Reproduction Flashcards
1
Q
A 47 year old woman is seen in a ‘well woman’ clinic at her General Practitioner’s surgery. She reports that she has not had a menstrual period for three months and has no other symptoms. A pregnancy test is negative. Which is the primary physiological change that results in the menopause?
A
Reduced production of oestradiol (estradiol) and inhibin B by the ovary
2
Q
After embryo implantation the luteal phase supports the early days of the pregnancy through production of a hormone. Which hormone is produced?
A
Progesterone
3
Q
The Type B spermatogonium migrates through the blood-testis barrier. Into which of the following does Type B spermatogonium develop?
A
Primary spermatocytes
4
Q
Spermatids transform into spermatozoa. Which of the following is the term for this process?
A
Spermiogenesis
5
Q
Gametogenesis
A
Process by which gametes are produced in the reproductive organs (gonads) of an organism
6
Q
Oogenesis
A
Begins in fetal life
Significant milestones at puberty
Ceases at menopause
7
Q
Phases of menstrual cycle
A
Follicular phase = days 1-13/14
Ovulation = days 13/14
Literal phase = days 14-28
8
Q
What days are the follicular phase of the menstrual cycle
A
1-13/14
9
Q
What days are the ovulation phase of the menstrual cycle
A
13/14
10
Q
What days are the luteal phase of the menstrual cycle
A
14-28
11
Q
Primordial follicle
A
1 oocyte surrounded by granulosa cells
12
Q
What does the primordial follicle secrete
A
Oestrogen
Progesterone
Inhibin
13
Q
Primary follicle
A
Oocyte grows and separates from granulosa cells by the Zona pellucida
Contains glycoproteins
Used for binding sperm
14
Q
Preantral follicle
A
Granulosa cells differentiate into theca cells
2 cells function together for oestrogen synthesis
15
Q
Early antral follicle
A
Primary oocyte is full sized
Antrum forms
Filled with fluid secreted from granulosa cells
Progresses from the birth of the child to when that follicle enters the menstrual cycle years later
16
Q
Another name for mature follicle
A
Graafian follicle
17
Q
Mature follicle
A
After day 7 of the cycle
At the beginning of the cycle 10-15 preantral/early antral follicles develop and grow
After day 7 one follicle is dominant
18
Q
What happens to the non-dominant follicles
A
Undergo atresia (cell death)
19
Q
Dominant follicle
A
Increases in size as does its antrum from the increased fluid secretion
Oocyte emerges from meiosis arrest due to LH surge
Completes its secondary oocyte- this increases in size and balloons out of the ovary = ovulation
Enzymatic digestion ruptures the follicle and the oocyte is carried away by the antral fluid
20
Q
What does the dominant follicle depend on
A
Conditions and oestrogen production
21
Q
Stages of follicular phase and ovulation
A
Primordial follicle
Primary follicle
Preantral follicle
Early antral follicle
Graafian follicle
Ruptured follicle —> ovulation
Corpus luteum
Degenerating corpus luteum
Corpus albicans
22
Q
What do granulosa cells differentiate into
A
Theca cells
23
Q
What contains primary oocyte
A
Primordial follicle
24
Q
Luteal phase
A
After discharge the follicle collapses
Granulosa cells increase in size—> becomes the corpus luteum
Granulosa cells secrete oestrogen / progesterone and inhibin
25
What hormones do granulosa cells secrete
Oestrogen
Progesterone
Inhibin
26
If egg is not fertilised
After 10 days
The corpus luteum undergoes apoptosis triggering menstruation
Once it has collapsed it is called the corpus albicans - marks end of luteal ohase
27
What marks the end of the luteal phase
Collapsation of corpus luteum into corpus albicans
28
How long is it before the corpus luteum undergoes apoptosis if not fertilised
10 days
29
Uterine changes: menstrual phase days?
1-5
30
Uterine changes: menstrual phase
Withdrawal of progesterone leads to endometrial degeneration- trigger for menstrual flow
31
What causes the endometrial degeneration
Withdrawal of progesterone
32
Uterine changes: proliferative phase days?
