3: Anatomy and Physiology Flashcards
1
Q
Name the bones of the pelvis.
A
- two hip bones called the innominate bones (also known as ox coxae)
- sacrum
- coccyx
The innominate bones consist of the pubis, the ischium, and the ilium, all of which are fused together at the acetabulum. The ilium comprises the posterior and upper portion of the innominate bone, forming what is known as the iliac crest. It articulates with the sacroiliac joint posteriorly, and together with its ligaments is the major contributor to pelvic stability. The pubic bones articulate anteriorly with the symphysis pubis and, with their inferior angles from the descending rami, form the important bony landmark of the pubic arch. The ischial spines are bony prominences that are clinically important because they are used as landmarks when performing pudendal blocks and in other medical procedures such as sacrospinous ligament suspension. The ischial spines are also used to assess progression of fetal descent during childbirth.
2
Q
What does the iliac crest articulate with?
A
Sacroiliac joint posteriorly
3
Q
What provides the majority of pelvic stability?
A
The ilium comprises the posterior and upper portion of the innominate bone, forming what is known as the iliac crest. It articulates with the sacroiliac joint posteriorly, and together with its ligaments is the major contributor to pelvic stability.
4
Q
Which bones are used as landmarks when performing pudendal blocks and other medical procedures such as sacrospinal ligament suspension?
A
Ischial spines
5
Q
Which bones are used to assess progression of fetal descent during childbirth?
A
Ischial spines
6
Q
The _____ and the _____ shape the posterior portion of the pelvis.
A
The sacrum and the coccyx shape the posterior portion of the pelvis.
7
Q
The sacrum is formed by the fusion of the _____, which includes the important bony landmark of the sacral promontory, and joins the coccyx at the sacrococcygeal symphysis.
A
The sacrum is formed by the fusion of the five sacral vertebrae, which includes the important bony landmark of the sacral promontory, and joins the coccyx at the sacrococcygeal symphysis.
8
Q
The coccyx is formed by the fusion of _____, is usually movable, and is itself a key bony landmark.
A
The coccyx is formed by the fusion of four rudimentary vertebrae, is usually movable, and is itself a key bony landmark.
9
Q
The _____ constitutes the bony passageway through which the fetus must maneuver to be born vaginally.
A
The true pelvis constitutes the bony passageway through which the fetus must maneuver to be born vaginally.
10
Q
What is the best-known classification of the female pelvis and what characteristic is used for classification?
A
- Caldwell-Moloy
- Posterior segment of the inlet
11
Q
Name the 4 basic pelvic types.
A
- Gynecoid
- android
- anthropoid
- platypelloid
12
Q
T/F Most pelvises are one of the 4 main types.
A
False. Most pelvises are a mixture of types.
13
Q
Name the 3 pelvic support structures.
A
- muscles and connective tissue of the pelvic floor
- fibromuscular tissue of the vaginal wall
- endopelvic connective tissue
14
Q
Where does the obturator internus muscle exit the pelvis?
A
Lesser sciatic foramen
15
Q
Pouch that lies superiorly to the perineal membrane.
A
Deep perineal space
16
Q
A sheet made up of dense fibrous tissue that spans the opening of the anterior pelvic outlet.
A
Perineal membrane (or urogenital diaphragm)
17
Q
The most important muscle of the pelvic floor.
A
Levator ani muscle
18
Q
The pubococcygeus, puborectalis, and iliococcygeus are the primary components making up what muscle?
A
Levator ani muscle
19
Q
The _____ or sphincter vaginae fibers form the sling around the vagina and originate from the posterior surface of the pubis; they insert in the perineal body.
A
The levator prostatae or sphincter vaginae fibers form the sling around the vagina and originate from the posterior surface of the pubis; they insert in the perineal body.
20
Q
The _____ are important in maintaining fecal continence; they originate from the posterior surface of the pubis and form a sling around the rectum.
A
The puborectalis fibers are important in maintaining fecal continence; they originate from the posterior surface of the pubis and form a sling around the rectum.
21
Q
The _____ originate from the posterior surface of the pubis and insert into the anococcygeal rapine.
A
The pubococcygeus fibers originate from the posterior surface of the pubis and insert into the anococcygeal rapine.
