L18: Female Reproduction, Gametes Flashcards
1
Q
What two important reproductive functions occur in the ovaries?
A
1) Oogenesis (maturation of female gametes)
2) Hormone production
2
Q
Oogenesis and hormone production are cyclical processes controlled by which two hormones?
A
LH and FSH
3
Q
___ are the sites where fertilization and the first cell divisions of the fertilized egg occurr
A
Fallopian tubes (oviducts)
4
Q
If fallopian tubes are injured, one runs the risk of developing what type of pregnancy?
A
Ectopic
5
Q
What cells line the oviducts?
A
Peg cells
- they are secretory
6
Q
What does the mucus secreted by the peg cells contain?
A
Nutrients for survival of egg and sperm
7
Q
True or False: in the fallopian tubes, sperm can survive for several days and become capacitated (acquire ability to penetrate egg)
A
True
8
Q
How does the fertilized egg get to the uterus?
A
Mucosa contains ciliated cells, allows for transport
9
Q
The function of the fallopian tubes is controlled by what two hormones?
A
1) Estrogen
2) Progesterone
10
Q
What lines the uterus?
A
Endometrium (epithelium containing mucous/uterine glands)
11
Q
True or False: 2/3 of the myometrium are lost with menstruation
A
False - 2/3 of the endometrium are lost with menstruation
12
Q
True or False: Endometrium and myometrium are sensitive to estrogen and progesterone + their functions are synchronized with the ovaries
A
True
13
Q
___: the smooth muscle cells that make up the walls of the uterus
A
Myometrium
14
Q
___: the cells of the male and female reproductive system that combine to make new life (the zygote)
A
Gametes
15
Q
_____ is the process that matures viable gametes
A
Gametogenesis/oogenesis
16
Q
What is the end product of the mitotic step of oogenesis?
A
Primary oocytes
17
Q
True or False: In meiosis, oogonia (germ cells) divide several times, producing daughter cells that are DIPLOID and IDENTICAL to the mother cell (same # of chromosomes)
A
False - this occurs during mitosis
18
Q
____ consists of two subsequent divisions that ultimately produce haploid daughter cells
A
Meiosis
19
Q
_____: an oocyte that has completed the first meiotic division
A
Secondary oocyte
20
Q
____: an oocyte that has completed the second meiotic division
A
Mature ovum
21
Q
True or False: Any mistakes made during meiosis will translate to genetic defects to zygote
A
True
22
Q
How many chromatids do the haploid daughter cells of meiosis have after second meiotic division?
How many chromatids do the cells of meiosis have AFTER the first meiotic division?
A
1 chromatid, 23 chromosomes
2 chromatids, 23 chromosomes
23
Q
In females, what is the end product of meiosis?
A
One haploid daughter cell
24
Q
True or False: In females, only two oocytes are ovulated and after fertilization only three zygotes are formed
A
False - in females only ONE oocyte is ovulated and, after fertilization, only ONE zygote is formed
25
Why is ONE oocyte ovulated in females and, after fertilization, only ONE zygote formed?
Asymmetric cytokinesis
26
____: Uneven distribution of cytosol between the daughter cells
Asymmetric cytokinesis
27
True or False: At the end of each of the two meiotic divisions, one cell "steals" all of the cytoplasm of its sister cell
True
28
What are the cells that are deprived of cytoplasm known as?
Polar bodies
29
Which polar body has 23 chromosomes/cell and 2 chromatids/cell?
Which polar body has 23 chromosomes/cell and 1 chromatid/cell?
First polar body = 23 chromosomes /
2 chromatids
Second polar body = 23 chromosomes / 1 chromatid
30
Where does oogenesis take place?
Ovaries
31
At the primary oocyte stage, the developing gametes become surrounded by cell systems known as ____
follicles
32
Why are follicles essential to oocyte survival?
Follicles provide oocytes with nutrients and protection
33
True or False: Oogenesis and follicular development proceed in parallel
True
34
True or False: In females, meiosis is initiated and completes within first 4 to 5 months of fetal life
False - in female, MITOSIS is initiated and completed within first 4 to 5 months of fetal life
35
Once the series of mitotic divisions has completed, can the number of primary oocytes be increased further?