5-14
33
Uterine changes: proliferative phase
Oestrogen from granulosa cells and theca cells causes the endometrium to thicken
Stimulates the myometrium
Also stimulates progesterone receptor generation in the endometrium
34
What does thickening of the endometrium stimulate
Myometrium
Progesterone receptor generation in the endometrium
35
Where is the site of fertilisation
Ampulla of fallopian tube
36
What hormone causes the endometrium to thicken
Oestrogen
37
Uterine changes: secretory phase days?
15-28
38
Uterine changes: secretory phase
Progesterone binds with its receptors in the endometrium
Endometrium secreted glycogen from glandular epithelium (also glycoproteins and mucopolysaccharides)
Provides a hospitable environment which is nourishing to sperm and oocyte
Progesterone overrides oestrogen to prevent myometrium contraction and prostaglandin secretion
39
At what stage does the follicle arrest at birth
Primordial follicle
40
What triggers further development of follicle from primordial arrest
FSH and LH secretion at sexual maturity
41
What do glandular epithelium cells in endometrium secrete
Glycogen (and glycoproteins and mucopolysaccharides)
42
What prevents myometrium contraction and prostaglandin secretion
Progesterone overrides oestrogen
43
During fetal life what happens to oocyte
Mitosis
44
At puberty what happens to primary oocyte
Meiosis I
45
When does meiosis II occur
After fertilisation
46
When does meiosis I occur
At puberty
47
Meiosis of primary oocyte produces
Secondary oocyte and polar body
48
Meiosis of secondary oocyte produces
Ovum and second polar body
49
What type of mucus is secreted when high oestrogen
Abundant clear and watery mucus
- good for sperm movement and implantation
50
What type of mucus is produced when there is progesterone and oestrogen
Thick and sticky
- stops bacteria entering and offer protection to the implanted egg
51
What hormones peak at ovulation
LH
FSH
oestrogen
52
Zona pellucida
Glycoprotein layer surrounding oocyte
53
Changes to uterus at days 1-5
Menstrual flow
Shedding of endometrium and small amount of blood
54
Where are LH and FSH produced
Pituitary gland
55
Changes to breasts at days 1-5
Reduction in swelling
Feeling of fullness
Sensitivity
Tenderness
56
When is it the most appropriate time for a woman to do a breast self-examination
Day 5 of menstrual cycle
57
Changes to uterus at days 6-7
Menstrual flow ceases
Repair of uterus begins with day 6 regrowth of endometrium
58
Changes to brain at days 6-7
GnRH from hypothalamus stimulates secretion of FSH and LH by pituitary
59
What stimulates secretion of FHS and LH
GnRH
60
Where is GnRH released from
Hypothalamus
61
Changes to ovary at days 6-7
FSH stimulates development of follicle and secretion of oestrogen
62
Changes to breasts at days 6-7
By day 7 breasts reach their minimum size
63
Changes to uterus at days 8-12
Growth in endometrium is stimulated by oestrogens
64
Changes to ovary at days 8-12
Increase in oestrogen secretion
65
Changes to brain at days 8-12
Decline in FSH and LH secretion due to negative feedback of oestrogen
66
Changes to brain at days 13-14
Surge in levels of FSH and LH secretion as a result of positive feedback of oestrogens
67
Changes to ovary at days 13-14
LH surge on day 14 causes ovulation
68
Which hormone surge causes ovulation
LH
69
Changes to brain at days 15-24
Decline in level of FSH and LH caused by return to negative feedback of oestrogen and progesterone
70
Changes to uterus at days 15-24
Progesterone produces changes making uterus ready to accept a fertilised ovum
71
Changes to ovary at days 15-24
Corpus luteum secretes increasing amounts of progesterone and oestrogen
72
Changes to ovary at days 25-28
Degeneration of corpus luteum and decline in progesterone and oestrogen
73
Changes to uterus at days 15-24
Because of lower progesterone levels, degenerative changes start taking place in endometrium— menstrual flow
74
Changes to breasts at days 15-24
Increasing feelings of fullness and swelling
Sensitive to touch
75
When are the breasts their minimum size
Day 7
76
2 hormones produced by ovaries
Oestrogen
Progesterone
77
