1 Flashcards
(154 cards)
1
Q
List the 2 advantages of breast milk for the mother
A
- The release of oxytocin, which increases the speed of uterine involution & the suppression of the menstrual cycle
2
Q
List the advantages of breast milk for the development of the baby when compared to other sources of nutrition such as formula
(hint: 4 advantages)
A
- Better digestion & absorption of fats, iron, & amino acids
- Improved immunity
- Development of digestive system bacteria
- Decreased risk of diseases later in life
3
Q
When does breast milk increase in nutrient content, mineral content, growth factors, hormones, & antibodies?
& what is included in the nutrient & mineral contents?
A
- After approximately the first 5 days
- Nutrient content includes: Triglyceride fat, lactose, proteins, & vitamins
- Mineral content includes: Calcium & phosphate
4
Q
What is a dilute fluid that contains low concentrations of fat & lactose but high concentrations of immunoprotective factors?
A
- Colostrum, & is the 1st breast milk produced after the birth of the baby
5
Q
What is the reflex called that induces lactation?
And, describe the events that it instigates & the hormones it releases
A
- Sucking of the baby (sucking reflex)
- Which instigates a series of events leading to the release of prolactin & oxytocin from the pituitary to induce lactation
6
Q
During pregnancy, the mammary glands are developed due to the actions of which hormones?
Simultaneously, lactation is inhibited by the actions of which hormones?
And, when is this inhibition removed?
A
- Developed due to the actions of estrogens, progesterone, & human placental lactogen (hPL)
- Lactation is inhibited by the actions of estrogen, & progesterone & this inhibition is removed at parturition (the act of giving birth)
7
Q
What is uterine involution?
When does it occur?
And, which type of females experience faster uterine involution?
A
- Uterine involution, is the return of the uterus to its pregestational size (before pregnancy)
- It occurs during that same time frame in response to decreased concentrations of estrogens & progesterone
- Females who breastfeed have increased concentrations of oxytocin, thus experiencing faster uterine involution.
8
Q
Following parturition, any remaining endometrial tissue is sloughed off in a vaginal discharge called?
And, how long may it continue for following parturition?
A
- Lochia, which may continue for up to six weeks following parturition
9
Q
What is the hormone called that binds to the uterine oxytocin receptors & stimulates contraction of the uterus?
How is it part of a positive feedback loop?
And what else does it stimulate to further the contractions of the uterus? (hint: placenta
A
- The posterior pituitary hormone oxytocin
- This is part of a positive feedback loop because the contractions push the uterine contents against the cervix, stretching the cervix, which results in the secretion of more oxytocin from the posterior pituitary
- Oxytocin also stimulates the placenta to secrete prostaglandins, which further stimulate the contraction of the uterus
10
Q
Since Dehydroepiandrosterone (DHEA) is converted by the placenta into estrogen, where does that estrogen enter?
And, what does it stimulate & induce?
A
- This estrogen enters the maternal plasma & stimulates the development of gap junctions in the myometrium,
- & induces the expression of oxytocin receptors in the uterus.
11
Q
What does the placental corticotrophin-releasing hormone (CRH) stimulate the secretion of?
And, what does that hormone stimulate the production of? (which 2 hormones)
& there functions
A
- CRH stimulates the secretion of fetal adrenal corticotrophin hormone (ACTH)
- ACTH:
Stimulates the production of fetal cortisol, which is important for fetal lung maturation,& of dehydroepiandrosterone (DHEA), which is converted by the placenta into estrogen
12
Q
Which 2 things increase cytokine & prostaglandin production, triggering an inflammatory response relating to parturition?
And, what does that inflammatory response result in? (the secretion of…)
A
- An increase in uterine stretch (due to the growing size of the fetus) & the presence of pulmonary surfactant in the amniotic fluid (due to the maturation of the fetal lungs)
- Results in the secretion of placental corticotrophin-releasing hormone (CRH)
13
Q
What is controlled by a complex series of events involving the uterus, the placenta, the developing fetus, the maternal plasma, & the endocrine system?
A
- The timing of parturition
14
Q
Summarize the events or 3 stages of parturition
A
- 1st stage: Is characterized by cervical dilation and uterine contractions (labour). Uterine contractions: Begin at the superior (upper) surface of the uterus and travel downward toward the cervix. These contractions are coordinated by gap junctions throughout the myometrium. Each contraction pushes the uterine contents against the cervix, slowly wedging it open.
- 2nd stage of labour: The maximal dilation of the cervical canal allows for the baby to move through the birth canal. Voluntary & involuntary contractions of the abdominal muscles facilitate this process.
- 3rd stage of labour: Is the delivery of the placenta, which is accomplished by uterine contractions shortly after the birth of the baby.
