Endo Final Flashcards
(107 cards)
1
Q
How many chromosomes are in the ovaries and testes
A
23
2
Q
What determines sex differences
A
gonads and the hormones secreted by these organs
3
Q
What do the gonads regulate
A
i. Functional development of reproductive tract
ii. Adult sex characteristics
iii. Adult male and female brain
4
Q
What are the two regions gonads are divided into
A
Cortical Region – outer region,
Medullary Region – inner region,
5
Q
What gene determines sex
A
male gene
6
Q
Describe Sex Determining Y Gene (SRYGene)
A
SRY proteins are turned on
ii. If the SRY gene is present the embryo will develop into a male
if not present, it will be female
7
Q
explain TDF (Testis Determining Factor)
A
Testis Determining Factor (TDF) is a protein encoded by the SRY gene (Sex-determining Region Y gene) located on the Y chromosome. It plays a critical role in initiating the development of the testes during the early stages of embryonic development, leading to the determination of male sex.
b. Interstitial cell produces testosterone. Testosterone is important in male reproductive tract development
c. Testosterone exposed to 5 α reductase converts testosterone
8
Q
What do Sustentacular cells produce
A
Androgen-Binding Protein
Inhibin
Growth Factors & Nutrients
9
Q
What does the Wolfian Ducts (SRY gene present) do
A
Wolffian ducts develop into the male internal reproductive structures, including the epididymis, vas deferens, and seminal vesicles. This development is driven by androgens produced by Leydig cells
10
Q
explain the wolfian sequence when sry is present for reproduction
A
Ducts in the body that become the male organs, kickstarted by hormones. in females, they regress.
SRYà produce TDFà Embryonic Testesà Sustentacular Cells – MIF: degenerate female reproductive system
11
Q
What do nterstitial Cells (Leydig Cells produce
A
testerone
12
Q
What is Dihydrotestosterone
A
More potent form of testosterone; responsible for male external genitalia development and secondary sexual characteristics like facial hair and prostate growth.
Formed from testosterone via the enzyme 5α-reductase.
13
Q
What is Gynecomastia
A
Benign enlargement of male breast tissue, often due to hormone imbalance (increased estrogen or decreased androgens).
Puberty, obesity, liver disease, medications (e.g., spironolactone, ketoconazole, anabolic steroids), or hormonal tumors.
14
Q
Explain Mullerian Duct (SRY gene absent)
A
No SRYà so no MIFàmale wolfian ducts deteriorate
15
Q
Explain blood testees barrier
A
a. Created by tight junctions between Sertoli (sustentacular) cells
➤The blood-testis barrier is a physical and immunological barrier found in the seminiferous tubules of the testes. It is essential for proper spermatogenesis (the production of sperm) and for protecting developing sperm cells from harmful substances and the body’s immune system.
15
Q
what are the four things sertoli cells do?
A
- Involved in Sperm Maturation:
a. Provide nutrients and structural support to developing sperm cells (spermatogonia → spermatozoa).
b. Secrete androgen-binding protein (ABP) to maintain high testosterone levels locally, which is essential for spermatogenesis.
c. Form the blood-testis barrier, protecting developing sperm from immune system attack and toxins.
16
Q
What are the fsh effects on sertoli cells
A
a. Stimulates the production of androgen-binding protein (ABP)
➤ ABP binds testosterone and concentrates it in the seminiferous tubules, which is essential for spermatogenesis.
17
Q
Explain inhibin production
A
a. Produced by Sertoli (sustentacular) cells in response to FSH stimulation
➤ Function: Inhibin inhibits FSH secretion from the anterior pituitary through negative feedback, helping regulate the rate of spermatogenesis.
17
Q
explain interstitial cells
A
a. Produce testosterone in response to LH (luteinizing hormone) stimulation
➤ Function: Testosterone supports spermatogenesis (via Sertoli cells), and is responsible for the development of male secondary sexual characteristics (e.g., muscle growth, deep voice, facial hair).
18
Q
explain the hormones males secrete
A
continuous secretion of GNRH (hypothalamus), FSH, LH (ant. pituitary)
19
Q
Explain the hormones females secrete
A
cyclical production of GNRH (hypothalamus), FSH, LH (ant. pituitary)
b. Factors to turn on switch for puberty
20
Q
what controls gonadotropins
A
hypothalamus preoptic area
21
Q
What are the effects of testerone on the hypothalamus
A
–during neonatal period the hypothalamus is sensitized providing continuous secretion of GNRH for male reproduction.