Where is oestrogen produced in follicular phase
Granulosa cells
78
Where is oestrogen produced in luteal phase
Corpus luteum
79
Where is progesterone produced in follicular phase
Granulosa and theca cells- in small amounts
80
Where is progesterone produced in luteal phase
Corpus luteum in large amounts
81
Why is there are increase in FSH in the early part of the follicular phase
Due to the follicle developing from pre/early antral into a mature follicle
82
Levels of FSH in menstrual cycle
Increase in early part of follicular phase
Slow decrease throughout menstrual cycle
Increases on day 10/11
83
Why is there a slow decrease of FSH throughout the menstrual cycle
One follicle becoming dominant and the others dying
- as becomes dominant there is more oestrogen leading to a decrease in FSH
84
What leads to an increase in GnRH
Removal of oestrogen and progesterone
85
At what day is there an increase in FSH
10/11
86
Effect of FSH on theca cells
LH receptors develop
87
Why is the decrease in FSH greater than LH
Due to presence of Inhibin which actively inhibits the release of FSH
88
Function of Inhibin
Decreases FSH
89
When do inhibin levels peak
Ovulation
90
When do inhibin levels decrease
As the corpus luteum degenerwtes
91
Levels of LH during menstrual cycle
Constant for most of follicular phase
LH surge about 18 hours before ovulation
Decrease after ovulation
92
When does LH levels surge
18 hours before ovilagion
93
What generates the LH surge
High oestrogen levels from the maturing follicle
Acts in hypothalamus and anterior pituitary to increase sensitivity to GnRH (positive feedback)
94
Function of LH surge
Allows oocyte to complete meiosis I
95
Why is there a decrease in LH after ovulation
Production of progesterone - negative feedback on hypothalamus and anterior pituitary
96
Effect of LH in theca cells
Produce androgens
97
Androgens
Converted to produce oestrogen and antral fluid by granulosa cells
98
What maintains the corpus luteum
Low LH
99
Completion of meiosis I results in
Ovulation
100
What do granulosa cells produce
Oestrogen and inhibin
101
Negative feedback of oestrogen and progesterone
Decrease GnRH and so decrease FSH and LH after ovulation for 14 days
102
What does the corpus luteum secrete
Oestrogen
Progesterone
Inhibin
103
Withdrawal of what hormone causes menstrual bleeding
Progesterone
104
What maintains the corpus luteum in pregnancy
hCG
105
Location of spermatogenesis
Occurs entirely in testes
106
Meiotic divisions in spermatogenesis
Equal division of cells
107
Germ line epithelium in 1
Involved in gamete production
108
Number of gametes produced in spermatogenesis
4
109
Size of gametes produced in spermatogenesis
Sperm smaller than spermatocytes
110
Duration of spermatogenesis
Uninterrupted process
111
Onset of spermatogenesis
Begins at puberty
112
Release of spermatogenesis
Continous
113
End of spermatogenesis
Lifelong but reduces with age
114
Location of oogenesis
Occurs mostly in ovaries
115
Meiotic divisions in oogenesis
Unequal divisions of cytoplasm
116
Germ line epithelium in oogenesis
Not involved in gamete production
117
Number of gametes produced in oogenesis
One (plus 2-3 polar bodies)
118
Size of gametes in oogenesis
Ova larger than oocytes
119
Duration of oogenesis
In arrested stages
120
Onset of oogenesis
Begins in fetus (pre-natal)
121
Release of oogenesis
Monthly from puberty- menstrual cycle
122
End of oogenesis
Terminates with menopause
123
When is meiosis completed in oogenesis
After fertilisation
124
When is oogenesis first arrested
Prophase of meiosis I- maturation begins during menstrual cycle
125
When is oogenesis secondarily arrested
Metaphase of meiosis II until ovulation
126
Semen
Fluid and soerm
127
Normal sperm count
50-120 million/ml
128
Amount of semen expelled during orgasm
2-5ml
129
What percentage of semen secretions come from bulbourethral
10%
130
What percentage of semen secretions come from prostate
30%
131
What percentage of semen secretions come from seminal vesicles
60%
132
Where does semen come from
Bulbourethra
Prostate
Seminal vesicles
133
Functions of semen secretions
Buffers- protect against acidic environment
