceptive
blocks Na,K-ATPase a4 isoform unique to sperm to stop sperms motility
210
Infertility
inability to conceive
211
Causes of male infertility
hormone-related, infections, retrograde ejaculation, antibodies to sperm
212
Types of hormone-related male infertility
low sperm count, abnormal sperm motility, abnormal sperm morphology
213
Causes of infection-related male infertility
STIs (chlamydia, gonorrhea) inflame epididymis/VD to cause sperm to degenerate, prostatitis and mumps interfere with spermatogenesis
214
Causes of low sperm count
low testosterone, abnormal LH/FSH secretions, defective valves
215
Defective valves
defective valves cause **varicocele veins to swell as blood pools** in them, may **increase temperature in testis** and lead to low sperm production and low sperm count
216
Retrograde ejaculation
**external urethral sphincter does not contract** and sperm goes up to bladder
217
Categories of female infertility causes
**damaged fallopian tubes** (STIs, surgery, pelvic tuberculosis), **ovulation disorders** (PCOS, hypothalamic dysfunction), premature ovarian insufficiency), **endometriosis, uterine/cervical disorders** (cervical stenosis)
218
Result of damaged fallopian tubes
scar tissue is formed to block FT and prevent sperm and egg from meeting
219
Result of PCOS
**increased androgen** production that **causes** lots of **tertiary follicles to form that do not develop** and instead **form polycystic ovaries**
220
Result of endometriosis
endometrium is produced outside of uterus and attracts immune cells which form scar tissue
221
Result of cervical stenosis
narrow cervix prevents sperm from swimming up into uterus and FT
222
Polyps in upper uterus
mess with sperm moving up and eggs moving down
223
Large polyps in uterus
prevent implantation
224
In vitro fertilization success rates
under 35 (over 50%), 35-37 (40%), 38-40 (25%), over 40 (8%)
225
Steps of in vitro fertilization
women is given hormone treatments to stimulate egg production, eggs are taken from woman's ovaries, eggs are mixed with sperm cells in dish to be fertilized, fertilized eggs are in incubator for 48 hours, embryos are implanted into uterus or are frozen for future implantation
226
Artificial insemination types
intracervical insemination, intratubal insemination, intrauterine insemination - when low sperm count
227
Capacitation
sperm sheds surface molecules (proteins and CHO) allowing them to rapidly swim to and penetrate egg
228
Capacitation depends on...
substances produced in the **uterus** (**albumin, lipoproteins, proteolytic enzymes)**
229
Aid in fertilization
chemical attractants produced by egg attract sperm to fertilize it
230
Egg viable to be fertilized for...
12-24 hours post-ovulation
231
Sperm remain viable in female reproductive tract for...
5-6 days
232
Fertilization occurs in...
distal portion of FT (100 sperm reach this point from millions in vagina)
233
3 main steps of fertilization
capacitation, acrosomal reaction, cortical reaction
234
Acrosomal reaction
to fertilize an egg sperm must penetrate granulosa cells and zona pellucida later using enzymes from acrosome to dissolve granulosa cell junctions and the zona pellucida
235
**Steps following acrosomal reaction** ( _ and _ plasma membranes fuse, _ reaction, _ nucleus moves into _ of egg, _ nucleus completes _ division, sperm and egg nuclei fuse to form _ nucleus)
**sperm and egg** plasma membranes **fuse,** **cortical reaction, sperm nucleus** moves **into cytoplasm of egg,** **oocyte nucleus** completes **meiotic division,** **sperm and egg nuclei fuse to form zygote** nucleus
236
Cortical reaction
sperm binds sperm-binding receptors to cause increased **IC Ca+** which releases **cortisol granules** to form hard, **impermeable zona pellucida** impermeable to other sperm
237
Purpose of cortical reaction
**prevent polyspermy** - fertilization of an egg by multiple sperm
238
Progesterone role in implantation (slows down smooth muscle _ in _ _ causing embryo to reach uterus _ days after fertilization as _ )
**slows down smooth muscle contraction in fallopian tubes** causing the **embryo to reach the uterus 7 days** after fertilization **as blastocyst**
239
Blastocyst structure
100 cells, outer layer (trophoblast) surrounds the inner cell mass
240
Time of blastocyst implantation
6-7 days post-ovulation
241
Implantation of blastocyst process (upon contact with _, _ proliferate and secrete proteolytic _ which break down the _ wall and allow the blastocyst to penetrate it and implant)
upon contact with **endometrium, trophoblasts** proliferate and secrete **proteolytic enzymes** which break down the **endometrium** wall and allow the blastocyst to penetrate it and implant
242
Chorion formation
outer cell layer of blastocyst forms an extra embryonic membrane (chorion - becomes placenta)
243
Inner cell mass of blastocyst forms...
embryo, amnion, allantois
244
Amnion secretes
secretes amniotic fluid
245
Allantois becomes
becomes part of the umbilical cord
246
Chorionic villi formation
outer layer of cells, **chorion,** that will become placenta **form villi that penetrate vascularized endometrium**
247
**Chorionic villi function** (**secrete enzymes** that break down the walls of maternal blood vessels to form _ _. Where nutrients, gases, and wastes exchange across _ membranes by diffusion)
secrete enzymes that break down the walls of maternal blood vessels to **form intervillous space** (cavity) where blood pool and baths villi, here **nutrients,** gases, and wastes **exchange across villi membranes by diffusion**
248
Placenta growth (width and % of maternal CO?)