22
Q
What is Testosterone effect on preoptic Area of Hypothalamus
A
increase in size and number of the cells in the preoptic nucleus.
23
explain the Maturation and Endocrine Development of the Female Brain
E2 regulates masculinization of the male brain. Why not the female brain?
i. Estradiol levels are low during the prenatal desensitization period.
ii. FEBP – Fetoneonatal estrogen binding protein
24
what inhibits inhibin
fsh
25
what is the semanal volume in the prostate gland
1/3 seminal volume
26
what is the semanal volume in the seminal vesicles
60%
27
what is Epididymus
continuation of sperm maturation
28
what are the anabolic effects of testerone on the male body
increase growth of muscle mass tissue increase hair growth, deepening of voice, increase muscularity.
29
explain synthetic androgens
Negative Feedback Mechanism – give exogenous testosterone will decrease GNRH, LH, FSH production – DHT 2 ½ more times more potent than testosterone need 5 α dehydrogenase.
b. Testosterone Receptor Binding.
c. Secondary Sex Characteristics – facial hair, muscle growth, thicker skin
30
What are the functions of the ovaries
Produce gametes
b. Make hormones
31
What is Oogenesis
This the process by which female gametes are produced in the ovaries. Unlike in males, the primary oocyte are produced during fetal development:
31
what are the types of tissue found in the female reporductive system
Epithelial Tissue: provides support
b. Mesenchymal Tissue: produces estrogen
32
What are Ovarian Follicle
An ovarian follicle is a fluid filled structure that consists of the developing oocyte as well as other cells involved in the maturation process.
33
What is Menarche
The first occurrence of menstruation in a female, marking the onset of puberty.
Occurs typically between ages 9-16, signaling the transition from childhood to reproductive capability.
The onset of menarche is influenced by genetics, health, and nutrition.
33
How many follicules do you have at birth vs at puberty
Birth: 2 million
Puberty:400,000
34
Describe menopause
The natural biological process marking the end of a woman's menstrual cycles, typically around age 50.
Defined as having gone 12 consecutive months without menstruation.
It occurs due to the depletion of ovarian follicles, leading to reduced estrogen and progesterone production.
Symptoms can include hot flashes, night sweats, mood changes, and vaginal dryness.
35
How many eggs ovulate in a life time?
400-500
36
What are the two types of cells that make up the ovarian follicle
Thecal Cells – develop from Mesenchymal Tissue, ovarian stomal cells, produce testosterone
ii. Theca Interna-
Secrete androgens, converted to estrogens via aromatase
37
explain the Theca Externa
1) Thecal Vascularization – thecal cells produce angiogenin (increase in blood flow and supply to developing follicle, after ovulation stays in ovary
2) Development of the antrum- steroid growth factors and electrolytes 100-200 times higher here thaan other parts of the body. Liquor folliculi-
38
What are Granulosa Cells
derived from epithelial tissue, proliferate as oocyte enlarges directly surround oocyte (species specific), produce aromatase to to convert testosterone to estrogen.
38
what does gnrh do
GnRH stands for Gonadotropin-Releasing Hormone. It is a key hormone in the regulation of the reproductive system, and it's secreted by the hypothalamus.
low frequency pulses
release lh and fsh
-high frequency pulses
very little fluctuation in men
significant fluctuations in women
38
What does the Liquor Folliculi do
Provides nutrients to the oocyte.
Supports oocyte maturation during the follicular phase.
39
what happens during day 1-5 of the ovarian cycle
Develop primary follicles
40
What happens during day 6-10 of menstruation
: Primary follicle (initially 25)àAtresia (deteriorate): Function is to produce significant amount of estrogen à The follicle that develops the fastest begins secreting estrogen at a rapid rate and cause a negative feedback to the hypothalamus causing FSH production to decrease making other folliclesàsecondary follicle – estrogen in high levels. Follicles with fewer FSH receptors will not be able to develop further, thus undergoing atresia.