Chemicals to increase motility - fructose
Prostaglandins - stimulate female peristaltic contractions
134
What stimulates female peristaltic contractions
Prostaglandins
135
What does the bulbourethral gland release
Lubricating mucoid secretions
136
What do prostate and seminal vesicle secretions contain
Digestive enzymes
Fructose
Zinc
Citric acid
Prostaglandins
137
What increases motility of sperm
Fructose
138
Route of sperm
Seminiferous tubules
Rete testis
Efferent ducts
Epididymis
Vas deferens
Ejaculatory duct
Urethra
Penile urethra
139
Blood-testis barrier
Seminiferous tubule bound by a basement membrane
Sertoli cells extend from basement membrane into lumen
Joined by tight junctions
Unbroken ring inside seminiferous tubule
140
2 components of ring inside seminiferous tubule
Basal
Central
141
What forms the blood-testis barrier
Sertoli cells
142
Function of blood-testis barrier
Prevents movement of chemicals
Ensures proper conditions for development and differentiation
143
Length of sperm without fail
60 um
144
Length of sperm with tail
120 um
145
Head cap-acrosome of sperm
Contains special enzymes to penetrate wall of ovum
146
Parts of sperm
Head cap-acrosome
Head
Neck
Body
Tail
147
Body of sperm
Contains mitochondria for enegry
148
Length of spermatogenesis process
64 days
149
Where are spermatozoa produced
Testis
150
Spermatogonia
Undifferentiated sperm cells
151
What do spermatogonia divide into and when
Divide mitotically at puberty into 2 types
152
Type A spermatogonia
Remain outside the blood-testis barrier and produce more daughter cells
153
Type B spermatogonia
In basal compartment and are primary spermatocytes
154
What type of spermatogonia are the primary spermatocytes
Type B
155
Spermiogenesis
Occurs when the spermatic develop by growing tails and discarding the cytoplasm
Become spermatozoa
156
What causes release of sperm into lumen
Invaginations in Sertoli cells and when these retraction they release sperm
157
Sperm production
300-600 sperm per second per gram of testis
158
Structure of spermatozoa
Pear-shaped head
Haploid
Tip of nucleus covered with acrosome
Tail- flagellum
159
Feedback of spermatogenesis of HOG axis
Direct inhibition/ negative feedback on hypothalamus
Reduced receptor sensitivity to specific LH/FSH response to reduce hormone
160
How does testosterone inhibit LH secretion
Acts on hypothalamus to decrease amplitude of GnRH burst, resulting in decreased secretion
Acts directly in anterior pituitary to decrease LH response to GnRH
161
What do Sertoli cells produce
Inhibin
162
What do leydig cells produce
Testosterone
163
What does testosterone do
Stimulate Sertoli cells
Inhibitors LH secretion
164
What does inhibin do in males
Inhibit FSH production
165
FSH function in males
Stimulate Sertoli cells to carry out spermatogenesis
166
Development of spermatozoa
Spermatogonium
Spermatogonia type A/B
Commitment —> primary spermatocytes
Secondary spermatocytes
Spermatids
Spermatozoa
Activation mobile
167
At what stage of spermatogenesis does meiosis occur
Primary spermatocytes—-> secondary spermatocytes—> spermatids
168
When is sex determined
At fertilisation
169
How does Y chromosome cause a male
Contains SRY gene which leads to development of testis
170
If no SRY gene present
Ovary development
171
If SRY gene present
Testis development
172
Barr body
Non-functional X in female gonads condenses to form chromatin
173
What are genital organs formed from
Intermediate mesoderm from the genital ridge
174
At what week of embryology do the primordial gonads differentiate
Week 6
175
Double genital duct system
Wolffian ducts
Mullerian ducts
176
Where do germ cells for sperm and ova come from
Yolk sac of hindgut
177
In males which duct system stays
Wolffian duct (Mullerian regresses)
178
What do Sertoli cells produce in males
Mullerian inhibitory factor
179
What induces production of MIF
SRY gene
180
Testosterone and Wolffian ducts
Converts into epididymis, vas deferens, ejaculatory duct and seminal vesicle
181
What does Mullerian inhibitory factor lead to
Testis determining factor which influences formation of male gonads
182
What is found deep in the medulla of the testis