22
Q
The _____ originate from the obturator internus fascia and the ischium and insert into the anococcygeal rapine.
A
The iliococcygeus fibers originate from the obturator internus fascia and the ischium and insert into the anococcygeal rapine.
23
Q
The fan-shaped _____ lies anterior to the sacrospinous ligament, originates from the ischial spine, inserts into the lower part of the sacrum and coccyx, and works synergistically to aid the levator ani muscle.
A
The fan-shaped coccygeus muscle lies anterior to the sacrospinous ligament, originates from the ischial spine, inserts into the lower part of the sacrum and coccyx, and works synergistically to aid the levator ani muscle.
24
Q
The_____ contracts to cause erection of the clitoris during sexual arousal.
A
The ischiocavernous muscle contracts to cause erection of the clitoris during sexual arousal.
25
The externally visible outer genitalia.
Vulva
26
Name the components of the vulva.
1. Mons pubis
2. Labia minora
3. Labia majora
4. Clitoris
5. Urinary meatus
6. Vaginal opening
7. Corpus spongeosum erectile tissue (vestibular bulbs) of the labia minora and perineum
27
The _____ is inside the labia minora and outside the hymen.
The **_vestibule_** is inside the labia minora and outside the hymen.
28
On each side of the vestibule is a \_\_\_\_\_, which secretes lubricating mucus into the introitus during sexual excitement.
On each side of the vestibule is a **_Bartholin’s gland_**, which secretes lubricating mucus into the introitus during sexual excitement.
29
The mound-like pad of fatty tissue that covers and protects the symphysis pubis.
Mons pubis
30
They assist in keeping the vaginal introitus closed, which in turn helps prevent infection.
Labia majora
31
Smaller, nonfatty folds covered by non-hair-bearing skin laterally and by vaginal mucosa on the medial aspect.
Labia minora
32
What are normal colors for the labia?
1. Light pink
2. Dark pink
3. Shades of gray
4. Peach
5. Brown
6. Black
33
The labia minora are usually more prominent in _____ and women who are \_\_\_\_\_.
The labia minora are usually more prominent in **_children**_ and women who are _**postmenopausal_**.
34
A sensitive organ that is typically described as the female homologue of the penis in the male.
Clitoris
35
It is formed from the genital tubercle. It is **1.5 to 2 cm** in length, consists of two crura and two corpora cavernosa, and is covered by a sensitive rounded tubercle known as the glans
Clitoris
36
Organ that consists of two paired erectile chambers and is located at the superior portion of the vestibule.
Clitoris
37
What is formed in part by the fusion of the upper part of the two labia minora?
Clitoral hood
38
Which arteries provide blood supply to the clitoris?
Dorsal and clitoral cavernosal arteries
39
Which 2 parts play a critical role in sexual activity?
1. Labia minora
2. Clitoris
40
Age-associated female sexual dysfunction from decreased clitoral sensitivity may be associated with histologic changes in \_\_\_\_\_.
Age-associated female sexual dysfunction from decreased clitoral sensitivity may be associated with histologic changes in **_clitoral cavernosal erectile tissue_**.
41
Periurethral glands which release mucus, form a triangular area of mucous membrane surrounding the urethral meatus from the clitoral glans to the vaginal upper rim or caruncle.
Skene's glands (2 of them)
42
The pea-sized vestibular glands are located at about the **4 and 8 o’clock positions** in the vulvovaginal area, just beneath the fascia.
Bartholin's glands
43
Where are the 2-cm openings of the Bartholin's glands?
They open into a groove between the **labia minora** and **hymen**.
44
What type of cells make up Bartholin's glands?
Columnar cells
45
A short conduit, approximately **3 to 5 cm long**, extending from the base of the bladder and exiting externally to the vestibule.
Urethra
46
What type of cells make up the urethra?
The urethral mucosa is composed of **stratified transitional epithelium** near the urinary bladder; the rest of this structure is lined by a **stratified squamous epithelium**.
47
A circular band of skeletal muscle that forms the sphincter urethrae, better known as the external urethral sphincter.
Urogenital diaphragm
48
Paired organs that resemble a large almond in terms of their size and configuration.
Ovaries
49
What is the approximate size of an ovary?
1.5 cm x 2.5 cm x 4 cm
50
What is the approximate weight of an ovary?