15
Q
What is the event that signals the beginning of parturition?
A
- The rupturing of the amniotic sac
16
Q
What is it called when the fetus does not position itself with its head against the cervix?
A
- A breech birth
17
Q
Describe the significance of cervical ripening & fetal positioning prior to parturition
A
- Cervical ripening also occurs prior to parturition, where the cervix begins the process of ripening in which the collagen fibres in the connective tissue of the cervix begin to be broken down
- And the fetus positions itself with its head in contact with the cervix
18
Q
Why does uterine contractile activity increase prior to parturition?
And what are premature uterine contractions called?
A
- It increases because the plasma concentrations of estrogen exceed those of progesterone & because uterine smooth muscle stretch receptors respond to the increased size of the fetus.
- Braxton-Hicks contractions
19
Q
How long is a full-term pregnancy from the date of the last menstrual period (LMP)?
A
- It is 38 weeks in length or 40 weeks from the date of the last menstrual period (LMP).
20
Q
What is the process of birth called?
A
- Parturition
21
Q
(Maternal effects of pregnancy) Which 2 hormones secreted by the placenta play an important role in altering maternal metabolism?
And, what are their functions?
A
- Human placental lactogen (hPL) or human chorionic somatomammotropin (hCS): Which Promotes a maternal glucose-sparing effect, thereby ensuring that the fetus receives an adequate supply of glucose for energy production. It also promotes the growth of the fetus & stimulates maternal breast maturation
- Parathyroid hormone-related peptide (PTHrp): Which mobilizes calcium from maternal bones, thereby ensuring that the fetus receives an adequate supply of calcium for growth.
22
Q
(Maternal effects of pregnancy) What is the 1st physiological change that occurs during pregnancy?
When and why does this physiological change happen (which hormones are it attributed to)?
What other body systems experience physiological changes, as a result, to accommodate the additional demands of the fetus?
A
- The 1st change is often morning sickness.
- This bout of nausea, which can occur at any time of the day, and is attributed to increased concentrations of human chorionic gonadotropin (hCG), estrogens, & progesterone.
- The activities of the urinary, respiratory, & cardiovascular systems all increase to accommodate the additional demands of the fetus.
23
Q
(Maternal effects of pregnancy) What is 1st anatomical change that occurs during pregnancy?
And, what anatomical changes does the uterus experience?
(Hint: Eventually, the weight of the uterus increases to…)
A
- 1st anatomical change is the enlargement of the breasts & the darkening of the areolaes
- The uterus begins to expand with the growing fetus & comes to occupy the majority of the abdominal cavity
- Eventually, the weight of the uterus increases to more than 20 times its original weight. This increase is largely due to the presence of a growing fetus but is also due to uterine growth.
24
Q
What do the maternal effects of pregnancy include?
A
- Includes: Anatomical, physiological, & metabolic changes
25
(Maintenance of pregnancy) When & how does the placenta convert cholesterol to progesterone & convert dehydroepiandrosterone (DHEA) to estrogen for secretions?
- The placenta has enzymes required to convert cholesterol into progesterone not long after implantation, but it takes 10 weeks for the placenta to become large enough to provide sufficient progesterone to meet the needs of the endometrium
- Similarly, it converts the androgen dehydroepiandrosterone (DHEA) to estrogen for secretion, but it depends on the slowly developing fetal adrenal cortex to produce DHEA.
26
(Maintenance of pregnancy) What are the structures called that secrete estrogen & progesterone?
And, for which periods do they take over during pregnancy?
- Corpus luteum: Secretes these hormones for the initial 2 months of pregnancy
- Placenta: Takes over the secretion of these hormones for the rest of pregnancy (2-9 months)
27
(Maintenance of pregnancy) What is the human chorionic gonadotropin (hCG) secreted by?
Why are its secretions important?
And, what is the hormone detected in a urine pregnancy test?
- Is secreted by the chorionic cells of the developing embryo, & is important for maintaining the corpus luteum
- hCG
28
List the key hormones that play a primary role in the maintenance of pregnancy
- Human chorionic gonadotropin (hCG), estrogen, & progesterone
29
List the functions of the placenta (all 3)
- It provides a protective barrier for the developing embryo, separating the maternal blood from the blood of the developing embryo
- It takes over the roles of the digestive, respiratory, & urinary systems
- & serves as an important endocrine gland for the duration of the pregnancy
30
(Placentation)
Describe the entry and exit of maternal & fetal blood (capillaries), regarding the placenta.