Cord of testis
183
Rete testis
At hilum of testis there are multiple tubes
184
Tunica albuginea
Dense connective tissue under the epithelial in testis
185
Function of DHT (from testosterone )
Development of penis, scrotum and prostate
186
What causes the testes to descend into the scrotum
Testosterone
187
Which duct is present in females
Mullerian duct
188
What does the Müllerian duct form
Fallopian tubes
Uterus
Upper 2/3 vagina
189
What forms the lower 1/3 vagina and external genitalia
Urogenital sinus
190
Week 7 of female development
2nd generation cords penetrate underlying mesenchyme
191
Month 3 of female development
Cords split into isolated clusters with surround oogonium and follicular cells
192
What does oestrogen help to form in female development
Uterine tubes
Uterus
Cervix
Vagina
Labia minora and majora
Clitoris
193
Size of testes
4cm long and 2.5 cm diameter
Oval organ
194
Tunica vaginalis
Sac-like extension of peritoneum covering testes anteriorlu
195
Pendulous pouch
Holds the testes
196
Why is testicular thermoregulation necessary
Sperm not produced at core body temperature
197
How is testicular thermogenesis carried out
Heat exchange of pampiniform plexus
198
At what temperature is sperm produced
35
199
Median septum
Divided pendulous pouch of testes
200
What changes transform spermatids into spermatozoa
Discarding excess cytoplasm and growing tails
201
How is the sperm tail divided
Midpiece
Principal piece
Endpiece
202
Midpiece of tail
Contains mitochondria around axoneme of the flagellum
203
Principal piece of tail
Axoneme surrounded by fibres
204
Endpiece of tail
Axoneme only
very narrow tip of flagellum
205
Length of ejaculatory duct
2cm
206
Location of leydig cells
Clusters of cell between the seminiferous tubules
207
Function of Sertoli cells
Promote sperm cell development
208
What do seminiferous tubules drain into
Rete testis
209
Where does meiosis occur in males
Seminiferous tubules
210
Meiosis I in males forms
2 secondary spermatocytes
211
Meiosis II in males forms
4 spermatids
212
What forms the blood-testis barrier
Tight junctions between Sertoli cells
Basement membrane
213
Efferent ductules of spermatic ducts
12 small ciliated ducts collecting sperm from the Rete testis and transporting it to the epididymis
214
Structure of epididymis
6cm long coiled duct adhering to posterior testis
Head , body and tail
215
Function of epididymis
Site of sperm maturation and storage
216
How long are sperm fertile for
40-60 days
217
Vas deferens
Muscular tube passing up from scrotum through inguinal canal to posterior surface of bkadder
45cm long
Widens into a terminal ampulla
218
Ejaculatory duct
2cm duct formed from vas deferens and seminal vesicle
Passes through prostate to empty into urethra
219
Amount of semen expelled during orgasm
2-5 ml
220
What sperm count is associated with infertility
<25 million/ml
221
Composition of semen
60% seminal vesicle fluid
30% prostatic
10% sperm
Trace of bulbourethral fluid
222
Other components of semen
Fructose (energy for sperm motility)
Fibrinogen
Clotting enzymes
Fibrinolysin
Prostaglandins
Spermine
223
Function of clotting enzymes in semen
Convert fibrinogen to fibrin causing semen to clot
224
Function of fibrinolysin in semen
Liquefied semen within 30 mins
225
Function of prostaglandins in semen
Stimulate female peristaltic contractions
226
Function of spermine in semen
Base stabilising sperm pH at 7.2-7.6
227
What is sex determined by
The type of sperm fertilising the egg I.e. 50% XY and 50% XX
228
What is the name of the peptide hormone which play a major role in both ovulation and the activity of the interstitial cells of the testis?
Luteinising hormone LH
229
Which peptide hormone formed in the hypothalamus is necessary for normal spermatogenesis?
Gonadotropin-releasing hormone (GnRH)
230
Anovulation
anovulatory cycle is a menstrual cycle in which ovulation, or the release of an egg from the ovaries, does not occur. Anovulation is often due to hormonal imbalances that can be the result of using hormonal birth control, being underweight or overweight, exercising excessively, or experiencing significant stress.