20 cm in diameter, can receive 10% maternal CO
249
Human chorionic gonadotropin **(hCG)** (secreted by the _ _ of the developing placenta to prevent the _ _ from degenerating)
**secreted by** the **chorionic villi** of the developing placenta **to prevent the corpus luteum from degenerating**
250
hCG functions (bind _ receptors of _ _ and continue hormone secretion to keep the _ intact, stimulate _ production in developing male testes)
bind **LH** receptors of **corpus luteum** and continue **hormone secretion** to keep the **endometrium** intact, stimulate **testosterone** production in developing male testes
251
Hormone detected in pregnancy tests
human chorionic gonadotropin (hCG)
252
When does placenta take over hormone production from corpus luteum?
after 7 weeks
253
Hormones secreted by placenta
estrogen, progesterone, human placental lactogen
254
**Estrogen and progesterone from placenta** (provide _ feedback to _ axis which prevents follicle development)
**negative** feedback to **HPG axis** which prevents follicle development
255
**Estrogen** from **placenta** role
develop **milk secreting ducts** in breasts
256
**Progesterone from placenta** role
**maintains endometrium,** suppress contractions
257
Human placental lactogen initial assumed role
breast development during pregnancy and milk production
258
Human placental lactogen role (alters _ and _ metabolism; decreasess _ sensitivity, decreases _ )
alters mother's **glucose and FA metabolism** to support fetal growth (**decreases insulin sensitivity, increases lipolysis**)
259
Labor
rhythmic contraction of uterus
260
Potential causes of labor initiation signals
**drop in estrogen and progesterone** (in animals, not humans), **oxytocin** (does not increase until after labor starts), likely placenta releases **CRH** (corticotropin-releasing hormone)
261
Events in days leading up to labor
cervix softens and ligaments holding pelvic bones together loosens under enzymatic control (driven by estrogen or relaxin)
262
Fetus movement at initiation of contraction
repositions lower in abdomen putting pressure on and stretching cervix to initiate a **positive feedback loop**
263
Parturition feedback loop process
**pressure** on cervix from baby repositioning send signals to hypothalamus to **increase AP to *posterior pituitary* to cause *oxytocin release,*** oxytocin **causes contractions to increase which causes cervix to stretch further** which sends further signals
264
Mammary gland structure
each gland is made of **15-20 lobes,** each which are made of **lobules that are made of** **alveoli or acini cells** that **make and secrete milk,** lobes all enter into nipple
265
Estrogen in **puberty**
**stimulate growth** and **branching of milk ducts** **and** deposition of **fat**
266
Mammary gland development during pregnancy causes
estrogen, growth hormone, cortisol
267
Progesterone in breast development
convert epithelium into secretory structure
268
Colostrum (what do estrogen and progesterone do?)
initial fluid produced after birth as **estrogen and progesterone inhibit milk production,** contain high protein and maternal antibodies
269
Control of milk **production**
**prolactin** secreted from **anterior pituitary**
270
Control of prolactin
**prolactin inhibitory hormone (PIH) (dopamine - from Hypothalamus)** which begins to **drop later in pregnancy**
271
Oxytocin and milk
**causes milk ejection** (let down reflex) - **contraction of smooth muscle in breast** (myoepithelial) and uterus
272
Female puberty
budding breasts and first menstrual period, average age 12 (8-13)
273
Male puberty
subtle - growth and maturation of genitalia, pubic and facial hair, lowering of voice, change in body shape and height, age 9-14
274
Maturation of **hypothalamic-pituitary pathway** in puberty
**hypothalamic GnRH-secreting neurons increase their pulsatile secretion,** age is genetically programmed, adipose tissue in females will impact age of occurance
275
Menopause
**cessation of the female reproductive cycle when the ovaries no longer respond to gonadotropins,** occurs **40 years** after first menstrual cycle
276
Menopause symptoms (in absence of _ )
in the **absence of estrogen** - hot flashes, genitalia atrophy, osteoporosis
277
"Andropause"
**testosterone production decreases with age** (50% of **men over 50** have symptoms of andropause), **decrease in leydig cells**