And, how the fetal blood leaves the placenta. (Fetal placental capillaries & how fetal blood leaves the placenta)
- Maternal blood enters the placenta: Through the maternal arterioles & moves through a pool of blood in the intervillus spaces
- Maternal blood leaves the placenta: Through the maternal venules
- Fetal placental capillaries: Branch off the umbilical artery & project into the placental villi where exchanges are made between the fetal & maternal blood
- Fetal blood leaves the placenta: Through the umbilical vein
31
(Placenta development) What occurs after 9 weeks of prenatal development?
And, what is that embryo then referred to as?
- All the essential internal & external structures are present in the embryo
- Embryo is referred to as a fetus
32
(Placenta development) The outer layer of trophoblast cells divides and develops into the....?
Where does it project, and what does it form?
And, what forms within the inner cell mass?
- The Chorion cells, which project into the blood-filled cavities of the endometrium & form the chorionic villi of the placenta
- Additionally, a fluid-filled amniotic cavity forms within the inner cell mass
33
(Processes of implantation) What is the blastocyst referred to as upon successful implantation?
- Embryo
34
What is it called when implantation occurs in a location other than the uterine cavity?
- Ectopic pregnancy
35
(Processes of implantation) What do trophoblast cells of the blastocyte also secrete to initiate the decidual response?
And, what is the decidual response?
- Also, secrete paracrines, which initiate the decidual response,
- Decidual response is a set of changes (e.g., vascularization) in the endometrial tissue
36
(Processes of implantation)
What is the physiological significance of the enzymes secreted by the trophoblast cells of the blastocyst?
- Trophoblast cells secrete enzymes that digest the endometrial cell layer to provide a physical space for the blastocyst to embed itself
- The digestion & breakdown of the endometrial tissue by the trophoblasts provides nutrients for the dividing cells of the blastocyst
37
(Processes of implantation) What results from the actions of the trophoblast cells?
- Implantation
38
(Processes of implantation) What occurs following the movement of the blastocyst into the uterine cavity?
- Implantation usually occurs
39
(Processes of fertilization) What do the outer & inner layers of the blastocyst cells become?
And describe the significance of said layers
- Outer layer = trophoblast, which is a layer of cells important both for implantation & for the development of the fetal placenta
- Inner layer = inner cell mass, which will develop into the embryo
40
(Processes of fertilization) What are the cells called that are not differentiated in any way from one another, and each has the ability to develop into a separate embryo?
What occurs if the division of the morula occurs?
And, with continued cell division, the totipotent cells of the morula begin to differentiate & form a...?
- Totipotent cells
- Identical or monozygotic twins will be produced
- Forming a blastocyst
41
(Processes of fertilization) What occurs over the next three to four days to the zygote following sperm-oocyte fusion? (hint: mitotic division...)
- The zygote mitotically divides to form a morula, which consists of totipotent cells
42
(Processes of fertilization) What is a fertilized ovum called?
And what is the sequence of events that occurs within the 1st hour of the sperm-oocyte fusion? (hint: The sperm plasma membrane...)
- Zygote
- The sperm plasma membrane disintegrates, the chromosomes from both the spermatozoon & the ovum migrate to the centre of the zygote, & the DNA is replicated in preparation for the 1st mitotic division
43
(Processes of fertilization) What must a spermatozoon do to be transported into the oocyte cytoplasm?
What does the sperm-oocyte fusion process trigger?
What does it prevent as a result?
Also stimulates the...
- Must be the 1st spermatozoon that successfully fuses with the oocyte
- It triggers the inactivation of sperm-binding proteins & the hardening of the zona pellucida, both of which prevent polyspermy (fertilization by more than one spermatozoon).
- Sperm-oocyte fusion stimulates the 2nd meiotic division of the oocyte to produce an ovum
44
(Processes of fertilization) What do oocytes release to facilitate the process of fertilization?
What does that chemical messenger stimulate?
How does the process of penetration through the corona radiata & zona pellucida begin?
And, what must the spermatozoa do to be able to fuse with the oocyte plasma membrane?
- Oocytes release a chemical messenger called allurin, which stimulates spermatozoa to move toward the oocyte
- Several sperm usually reach the oocyte & release their acrosomal enzymes to begin the process of penetration...
- Spermatozoa must also bind to sperm-binding proteins in the zona pellucida before being able to fuse...
45
What is the number of sperm that is deposited in the vagina? How many successfully arrive at the oocyte?
How long does the oocyte remain viable for following ovulation?
And, how long are spermatozoa able to survive in the female reproductive tract?
- Millions of sperm are deposited in the vagina, however only a few hundred successfully arrive at the oocyte
- Oocyte: Remains viable for only 12 to 24 hours following ovulation
- Spermatozoa: Survive for up to five days in the female reproductive tract
46
What is the process called that increases spermatozoan motility & is characterized by a set of functional changes occurring over a period of hours after the arrival of the spermatozoa in the female reproductive tract?