231
Which one of the following statements is correct? Sperm capacitation is a process that___
Prepares spermatozoa in vivo for fertilisation
232
What are Sertoli cells
Phagocytes
233
Which cells contain Reinke’s crystalloids
Leydig cells
234
Where do Sertoli cells lie
Against basement membrane of seminiferous tubules
235
What stimulates leydig cells to secrete testosterone
Luteinising hormone LH
236
What type of mitochondria are found in spermatozoa
Spiral mitochondria
237
How much does the normal adult testis weigh
15-19 g
238
The rete testis lies between which two structures?
Straight tubule and epididymis
239
What are the prostate’s secretions rich in
Acid phosphatase
240
Where is lipofuscin found
Seminal vesicles epithelium
241
Does the prostate have a well-defined or poorly defined capsule
Poorly defined
242
How many primordial follicles are present in the ovary at birth?
400000
243
Proliferative endometrium is characterised by the presence of:
Stromal mitotic figures
244
Proliferative endometrium
glands are straight, do not have secretions, are not vacuolated and there are mitoses in stromal and glandular epithelial cells
245
Early secretory phase endometrium
prominent subnuclear glycogen vacuoles and the lack of secretions
246
Which of the following is lined by stratified squamous keratinising epithelium with hairs?
A.Clitoris
B.Hymen
C.Labia majora
D.Labia minora
E.Vagina
Labia majora
247
Development of female gonads
The gonads begin as genital rigid (a pair of longitudinal ridges derived from intermediate mesoderm and overlying epithelium). In the 4th week , germ cells begin to migrate from the endoderm lining of the yolk sac to the genital ridges via the dorsal mesentery of the hindgut: reaching the genital ridges in the 6th week. Simultaneously the epithelium of the genital ridges proliferates and penetrates the intermediate mesoderm to form the primitive sex cords.
Due to the lack of the SRY gene, the primitive sex cords degenerate. The epithelium of the gonad continues to proliferate, producing cortical cords, which in the third month, break up into clusters, surrounding each oogonium with a layer of epithelial follicular cells, forming a primordial follicle.
The gonads arise in the upper lumbar region and are tethered to the labia by the gubernaculum. The ovaries migrate caudally and the gubernaculum becomes the ovarian ligament and round ligament of the uterus.
248
Development of female internal genitalia
In the first weeks of urogenital development, all embryos have 2 pairs of ducts, both ending at the cloaca, called the Mesonephric (Wolffisn) ducts and paramesonephric (Mullerian) ducts. In the female, there are no leydig cells to produce testosterone. In the absence of testosterone, the Wolffian ducts degenerate, leaving behind a vestigial remnant called the Gartner’s duct. Also, the absence of anti-Mullerian hormone allows for the development of the Müllerian ducts. They have 3 parts:
1. Cranial- becomes the fallopian tubes
2. Horizontal- becomes the fallopian tubes
3. Caudal- fuse to form the uterus, cervix and upper 1/3 of the vagina
The lower 2/3 of vagina is formed by sinovaginal bulbs derived from the pelvic part of the urogenital sinus
249
Development of female external genitalia
Development begins in the third week when mesenchymal cells from the primitive streak migrate to the cloacal membrane to form a pair of cloacal folds. Cranially, these folds fuse to form the genital tubercle. Caudally, they divide into the urethral folds and anal folds. Genital swellings develop either side of the urethral folds.
Oestrogen causes the genital tubercle to elongate slightly to form the clitoris. The urethral folds and genital swellings do not fuse, forming the labia minora and majora. The urogenital groove remains open, forming the vestibule into which the urethra and vagina open.
250
Effect of pituitary hormones on ovaries
Gonadotropin releasing hormone (GnRH) from the hypothalamus stimulates luteinising hormone and follicular stimulating hormone release from the anterior pituitary gland. FSH binds to granulosa cells to stimulate follicle growth, permit the conversion of androgens (from theca cells) to oestrogens and stimulate inhibin secretion. LH acts on theca cells to stimulate oestrogen production and secretion of androgens. The LH surge in the middle of the menstrual cycle stimulates ovulation and it maintains the corpus luteum for 10 days following ovulation.
251
Effect of ovarian hormones in endometrium, cervix and vagina
Proliferative Phase:
• Following menses, the proliferative phase runs alongside the follicular phase, preparing the reproductive tract for fertilisation and implantation. Oestrogen initiates fallopian tube formation, thickening of the endometrium, increased growth and motility of the myometrium and production of a thin alkaline cervical mucus (to facilitate sperm transport).