3-6 grams
51
The ovaries produce _____ and the sex hormones known as _____ and \_\_\_\_\_.
The ovaries produce **_gametes (also known as ova)_** and the sex hormones known as **_estrogen_** and **_progesterone_**.
52
T/F The color and texture of sex organs change with a woman’s age and reproductive stage.
True
53
Where are the ovaries in a nulliparous woman situated?
A shallow depression called the **ovarian fossa**, located on either side of the uterus in the upper pelvic cavity.
54
The _____ is the principal supporting membrane of a woman’s internal genital organs, including the fallopian tubes and uterus.
The **_broad ligament_** is the principal supporting membrane of a woman’s internal genital organs, including the fallopian tubes and uterus.
55
What are the 3 parts of an ovary?
1. **Outer cortical region (cortex)**, which contains germinal epithelium with oogonia and ovarian follicles that number approximately 400,000 at the initiation of puberty.
2. **Medullary region (medulla)**, which consists of connective tissue, myoid-like contractile cells, and interstitial cells.
3. **Hilum**, which is the point of entrance for all of the ovarian vessels and nerves.
56
The nerve fibers to the ovaries innervate only the vascular networks, and not the \_\_\_\_\_.
The nerve fibers to the ovaries innervate only the vascular networks, and not the **_stroma_**.
57
Paired narrow muscular tubes that extend approximately **10 cm** from each cornu of the body of the uterus, outward to their openings near the ovaries.
Fallopian tubes
58
Name the 4 segments of the fallopian tubes.
1. The **pars interstitialis** (intramural portion) penetrates the uterine wall. It contains the fewest mucosal folds, with the myometrium contributing to its muscularis.
2. The **isthmus**, the narrow segment adjacent to the uterine wall, contains few mucosal folds.
3. The middle segment, known as the **ampulla**, is the widest and longest segment. It contains extensive branched mucosal folds and is the most common site of fertilization.
4. The **infundibulum**, the funnel-shaped distal segment, opens near the ovary but is not attached to it (Katz, 2012). Very fine fingerlike fronds of its mucosal folds, known as fimbriae, project from the opening toward the ovary to help direct the oocyte into the lumen of the fallopian tube.
59
How do the ova move down the fallopian tubes?
Cilia that cover the fallopian tubes.
60
What are the 3 layers of the wall of the fallopian tube?
1. Mucosa (internal)
2. Muscularis (middle)
3. Serosa (outer)
61
Which arteries supply blood to the fallopian tubes?
1. Ovarian artery
2. Uterine artery
62
A muscular, inverted, pear-shaped, hollow, thick-walled organ that opens to the vagina at the cervix and then widens toward the top where the uterine tubes enter.
Uterus
63
Name the 3 anatomic regions of the uterus.
1. Fundus
2. Body
3. Cervix
64
When the _____ is empty, the uterus angles forward over it. As it fills, the uterus is lifted dorsally and may become retroflexed, pressing against the rectum.
When the **_bladder_** is empty, the uterus angles forward over it. As it fills, the uterus is lifted dorsally and may become retroflexed, pressing against the rectum.
65
What is the approximate size of a nulliparous uterus?
8 cm long x 5 cm wide x 2.5 thick
66
How much does a nulliparous uterus weigh?
40-50 grams
67
What are the 3 layers of the uterine wall?
1. Endometrium
2. Myometrium
3. Serosa (adventitia)
68
What type of cells make up the uterine mucosa?
Simple columnar epithelium supported by a lamina propria
69
The _____ is the temporary layer at the luminal surface that responds to ovarian hormones by undergoing cyclic thickening and shedding.
The **_stratum functionale_** is the temporary layer at the luminal surface that responds to ovarian hormones by undergoing cyclic thickening and shedding.
70
The\_\_\_\_\_ is the deeper, thinner, permanent layer that contains the basal portions of the endometrial glands.
The **_stratum basale_** is the deeper, thinner, permanent layer that contains the basal portions of the endometrial glands.
71
This layer is retained during menstruation.
Stratum basale
72
The _____ receives a double blood supply: uterine arteries that bifurcate into straight arteries to the stratum basale and coiled arteries to the functionalis.