And, what is the purpose of the changes this process triggers to the plasma membrane of the spermatozoa?
- Process of capacitation
| - To help prepare the spermatozoa for fusion with the oocyte plasma membrane
47
What does the sperm movement through the cervical canal, uterus, & uterine depend on?
- Depends on the contractile activity of the smooth muscle of these structures & the motility of the spermatozoa.
48
As ovulation approaches, what occurs to the cervical mucus?
Also, what occurs around the time of ovulation?
- The cervical mucus becomes more profuse & less viscous,
| - Eventually becoming penetrable by sperm for a short period of a few days around the time of ovulation.
49
In the initial stages of pregnancy, where does fertilization occur in?
Also, upon deposition in the vagina, where must the spermatozoa travel through to reach the oocyte?
- Fertilization usually occurs in the uterine tubes
| - Spermatozoa must travel through the female reproductive tract
50
What do the initial stages of pregnancy consist of?
- Fertilization, implantation, & placentation
51
What is not involved in the maintenance of homeostasis but is important for the continuation of the species?
- The reproductive system
52
In females, what signals the end of their fertile period?
And, what are the symptoms or effects of said event?
- Menopause
- Ovulation ceases, estrogen levels decrease, & maintenance of the secondary sex characteristics & reproductive structures is discontinued.
53
What causes males to remain fertile their entire life?
- Due to plasma testosterone concentrations that may decrease slightly with aging, but remain in concentrations sufficient for continued spermatogenesis
54
Throughout which period of life are plasma concentrations of reproductive hormones typically remained high & are responsible for the maintenance of the reproductive organs & the secondary sex characteristics ?
- Throughout early adulthood (approximately ages 18 to 39)
55
Full reproductive maturity (fertility) is achieved by the end of which period of life?
- Puberty
56
During puberty, an increased concentration of which hormones in males & females are responsible for the development of the secondary sex characteristics?
- Testosterone & estrogen
57
Which period of life are the levels of reproductive hormones in both males & females are low ?
- Throughout childhood
58
What accounts for the decrease in estrogen & progesterone concentrations at the end of the luteal phase?
And what is responsible for triggering menstruation & the start of a new menstrual cycle? (The removal of what...)
- The degeneration of the corpus luteum
- The removal of the negative feedback (the inhibitory effects of estrogen & progesterone), which causes a small increase in FSH & LH levels
59
Following ovulation, in particular, the progesterone secreted from the newly formed corpus luteum is important for what exactly?
(hint: maintaining & developing ....)
- Is important in maintaining the secretory-phase conditions of the uterus & the development of the breasts
60
Following ovulation, what takes over the secretion of estrogen & progesterone?
What do estrogen & progesterone act on?
And why do they act on said structures?
(hint: which 2 structures & to decrease what)
- The newly formed corpus luteum
| - Both estrogen & progesterone act on the hypothalamus & anterior pituitary to decrease the secretion of FSH & LH
61
What occurs with the expression of LH receptors on the granulosa cells?
And, how is it exerted in the late follicular phase?
This is called the _____, and is the primary factor in stimulating ___,____, & ___ of the ___ into the ___ ____
- With the expression of LH receptors on the granulosa cells, the granulosa cells become directly responsive to LH & secrete estrogen, which, in the late follicular phase, exerts positive feedback on the hypothalamus & anterior pituitary to increase the secretion of LH.
- This is called the LH surge, and is the primary factor in stimulating Meiosis I, ovulation, and transformation of the follicle into the corpus luteum.
62
During the mid-follicular phase, what are the physiological roles of the estrogen that is secreted by the granulosa cells?
(hint: What does it maintain & induce..)
- It is responsible for maintaining the accessory reproductive organs & secondary sex characteristics,
- for maintaining the proliferative-phase uterine changes,
- & for inducing the expression of LH receptors on granulosa cells & of progesterone receptors in the uterus
63
During the mid-follicular phase, estrogen secretion acts on what?
Why does it act on said structures?
(hint: It decreases ...)
- Unlike inhibin, estrogen acts on both the hypothalamus & anterior pituitary to decrease the secretion of gonadotropin-releasing hormone (GnRH), follicle-stimulating hormone (FSH), & luteinizing hormone (LH).
64
During the mid-follicular phase, inhibin secretion by granulosa cells acts on what?
And, why does it act on said structure?
- Acts on the anterior pituitary to decrease follicular-stimulating hormone (FSH) secretion only
65
During the mid-follicular phase, what do estrogen & the follicle-stimulating hormone (FSH) stimulate?