41
what are the Characteristics of secondary Graafian follicle
cteristics of secondary Graafian follicle:
§ Increase LH receptors on thecal cells-bind LH for increased Plasminogen Activator and icreased production of androstenedione as a testosterone precursor
§ increase vascularity in thecal cells
§ increase inhibin to decrease FSH production
42
what happens on day 13 of the mentrual cycle
Graafian follicle – spike in LH – follicle ruptures, thecal cells stay behind, granulosa cells continue with egg, leaving the ovary
43
What is Mittlesmerz
Mittelschmerz is the pain or discomfort experienced during ovulation.
43
What happens during Day 14 of the menstrual cycle
Ovulation
Both FSH and LH are needed for ovulation to occur
o LH peak is noted prior to ovulation due to a gradual increase in estrogen
o Plasminogen Activator- a protease which thins the follicular wall strip for ovulation. Initially, it was thought that FSH was the stimulus for plasminogen activator, but now it is known that LH is equally potent to stimulate plasminogen activator.
o Day 12-13- Both FSH and LH are needed for ovulation to occur, FSH= a rise in estrogen which = a rise in LH receptor expression on the mature follicle making it sensitive to increased LH during this time.
43
What hormone is higher during Follicular Phase (First Half
FSH
44
What are the functions of FSH in the menstrual cycle
causes an increase in LH receptors on granulosa cells
causes follicular growth
increases the activity of
45
Describe the Follicular Phase (Second Half
Now a decrease in FSH is noted, while an increase in estrogen from follicular production, and an increase in LH, inhibin, and E2 are noted. Estradiol and inhibin produced by the dominant follicle cause a decrease in FSH this increases the testosterone/estradiol ratio in the non-dominant follicle. More testosterone= atresia (death of that follicle)
46
What spikes during ovulation
Spike in LH
47
an increase in E2 causes...
an increase in number of GnRH receptors on the hypothalamus
48
What is the second half of the mentrual cycle called
luteal phase
49
What happens during day 15-17
corpus hemorrhagicum – outer thecal cells with blood center
49
What happens to a pregnant woman during day 18-28
If fertilization of egg occurs, the zygote releases a hormone hcG that maintains the corpus luteum which in turn will release progesterone to maintains the endometrium for implantation and vascularity of the endometrium.
50
What happens during day 18-28 in the menstrual cycle
corpus luteum
o Corpus luteum lifecycle varies, depending on whether a female is pregnant or not.
51
What happens to a non pregnant woman during 18-28
A decrease in progesterone levels out about 14 days post ovulation, begin the process of luteolysis. The breakdown of the corpus luteum into the corpus albicans, then the process starts over
52
What happens during day 29-31
corpus albicans –
Luteal Phase - Second half of the entire cycle - During this phase of the cycle an increase in progesterone, and estradiol are noted.
A decrease in LH and FSH are seen during this time.
53
Thecal cells are...
analogous
54
Explain Granulosa Cells
early in cycle (analogous to )have only FSH receptors – LH receptors develop later from increased estrogen levels so they can bind to LH for the second ½ of the cycle. FSH induces granulosa cells to express LH receptors, when circulating LH binds to the receptors proliferation of granulosa cells stops.
55
further explain estrogen
Estrogen levels decrease after menopause and there are E2 receptors on osteoblasts.
56
What are the three types of estrogen
1. Estrone (E1)
Produced by: Primarily by the ovaries and adipose tissue (fat cells), especially after menopause.
2. Estradiol (E2)
Produced by: Ovaries, particularly by the granulosa cells of developing follicles.(active)
3. Estriol (E3)
Produced by: Primarily by the placenta during pregnancy, as well as by the liver in smaller amounts.
Function: The dominant estrogen during pregnancy
57
What are the two phases of Cycles of the Endometrial Lining
1. Proliferative phase- due to production of estradiol from the developing follicles the endometrium gradually thickens.
2. Secretory Phase- during the second half of the cycle the endometrium maintains thickness and begins to increase vascularity for implantation of the zygote and also increases glandular secretions. A decrease in hormonal levels (progesterone and estradiol) causes atrophy of the new vascularity which allows for sloughing of the endometrial lining.