The **_endometrium (of the uterus)_** receives a double blood supply: uterine arteries that bifurcate into straight arteries to the stratum basale and coiled arteries to the functionalis.
73
During the cyclic shedding of the functionalis, which blood supply is retained and which is lost?
**Straight** arteries are **retained** while the **coiled** are **lost**.
74
It is made mostly of dense connective tissue, is usually **2.5 to 3 cm in length**, and is covered interiorly by a mucus-secreting ciliated epithelium at the upper regions and by stratified squamous epithelium at the bottom end.
Cervix
75
The opening of the cervix into the vagina occurs at almost a _____ to the long axis of the vagina.
The opening of the cervix into the vagina occurs at almost a **_right angle_** to the long axis of the vagina.
76
A thin-walled tube extending from the external vulva to the cervix
Vagina
77
T/F The vagina touches the empty bladder on the **ventral** and **superior** surface.
True
78
The internal mucosal layer of the vagina contains traverse folds, known as \_\_\_\_\_. This muscular canal extends from the midpoint of the cervix to its opening located between the urethra and the rectum. The mucous membrane lining the vagina and musculature is continuous with the uterus. The vaginal walls can be easily separated because their surfaces are normally moist, lubricated by a _____ vaginal fluid.
The internal mucosal layer of the vagina contains traverse folds, known as **_rugae**_. This muscular canal extends from the midpoint of the cervix to its opening located between the urethra and the rectum. The mucous membrane lining the vagina and musculature is continuous with the uterus. The vaginal walls can be easily separated because their surfaces are normally moist, lubricated by a _**basal_** vaginal fluid.
79
To a much lesser degree than seen in the skin, this vaginal epithelium undergoes hormone-related cyclic changes, including slight _____ of the superficial cells during the menstrual cycle
To a much lesser degree than seen in the skin, this vaginal epithelium undergoes hormone-related cyclic changes, including slight **_keratinization_** of the superficial cells during the menstrual cycle
80
Does the vaginal epithelium secrete mucus?
No, the epithelium has no glands, so it does not secrete mucus.
81
How does the vaginal wall thicken? What does this do to vaginal ph?
Release of estrogen causes the epithelium to thicken, differentiate, and accumulate glycogen. Vaginal bacteria metabolize the glycogen to lactic acid, causing the typically low pH of the vaginal environment.
82
Large, modified sebaceous glands contained within superficial fascia.
Breasts
83
5 components of breasts.
1. Nipple
2. Lobes
3. Ducts
4. Fibrous tissue
5. Fatty tissue
84
T/F The number of lobes determines breast size.
False. It is unrelated.
85
How many lobes in each breast?
Each breast is composed of **12 to 20 lobes** of glandular tissue.
86
How many passages are there through the breast?
Each lobe empties into a single lactiferous duct, so there are **12-20 per breast** (and just as many in the nipple).
87
\_\_\_\_\_ ligaments connect the chest wall to the skin of the breast, giving the breast its shape and elasticity.
**_Cooper’s_** ligaments connect the chest wall to the skin of the breast, giving the breast its shape and elasticity.
88
In a nonpregnant woman, does the fatty tissue or glandular tissue affect breast size?
Fatty tissue
89
Pigmented area surrounding the nipple.
Areola
90
The nipple and areola are made of _____ and feature a thick network of nerve endings.
The nipple and areola are made of **_smooth muscle fibers_** and feature a thick network of nerve endings.
91
What protects and lubricates the nipple during lactation?
Oil-producing Montgomery's glands
92
Discuss the reproductive hormones responsible for breast development during puberty and lactation.
**Prolactin (PRL)** and **growth hormone (GH)** from the anterior lobe of the pituitary stimulate mammary gland development. These hormones are aided by **human placental lactogen** from the placenta, which stimulates the mammary gland ducts to become active during pregnancy. **Estrogen** promotes the growth of the gland and ducts, while **progesterone** stimulates the development of milk-producing cells. **Prolactin**, which is released from the anterior pituitary, stimulates milk production. **Oxytocin**, which is released from the posterior pituitary in response to suckling, causes milk ejection from the lactating breast.
93
T/F Although the main flow moves toward the axilla and anterior axillary nodes, lymph drainage has been shown to pass in all directions from the breast.
True
94
When do menstrual cycles begin and end?