- Stimulate oogenesis & follicular development
66
Describe the events that occur during the mid-follicular phase, regarding estrogen.
High levels of estrogen are secreted from ____ in response to ___
(hint: thecal cells)
- High levels of estrogen are secreted from the follicular cells in response to LH
- While the thecal cells secrete androgens that are subsequently converted into estrogen by the granulosa cells
67
In the menstrual cycle, the follicle-stimulating hormone (FSH) & luteinizing hormones (LH) both play a role in regulating the secretion of ____ & ____
- Both play a role in regulating the secretion of estrogen & progesterone
68
In the menstrual cycle, the ______ is responsible for the secretion of the gonadotropin-releasing hormone (GnRH), which acts on the anterior pituitary to increase the secretion of follicle-stimulating hormone (FSH) & luteinizing hormone (LH)
- The hypothalamus
69
How are the events of the menstrual cycle regulated?
- They are hormonally regulated
70
In the uterine cycle, the secretory phase is regulated by____ secreted from the ____ ____
- By progesterone secreted from the corpus luteum
71
In the uterine cycle, describe the events that take place in the secretory phase
- The uterus prepares itself for the implantation of a fertilized oocyte
- The blood supply to the uterus is increased, the endometrial glands actively secrete glycogen-rich fluid, & cervical secretions become viscous to form a cervical plug
72
In the uterine cycle, when does the secretory phase (progestational phase) begin & end?
- Begins with ovulation & ends with the onset of menstruation
73
In the uterine cycle, the proliferative phase is regulated by? And, where is that hormone secreted?
- By estrogen secreted from the follicular cells
74
In the uterine cycle, describe the events that take place in the proliferative phase
(hint: endometrial ...)
- The uterus begins to restore itself to its pre-menstruation state in preparation for the fertilization of the oocyte
- The endometrial layer begins to grow, endometrial glands develop, & the cervical glands secrete mucus
75
In the uterine cycle, when does the proliferative phase (proliferation phase) begin & last?
- Begins with the end of menstruation & lasts until ovulation
76
In the uterine cycle, what is the menstrual phase triggered by?
- By a decrease in the concentrations of estrogen & progesterone secreted by the degenerating corpus luteum
77
In the uterine cycle, what occurs & results in the menstrual phase?
- The shedding of the uterine lining occurs in response to a decrease in the blood supply to the uterus
- As a result, the uterine tissue cells die & are sloughed off into the vagina (period)
78
In the uterine cycle, how long does the menstrual phase last?
- Lasts for the period of menstruation (approximately five days, but sometimes lasting up to seven days).
79
What are the divisions of the uterine cycle called?
And, which phases do they overlap in the ovarian cycle?
- The menstrual, proliferative, & secretory phases
- The menstrual & proliferative phases: Overlap with the follicular phase of the ovarian cycle
- The secretory phase: Overlaps with the luteal phase of the ovarian cycle
80
Study the Ovarian cycle, including the follicular and luteal phases for approx 5 to 10 mins right now! (p.g 51 in word docx)
- Studied
81
What are the divisions of the ovarian cycle called?
And, when do they individually begin & end?
- The follicular phase, which begins with the onset of menstruation & ends with ovulation
- The luteal phase, which begins with ovulation & ends prior to menstruation
82
How can the menstrual cycle be described?
- Described in terms of the events that occur in the ovary (ovarian cycle) & the events that occur in the uterus (uterine cycle).
83
The female reproductive activity involves ___ ___.
And, how is it governed?
- It involves cyclical changes that are governed by the menstrual cycle
84
How is the regulation of the female reproductive function different than the regulation in the male reproductive system?
- It is more complex than in the male reproductive system
85
Describe the events in oogenesis
| hint: During fetal development...
- During fetal development, diploid oogonia undergo mitosis & differentiate into primary oocytes
- The primary oocytes remain unchanged in a period of the meiotic arrest until the pubertal stage of development is complete
- Individual primary oocytes will complete Meiosis I prior to ovulation & will continue to complete Meiosis II following fertilization
- These meiotic divisions produce one haploid ovum post-fertilization & two polar bodies that lack cytoplasm & intracellular organelles
86
What are diploid, undifferentiated germ cells that undergo mitosis in the first three months of prenatal development?
- Oogonia
87
How is the number of oogonia (in females) different from spermatogonia (in males)?
- The # of oogonia is determined prior to birth & limits the period of fertility within the female lifespan
88
What is the gamete production in the female called?
Where does it occur?
And, when does it begin?
- Called oogenesis
- Occuring in the ovary
- & begins prior to birth
89
What is the term called that refers to the area that includes the external genitalia & the urethral & anal openings?