58
A continual and gradual increase in progesterone=
woman has entered luteal phase or is pregnant
59
What happens to a womans temperature after ovulation
Basil body temperature 0.5-1.6 degree increase due to progesterone
60
What does the vaginal fluids look like during and not during ovulation
Fertile mucus: During the fertile window, mucus becomes clear, slippery, and stretchy (similar to raw egg whites). This type of mucus helps sperm swim and survive, making it the most fertile phase.
Non-fertile mucus: After ovulation, cervical mucus tends to become thicker, sticky, and cloudy (or dry). This type of mucus is not as conducive to sperm survival and travel.
61
explain the appearance of the cervix during ovulation and not during
Fertile Cervix:
Position: During the fertile window, the cervix becomes higher and softer.
Texture: The cervix feels soft and open, similar to the feel of the tip of your nose.
Openness: The cervix opens slightly to allow sperm to enter the uterus more easily.
Non-Fertile Cervix:
Position: After ovulation, the cervix moves lower in the vaginal canal.
Texture: It feels firm and closed, similar to the feel of your chin.
Closed: The cervix is more closed off, making it harder for sperm to pass through.
62
what are the three types of birth control
1.combined pill (estrogen and progesteroen)
2.Progesterone-Only Contraceptives (Progestin-Only)
3.iii. Contraceptive Patches, NuvaRing (Vaginal Rings)
62
what does birth control do
prevents ovulation by suppressing the release of gonadotropins.
a. Progesterone has a negative feedback on the release of GNRH. Progesterone tells the hypothalamus to stop producing GNRH. Decrease estrogen production because no follicles are being produced – less able to support egg plantation. Progesterone inhibits sperm penetration through the cervix.
63
Describe the RU486 – morning after pill
(Mifepristone) – abortifacient
95% effective in first 50 days of pregnancy
Note-progesterone inhibits uterine contractions and a decrease in progesterone increases uterine contractions.
64
what is the first phase of pregnancy?
The zygote enters the uterus
64
what is the second phase of pregnancy?
Implantation-
a. At this time the "blastula" has two separate cell layers.
65
what happens with pregnancy and the corpus luteum during fertilization
Fertilization typically occurs in the fallopian tube when a sperm cell meets and fuses with an egg (oocyte).
The fertilized egg becomes a zygote and begins its journey toward the uterus for implantation.
66
Describe the Cytotrophoblast
the inner cell mass that makes up the components of the embryo.
67
Describe the Syncytial Trophoblast
The outer layer of the trophoblast that actively invades the uterine wall, rupturing maternal capillaries and thus establishing the interface between maternal blood and embryonic extracellular fluid.
68
When is HCG produced
When the egg implants
69
When fertilization occurs, what hormone is released?
Human Chorionic Gonadotropin
Pregnancy tests detects HCG in the urine or blood
Ovulation tests detect LH
70
What produces HCG
The placenta
71
When is hcg produced
6-7 days after fertilization but may not be detectable until 8-9 after fertilization
72
How long do HCG levels rise
Until 9 weeks and then start dropping off
73
What is the function of HCG
maintains the luteal phase to increase and maintain progesterone by the corpus luteum and the production of relaxin, used by fertility specialists in lieu of LH to trigger ovulation-
74
What should happen by week 10
The corpus luteum stops producing progestrone and estrogen and the placenta slows down production of HCG. This is to allow the babies hormones to dominate and the placenta to produce enough progesterone and estrogen for the baby.
75
What are the two functions of relaxin
1. Relaxes the uterus
Keeps the myometrium (uterine muscle) calm to support implantation
2.Relaxes the pelvin ligaments
76
Where is relaxin produced?
Its produced by the corpus luteum and is stimulated by HCG. Later in pregnancy, its produced by the placenta
77
Explain progestrone
Produced by the corpus luteum up to six weeks post conception and then by the placenta from 6 weeks until the end of the pregnancy.
78
What is the function of progesterone
a. Maintains the endometrial lining (decidua)
Keeps the uterine lining thick, vascular, and nutrient-rich to support the implanted embryo.
Prevents menstruation by inhibiting endometrial shedding.
b. Inhibits uterine contractions
Relaxes the myometrium (smooth muscle of the uterus), preventing early labor or miscarriage.
Helps maintain a quiescent (inactive) uterus throughout most of pregnancy.