Typically start 12-15 years of age and end 45-55.
95
It is now believed that _____ is critically important in determining the onset of puberty and menstruation in young women.
It is now believed that **_body composition_** is critically important in determining the onset of puberty and menstruation in young women.
96
Who tends to have an earlier onset of menarche?
The ratio of total body weight to lean body weight is probably the most relevant factor, and individuals who are **moderately obese** (i.e., 20–30% above their ideal body weight) tend to have an earlier onset of menarche.
97
What is the "normal" menstrual cycle?
* Frequency
* Cycle variation over 12 months
* Duration of flow
* Amount of flow
1. Frequency: 21-35 days (pg 88) or 24-38 (pg 576)
2. Cycle variation over 12 months: Variation less than 20 days
3. Duration of flow: 4-6 days (though 2-8 days still considered normal. pg 88) or 4.5-8 days (pg 576)
4. Amount of flow Avg of 50mL (20-80 mL pg 88) or 5-80 mL (pg 576)
98
When are menstrual cycles frequently irregular and why?
Menstrual cycles that occur during the first 1 to 1.5 years after menarche are frequently irregular due to the **immaturity** of the **hypothalamic–pituitary–ovarian axis**.
99
The _____ controls anterior pituitary functions via the secretion of releasing and inhibiting factors.
The **_hypothalamus_** controls anterior pituitary functions via the secretion of releasing and inhibiting factors.
100
The hypothalamus initially releases gonadotropin-releasing hormone (GnRH) in a pulsatile manner. On average, the frequency of GnRH secretion is once per _____ minutes during the early follicular phase, increases to once per _____ minutes during the middle of the menstrual cycle, and then decreases during the luteal phase.
The hypothalamus initially releases gonadotropin-releasing hormone (GnRH) in a pulsatile manner. On average, the frequency of GnRH secretion is once per **_60 to 100_** minutes during the early follicular phase, increases to once per **_60 to 70_** minutes during the middle of the menstrual cycle, and then decreases during the luteal phase.
101
Oval-shaped, pea-sized pituitary gland that is located in a small depression in the sphenoid bone of the skull.
Pituitary gland
102
What 7 hormones does the anterior pituitary gland synthesize?
1. Growth hormone (GH)
2. Thyroid-stimulating hormone (TSH)
3. Adrenocorticotropin (ACTH)
4. Melanocyte-stimulating hormone (MSH)
5. Prolactin (PRL)
6. Follicle-stimulating hormone (FSH)
7. Luteinizing hormone (LH)
103
T/F The endometrium emulates the activities of the ovaries; thus whatever happens in the uterus during the menstrual cycle is precisely correlated with whatever is occurring in the ovaries.
True
104
What are the objectives of the ovarian and endometrial cycles?
1. Ovarian: Produce an ovum.
2. Endometrial: Prepare a site to nourish and maintain the ovum if it becomes fertilized.
105
What are the phases of the ovarian cycle?
1. Follicular phase
2. Ovulatory phase
3. Luteal phase
106
What are the 3 phases of the endometrial cycle?
1. Proliferative phase
2. Secretory phase
3. Menstruation
107
Almost all hormones are released in short pulses at intervals of _____ to _____ minutes throughout most of the menstrual cycle, with these pulses decreasing in frequency closer to menstruation. _____ hormones modulate the frequency and amplitude of the pulse, which varies throughout the cycle.
Almost all hormones are released in short pulses at intervals of **_60**_ to _**90**_ minutes throughout most of the menstrual cycle, with these pulses decreasing in frequency closer to menstruation. _**Steroid_** hormones modulate the frequency and amplitude of the pulse, which varies throughout the cycle.
108
T/F Although the presence of progesterone reduces the frequency of the hypothalamic GnRH pulses, the amount of LH released from the pituitary is proportionally increased to sustain the corpus luteum and the production of progesterone.
True
109
What happens in the menstrual cycle in the absence of pregnancy?
The corpus luteum degenerates, progesterone levels decline, and menstruation occurs.
110
When does folliculogensis begin and end?
During the **last few days of the previous menstrual cycle** and continues until the **release of the mature follicle at ovulation**.
111
When are a cohort of primary follicles recruited?