- The perineum
90
In females, what does the external genitalia consist of?
And, provide a brief description of each structure
- Labium majora, which are the outer skin folds
- Labium minora, which are the inner skin folds
- Clitoris, which is the female erectile organ
91
What does the vaginal wall consist of?
And, what is the function of secretions in the said wall?
- It contains smooth muscle & is bathed in the acidic secretions by the cervical glands
- These secretions help to protect against bacterial infection
92
What is the female organ of copulation (sexual intercourse) called?
- The vagina
93
Name the 3 cellular layers that make up the uterine (uterus) wall.
And, what are they each composed of?
The perimetrium – Is composed of epithelial cells & connective tissue
The myometrium – Is composed of smooth muscle
The endometrium - Is composed of epithelial cells, glandular cells, & connective tissue.
94
The cervix & vagina both compose the ___ ____
- The birth canal
95
What are the 2 divisions of the uterus called? And, describe their location
- The body, which is the upper portion
| - The cervix, which is the lower portion leading into the vagina
96
What is the site of fetal development?
- The uterus
97
What is also the site for fertilization & leads into the uterus?
- The uterine tubes or fallopian tubes
98
What are responsible for the movement of both fluid & the oocyte toward the uterus?
- The peristaltic contractions & the ciliary actions of the epithelial cells lining the uterine tubes
99
What are the finger-like projections that extend from the uterine tubes & mark the entrance to the reproductive tract called?
- Fimbriae
100
What are the structure called that are responsible for the transport of oocytes (which are released from the ovary during ovulation) to the uterus?
- The uterine tubes, also known as Fallopian tubes or oviducts
101
Describe the function or role of the granulosa cells in relation to the maturation of oocytes
- They are analogous to those of the Sertoli cells of the testis.
- Granulosa cells provide nourishment to the oocytes through gap junctions,
- Are activated by follicle-stimulating hormone (FSH) & estrogen to stimulate follicular development.
- They also produce antral fluid, which is important for the maturation of the oocyte. & secrete the hormones estrogen & inhibin
102
In the ovaries, at birth, all follicles are?
And describe these follicles in relation to ovulation
- All follicles are primordial follicles in which the oocyte is surrounded by granulosa cells
- Primordial follicles must develop to maturity prior to ovulation
103
In the ovaries, what do each follicle contain?
- Each follicle contains one oocyte
104
What are the female gonads & the site of ova maturation called?
And, what are they composed of?
- The ovaries,
| - They are composed of connective tissue & follicles & are physically distinct structures from the reproductive tract
105
What does the female reproductive system anatomically consist of? (list the structures)
- The gonads (ovaries), reproductive tract (uterine tubules, uterus, & vagina), & external genitalia (vulva).
106
In males, after birth, list the effects that testosterone exerts
List all 7 effects
Testosterone promotes growth & maturation of the reproductive system at puberty
Testosterone maintains the reproductive system during adulthood
Testosterone stimulates spermatogenesis
Testosterone develops & maintains the sex drive
Testosterone develops & maintains the secondary sex characteristics, including the male pattern of hair growth, deepening of the voice, & muscle growth
Testosterone promotes protein anabolic effects
Testosterone promotes bone growth & closure of the epiphyseal plates during puberty
107
Why is testosterone critical prior to birth in males?
- Testosterone is critical for sexual differentiation & the masculinization of the reproductive tract & external genitalia,
- as well as for triggering the descent of the testes into the scrotum
108
What is the primary male androgen, that exerts numerous effects throughout the lifespan of the male?
- Testosterone
109
In the hormonal regulation of the male reproductive hormones, why does inhibin act in a negative feedback fashion?
- To inhibit the secretion of the follicle-stimulating hormone (FSH)
110
In the hormonal regulation of the male reproductive hormones, why does testosterone act in a negative feedback fashion?
- To inhibit the secretion of the follicle-stimulating hormone (FSH) & the luteinizing hormone (LH)
111
What regulated the secretion of the follicle-stimulating hormone (FSH) & the luteinizing hormone (LH)?
And, where is this hormone released from?
- By gonadotropin-releasing hormone (GnRH) released from the hypothalamus
112
What regulates the secretions of testosterone & spermatogenesis in males?
And, where are these hormones released from?
- By follicle-stimulating hormone (FSH) & luteinizing hormone (LH), both of which are released from the anterior pituitary gland
113
Describe the motility of spermatozoa in the seminiferous tubules, epididymis, & vas deferens
- Initially immotile when released into the seminiferous tubules & in the following weeks, are moved by peristaltic contractions into the epididymis, where they acquire their motility & the ability to carry out fertilization.