Secretory Phase:
• The secretory phase runs alongside the luteal phase. Progesterone stimulates further thickening of the endometrium into a glandular secretory form, thickening of the myometrium, reduction of motility of the myometrium, thick acidic cervical mucus production (a hostile environment to prevent polyspermy), changes in mammary tissue and other metabolic changes.
Menses:
• Menses marks the beginning of a new menstrual cycle. It occurs in the absence of fertilisation once the corpus luteum has broken down and the internal lining of the uterus is shed. Menstrual bleeding usually lasts between 2-7 days with 10-80ml blood loss.
252
Phases of coitus
Excitement
Plateau
Orgasmic
Resolution
253
Excitement phase in males
Sacral parasympathetic neurons
• arteriolar vasodilation in corpora cavernosa increasing penile blood flow
• Penile filling (latency)
• Penile tumenscence (erection)
254
Excitement phase in females
Sacral parasympathetic neurons
• vasocongestion
• Vaginal lubrication
• Clitoris engorges with blood, uterus elevates
• Increased muscle tone, heart rate and bp
• inner 2/3 of vagina lengthens and expands
255
Plateau phase in males
Sacrospinous reflex
• contraction of ischiocavernosa- venous engorgement and decreased arterial inflow
• Testes become engorged and elevated
• Stimulates secretions from accessory glands
• Lubricates distal urethra and neutralises acidic urine in urethra
256
Plateau phase in females
Sacrospinous reflex
• labia minora deepens in colour
• Clitoris withdraws under hood
• Bartholin’s glands secrete to lubricate vestibule
• Uterus fully elevates
257
Orgasmic phase in males
Emission = thoracolumbar sympathetic reflex
• contraction of smooth muscles in ductus deferens, ampulla, seminal vesicle and prostate
• Semen pooled in urethral bulb
Ejaculation = spinal reflex with cortical control (L1, L2 sympathetic)
• contraction of glands, ducts and urethral sphincter
• Filling of internal urethra stimulates pudendal nerve- contraction of genital organs, ischiocavernosa and bulbocavernosa
258
Orgasmic phase in females
Spinal reflex with cortical control (L1,L2 sympathetic)
• orgasmic platform (in lower 1/3 of vagina) contracts rhythmically 3-15 times
• Uterus and anal sphincter contract
259
Resolution phase in males
Thoracolumbar sympathetic pathway
• arteriolar vasoconstriction
• Increased venous return
Refractory period
260
Resolution phase in females
Thoracolumbar sympathetic pathway
• clitoris descends and engorgement subsides
• Labia return to unaroused colour and size
• Uterus descends
• Vagina shortens and narrows
• No refractory period unlike in males
261
Polycystic ovary syndrome is a common hormonal disorder.
Which of these symptoms is not associated with Polycystic Ovary Syndrome
A. Depression
B. Galactorrhoea
C. Hirsutism
D. Obesity
E. Oligomenorrhoea
B - galactorrhoea
262
A 55-year-old woman presents with vaginal dryness as part of her menopausal symptoms.
Which of these terms best describes the epithelium of the vagina?
Non-keratinised stratified squamous epithelium
263
22 year old woman underwent menarche at the age of 12. She last had a period 14 months ago. She is not pregnant and has never been pregnant before.
Which phrase best describes her current condition?
Secondary amenorrhoea
264
Oligomenorrhoea
abnormally infrequent menstruation (intervals of greater than 35 days)
265
Primary amenorrhoea
failure to establish menstruation by the time of expected menarche (e.g. by age 15 with normal secondary sexual characteristics)
266
Secondary amenorrhoea
cessation of menstruation in a woman with previously normal menses
267
Menorrhagia
regular excessive menstrual blood loss that interferes with a woman’s physical, social emotional well being
268
Secondary infertility
inability to become pregnant or carry a baby to term after previously giving birth to a baby
269
Rudge and Hannah have been trying for many years to have a baby however upon examination they have found Rudge is infertile due to low sperm production. Where is the main site for spermatogenesis
Seminiferous tubules
270
Which one of the following statements isn’t true about LH
Granulosa cells secrete inhibin which mainly inhibits LH (FSH)