**Days 1-4** of menstrual cycle.
112
Follicles that have enough _____ cells will develop receptors for estrogen and FSH on the cells of the granulosa layers, and LH receptors on the theca cells.
Follicles that have enough **_granulosa_** cells will develop receptors for estrogen and FSH on the cells of the granulosa layers, and LH receptors on the theca cells.
113
What is the primary role of FSH?
Induce the development of increased receptors on the granulosa cells and thereby stimulate estrogen production.
114
What is the preliminary role of LH?
Stimulate the cells’ production of androgen that will be converted to estrogen by the granulosa layers.
115
When is one dominant follicle from the cohort of recruited follicles chosen to ovulate during the next menstrual cycle?
Days 5-7
116
Dominant follicle.
Graafian follicle
117
Contains the ovum and is surrounded by a layer of granulosa cells, which are themselves surrounded by the specialized theca interna and theca externa cells.
Graafian follicle
118
What happens to the oocyte at ovulation?
1. Initially the nuclear membrane around the oocyte breaks down.
2. The chromosomes progress through the rest of the first meiotic division.
3. The egg moves on to the secondary stage.
4. Meiosis ceases at this time and will be initiated again only if the ovum is fertilized.
119
When does the LH surge occur for more than 2/3 of women?
Around 3 a.m.
120
When does ovulation primarily occur?
1. Morning during the spring months.
2. Evening during autumn and winter.
3. In the Northern Hemisphere, from July to February, approximately 90% of women will ovulate between 4 and 7 p.m.
4. During the spring, 50% of women will ovulate between midnight and 11 a.m.
121
How long does the corpus luteum function after ovulation?
Approximately **8 days**
122
What does the corpus luteum become?
Corpus albicans
123
They occur in preparation for implantation of the fertilized ovum.
Progressive mitotic growth of the deciduas functionalis in response to increasing levels of estrogen secreted by the ovary.
124
T/F Menstruation results from vascular events.
False. The current theory suggests that menstruation is initiated by enzymatic autodigestion of the functional layer of the endometrium, which is triggered by estrogen–progesterone withdrawal. As estrogen and progesterone levels fall during the days prior to menses, lysosomal membranes become destabilized, such that the enzymes within them are released into the cytoplasm of the epithelial, stromal, and endothelial cells and into the intercellular space. These enzymes are proteolytic: They digest the cells surrounding them as well as surface membranes. Their actions result in platelet deposition, release of prostaglandins, vascular thrombosis, extravasation of red blood cells, and tissue necrosis in the vascular endothelium. Enzymatic action progressively degrades the endometrium and eventually disrupts the capillaries and venous system just under the endometrial surface, causing interstitial hemorrhage and dissolution of the surface membrane and allowing blood to escape into the endometrial cavity. This degeneration continues and extends to the functional layer of the endometrium, where rupture of the basal arterioles contributes to the bleeding.
125
\_\_\_\_\_ initiate contractions of the uterine smooth muscle and sloughing of the degraded endometrial tissue, leading to menstruation.
**_Prostaglandins_** initiate contractions of the uterine smooth muscle and sloughing of the degraded endometrial tissue, leading to menstruation.
126
What is menstrual fluid made of (4 things)?
1. desquamated endometrial tissue
2. red blood cells
3. inflammatory exudates
4. proteolytic enzymes
127
When is cervical mucus scant and viscous?
After menstruation
128
In late follicular phase, the quantity of cervical mucus increases _____ compared to the early follicular phase and can stretch to at least \_\_\_\_\_.
In late follicular phase, the quantity of cervical mucus increases **_30-fold**_ compared to the early follicular phase and can stretch to at least _**6 cm_**.
129
What helps reduce infection risk at the time of possible implantation?
* After ovulation, when progesterone levels are high, the cervical mucus once again becomes thick, viscous, opaque, and decreased in amount.
* This thick mucus is hostile and impenetrable to the sperm.
* The increased viscosity also reduces the risk of ascending infection at the time of possible implantation.
130
What happens to the cervix around ovulation?
1. The cervix becomes **softer** a few days prior and at ovulation.
2. The external cervical os **everts** prior to ovulation.
131
T/F Menstrual blood contains clots.
False. Because some of the clotting factors ordinarily found in blood are lysed by lysosomal enzymes in the uterus, **menstrual blood does not clot.**