- Additional peristaltic contractions continue to move the spermatozoa into the vas deferens, where they remain until they are released during ejaculation.
114
What does the midpiece part of the spermatozoon consist of?
- Mitochondria: Which provides the energy required for the movement of the long tail
115
What does the head part of the spermatozoon consist of?
And describe each part
- Acrosome: which is a small, cap-like region of the head, contains the enzymes required for fertilization.
- Nucleus: A much larger, centrally located region of the head, that contains the chromosomes.
116
What is each individual sperm known as? And, what are the names of the 3 parts it consists of?
- Spermatozoon, consisting of 3 parts -- a head, a midpiece, & a tail
117
What is mature spermatozoa commonly referred to as?
- Sperm
118
Describe the process of spermatognesis
- Following the mitotic division of spermatogonia to produce primary spermatocytes. The primary spermatocytes move through the tight junction between neighbouring Sertoli cells of the blood-testes barrier to the luminal compartment
- In the luminal compartment, the primary spermatocyte undergoes the events of Meiosis I to form two secondary spermatocytes,
- Which then (assuming that all survive) undergo the events of Meiosis II to produce four haploid spermatids that will mature into spermatozoa before entering into the lumen of the seminiferous tubules
119
How do spermatogonia divide? What do they produce as a result of division?
And, why is this form of division significant for males?
- The spermatogonia mitotically divide to produce replacement spermatogonia & primary spermatocytes
- This mitotic division of the spermatogonia maintains a resident population that enables the male to remain fertile throughout his lifespan
120
What are the least developed germ cells, which are diploid, undifferentiated germ cells?
And, where are they located?
- Spermatogonia
| - located in the basolateral compartment between the Sertoli cells
121
What is the term called that refers to gamete production in males? Where does it occur?
Also, what is contained within the structure in which gamete production in males takes place?
- Spermatogenesis occurs in the seminiferous tubules
| - Seminiferous tubules contain both Sertoli cells & germ cells (which exist in various stages of development).
122
(male reproductive system) List the accessory glands & their corresponding secretions
- The seminal vesicles: Secrete a fluid enriched with fructose & prostaglandins
- The prostate gland: Secretes an alkaline fluid enriched with citrate & numerous enzymes.
- The bulbourethral glands: Secrete a fluid enriched with mucus
123
Why are the secretion of the accessory glands important?
- Important for copulation (sexual intercourse) & for the survival of the spermatozoa in the female reproductive tract
124
Describe the path of the spermatozoa in the reproductive tract from the efferent ductules to the urethra
- Efferent ductules empty into the epididymis & then into the vas deferens (ductus deferens), which merge with ducts from the seminal vesicles to form the ejaculatory duct.
- The ejaculatory duct then passes through the prostate gland, where it joins the urethra.
125
As the seminiferous tubules move the spermatozoa into the reproductive tract, where does it begin and where does it lead to?
- Begins with the rete testis
| - & leads into the efferent ductules
126
What does the external genitalia of males consist of? And, what is the function of said external structures?
- The penis, which is the male copulatory organ & is responsible for depositing spermatozoa into the female reproductive tract during copulation (sex)
- The scrotum, which the descent of the testes into the scrotum during prenatal development is an important process for male fertility, as spermatozoa need temperatures less than that of the body for development
127
What is the function of the outer layer of smooth muscle cells in the seminiferous tubules?
- These muscles mediate the peristaltic contractions required for the movement of the spermatozoa through the seminiferous tubules toward the reproductive tract
128
What other hormones and substances do Sertoli cells secrete? (2 in total) (hint: both inhibit)
And, what is the function of said secretions?
- Inhibin, which acts on the anterior pituitary to decrease the secretion of FSH
- Müllerian-inhibiting substance (MIS), which is secreted during embryonic development to facilitate male sexual differentiation
129
What are the roles of the Sertoli cells as mature spermatozoa are released into the lumen of the seminiferous tubules?
- They provide nourishment to the spermatozoa, secreting luminal fluid & androgen-binding protein
- And form the blood-testes barrier
130
What are the epithelial cells making up the seminiferous tubules called?
What is these cells' function?
How & why are they activated?
- Sertoli cells, which support sperm development in a number of ways
- They are activated by testosterone & follicle-stimulating hormone (FSH) to stimulate spermatogenesis
131
What do the male gonads or testes consist of?
And, what are its functions?
- Consists of numerous seminiferous tubules, which function in sperm development
- Also consists of Leydig (interstitial) cells, which secrete testosterone
132
What does the male reproductive system anatomically consist of?
- The gonads (testes), the external genitalia (penis & scrotum), reproductive tract (vas deferens, ejaculatory duct, & urethra), & accessory glands (seminal vesicles, prostate gland, & bulbourethral gland).