C.Maintain uterine vascularity and thickness, maintains uterine relaxation prior to delivery. Inhibits FSH and LH production during pregnancy. Initiates the development and growth of breast tissue.
79
What is Braxton-Hicks/preterm labor
1.Irregular, mild contractions of the uterus that can occur throughout pregnancy, especially in the second and third trimesters.
Also called "practice contractions".
Characteristics:
Do not lead to cervical dilation.
Irregular in timing and intensity.
Often go away with rest, hydration, or a change in position.
2.preterm labor can result in preterm birth
80
What is Placenta Previa/abruptia
1.A condition where the placenta partially or completely covers the cervix (the opening to the uterus).
2.A condition where the placenta detaches prematurely from the uterine wall before delivery.
81
estriol (estradiol, E2) is...
is the major estrogen produced during pregnancy in the corpus luteum.
Maintains endometrial thickness, upregulates oxytocin receptors in endometrium
82
What does LH during pregnancy do
increased levels of progesterone causes decreased levels of LH secretion
b. increased levels of estrogen causes a decrease in LH synthesis
82
What is Human placental lactogen (chorionic somatomammotropin) produced by
The syncytiotrophoblast of the placenta
83
What does Human placental lactogen (chorionic somatomammotropin) do
Decreases maternal insulin sensitivity, increasing maternal blood glucose (so more glucose is available to the fetus)
Increases lipolysis (fat breakdown) in the mother so she uses fat for energy, saving glucose for the fetus
84
What is α-feto proteins and what do they do
a glycoprotein produced mainly by the fetal liver, yolk sac, and (in smaller amounts) the gastrointestinal tract during development.
It is the fetal equivalent of albumin (the major plasma protein in adults).
Helps maintain osmotic pressure in the fetal circulation.
May bind and transport various substances (e.g., fatty acids, bilirubin).
May have immunosuppressive roles to protect the fetus from maternal immune response.
85
Increased levels of α-feto can lead to...
decreased indicates...
1. Twins or triplets, fetal death, tube or abdominal defects
2.chromosome abnormalities (down syndrome), maternal conditions like diabetes
86
explain breast feeding
This mechanism suppresses release of GnRH
2. This mechanism stimulates the release of endorphins, which suppress the release of GnRHà decrease chance of pregnancy when breast feeding
87
what is D.O.C. – deoxycorticosterone
Deoxycorticosterone (DOC) is a steroid hormone that belongs to the group of mineralocorticoids, which are involved in regulating electrolyte balance, specifically sodium and potassium.
mineral corticoid causes salt and water retention (20 times increase)
88
what are Tubuloalveolar cells
specialized epithelial cells that line structures in glandular tissues, particularly in exocrine glands.
Secretion: Tubuloalveolar cells are involved in the secretion of substances like milk (in mammary glands) and prostatic fluid (in the prostate).
These cells have both ductal and secretory functions, meaning they can modify and transport secretions as they pass through the tubules or sacs.
89
What are Ductal Cells
epithelial cells that form the ducts through which secretions pass from the glandular tissue to the external environment or to internal cavities. They are typically involved in the transportation of glandular secretions.
In mammary glands, ductal cells line the lactiferous ducts that transport milk to the nipple.
90
What is Prolactin (secretory cells
Prolactin is a hormone produced by the anterior pituitary gland. It plays a crucial role in lactation (milk production) and has other important roles in reproductive health, metabolism, and immune regulation.
Decrease in progesterone as well after placenta leaves mother-increase in milk formation.
91
An increase in suckling causes...
an increase in PRL. PRL levels are high at parturition but drop off significantly about three days after birth.
92
what is Oxytocin: Milk letdown- Myoepithelial cells
muscle cells that serve to contract to squeeze milk into the ductules
93
What is a neural relfex and why is milk letting one?
Stimulation of the nipple or a stimulatory thought process (hearing a baby crying) initiates release of oxytocin from the posterior pituitary gland to cause contraction of the Myoepithelial cells and smooth muscle cells of the ampulla. These contractions cause milk: to be released from the breast.
94
what is Parturition
baby birth
95
effects of Fetal ACTH
Increases cortisol synthesis
b. Causes shift from progesterone production to more estrogen production
c. Ratio change increases uterine contracting through increase in prostaglandin production