133
Describe the events of sex differentiation
- If the testes develop, as a result of the presence of the Y chromosome, the testes secrete both testosterone, which stimulates the development of the Wolffian ducts, & Mullerian-inhibiting substance (MIS), which stimulates the degeneration of the Müllerian ducts
- In a zygote where the Y chromosome is absent, no testes develop &, in the absence of testosterone and Mullerian-inhibiting substance (MIS), Wolffian ducts degenerate & Mullerian ducts develop.
134
What are the 2 structures called that the embryo contains which are involved in sex differentiation? And, what are they a precursor to?
- The Wolffian ducts, which are the precursor to the male reproductive tract
- The Müllerian ducts, which are the precursor to the female reproductive tract
135
The sex differentiation or phenotypic sex is dependent on the secretions of the hormones _____ & _____ ____
- Upon the secretion of the hormones testosterone & Mullerian-inhibiting substance (MIS)
136
Describe the events of sex determination
- In a zygote with a Y chromosome, the presence of the sex-determining region on the Y (SRY) gene will result in the development of testes
137
What codes for the protein called H-Y antigen?
And, what occurs in the absence or presence of the H-Y antigen?
- The SRY gene
- In the presence of H-Y antigen: Testes will develop in the embryo during the seventh week of prenatal development.
- In the absence of H-Y antigen: Tests will not develop, & ovaries will develop by default during the ninth week of prenatal development.
138
What has a sex-determining region on the Y (SRY) gene
- The Y chromosome
139
What can supply the zygote with an X or a Y chromosome? Therefore, are responsible for determining the sex of the zygote
- The spermatozoa
140
What supplies the zygote with an X chromosome only?
- The ovum
141
What is sex determination or gonadal sex dependent on?
- Upon the sex chromosomes present in the zygote or fertilized ovum
142
What do the accessory reproductive organs include?
- The reproductive tracts & glands
143
What are the plasma concentrations of the reproductive hormones in males & females?
- In males: The plasma contains high concentrations of androgens and lower concentrations of estrogens & progesterone
- In females: The plasma contains high concentrations of estrogens & progesterone & lower concentrations of androgens
144
Where are the reproductive hormones also secreted from?
- From the adrenal cortex
145
What are the haploid cells produced in the meiotic divisions of gametogenesis from undifferentiated germ cells called?
And, what are they called in the male & female reproductive system?
- Gametes
- The gametes in the male: Are the spermatozoa
- The gametes in the female: Are the ova
146
What is the function of the gonads?
What are they called in the female and male reproductive systems?
And, what are the reproductive hormones secreted by the female & male gonads called?
- Function: In the production of gametes & reproductive sex hormones
- The gonads in the Male: Are the testes
- The gonads in the Females: Are the ovaries
- Secreted hormones in males: Androgens
- Secreted hormones in females: Estrogens (i.e., estradiol, estrone, & estriol) & progesterone
147
These organs involved in gametogenesis, mating, or the production of offspring include?
- The gonads & the accessory reproductive organs
148
The reproductive system consists of all the organs involved in _____,____,or____ __ ____
- Gametogenesis, mating, or the production of offspring
149
Describe the motility of spermatozoa in the seminiferous tubules, epididymis, & vas deferens
- Initially immotile when released into the seminiferous tubules & in the following weeks, are moved by peristaltic contractions into the epididymis, where they acquire their motility & the ability to carry out fertilization
- Additional peristaltic contractions continue to move the spermatozoa into the vas deferens, where they remain until they are released during ejaculation
150
Describe the motility of spermatozoa in the seminiferous tubules, epididymis, and vas deferns
- Initially immotile when released into the seminiferous tubules and in the following weeks, are moved by peristaltic contractions into the epididymis, where they acquire their motility and the ability to carry out fertilization.
- Additional peristaltic contractions continue to move the spermatozoa into the vas deferens, where they remain until they are released during ejaculation.
151
What regulates the secretions of testosterone & spermatogenesis in males?
And, where are these hormones released from?
- By follicle-stimulating hormone (FSH) & luteinizing hormone (LH), both of which are released from the anterior pituitary gland
152
Following parturition, any remaining endometrial tissue is sloughed off in a vaginal discharge called? And, how long may it continue for following parturition?
- Lochia, which may continue for up to six weeks following parturition
153
During pregnancy, the mammary glands are developed due to the actions of which hormones?
- Developed due to the actions of estrogens, progesterone, & human placental lactogen (hPL)
154
During pregnancy, the mammary glands are developed due to the actions of which hormones?
- Developed due to the actions of estrogen, progesterone, & human placental lactogen (hPL)