No - once series of mitotic divisions are done, you CANNOT increase the # of primary oocytes further
36
True or False: The max number of gametes a women will ever have is achieved AFTER birth
False - max number of gametes that a women will eve have is achieved BEFORE birth
37
When does the first meiotic division begin?
Right after 1 oocyte stage has been reached (4-5 months of gestation)
38
The first meiosis division is interrupted and can resume only after puberty, more precisely, right before ____, when the correct concentration of ___ becomes available
ovulation; LH
39
True or False: After the 1st meiotic division has been completed, the 2nd meiotic division starts but is again interrupted
True
40
Under what conditions will the second meiotic division be completed?
If fertilization (fusion with sperm) occurs
41
Meiosis starts once the cell is a ____
A. Primary oocyte
B. Secondary oocyte
C. Tertiary oocyte
A. Primary oocyte
42
When is the first meiotic division completed?
Ovulation
43
When is the second meiotic division completed?
After fertilization
44
At what period of time do the 1 oocytes become surrounded by the primordial follicles?
4th-5th month of gestation
45
True or False: 1 oocytes that do not acquire follicles will die
True
46
True or False: Most of the follicles in the ovaries, at any point during a women's life, are primordial follicles
True
47
Beginning in childhood, groups of primordial follicles (cohorts) periodically initiate a phase of development under the effect of ____
local GF
48
*When the primordial follicles surrounding each oocyte begin to proliferate and differentiate, what cell types do they become?
Granulosa cells
49
What are the follicles called when cells surrounding each oocyte begin proliferating and differentiating into granulosa cells?
Primary follicles
50
As the number of granulosa cells grow, they arrange themselves into concentric layers. Following this, an additional layer of cells known as ____ is acquired from differentiation of stromal cell (of ovary).
At this point, what are follicles called?
theca cells
Follicles are either secondary/pre-antral follicles
51
Pre-antral follicles can only develop further AFTER puberty. Why is this?
Only after puberty are the proper concentrations of FSH, LH, and estrogen available
52
Prior to puberty, what is the max stage of development follicles can reach?
Pre-antral stage (secondary)
53
After puberty, under the stimulus of FSH, LH, and estrogen, pre-antral follicles grow further and their granulosa and thetca cells proliferate.
Granulosa cells make abundant fluid rich in nutrients and GF's. Once fluid accumulates, it generates a ___
Therefore, you have ___ follicles
antrum
antral follicles
54
Once antrum is generated, antral follicles can complete their maturation and become ___ follicles
Graafian follicles
55
During ovulation, which follicles rupture and release the secondary oocyte?
Graafian follicles
56
True or False: For each cohort of recruited cells, only one will reach this fully mature stage
True
57
After ovulation, the ___ oocytes, surrounded by a few layers of granulosa cells, is released, moves away from ovary and is captured by fimbriae of the fallopian tubes.
secondary oocyte
58
The ruptured ___ follicle keeps the position it previously occupied on the ovaries and its cell re-arrange to form _____
Graafian follicle; corpus luteum
59
The conversion of pre-antral follicles into __ follicles, and then the maturation of ___ follicle, ovulation, and activation of corpus luteum takes place during _____
antral folicles; Graafian follicles; menstrual cycle
60
From the 4th to 5th month of gestation, oocytes and their surrounding follicles undergo a process of apoptosis known as ___
atresia
61
Each women stats her life with a certain ___, or a finite number of oocytes/follicles (about 5 to 6 million)
ovarian reserve
62
True or False: The number of oocytes and associated follicles determines number of oocytes and follicles recruited in a cohort
True
63
In younger women, will the cohorts that enter the menstrual cycle have less or more follicles compared to older woman?
In younger women, the cohorts that enter the menstrual cycle will have MORE follicles
64
Where does the synthesis of ovarian hormones occur?
In cells of developing follicles of recruit cohorts
65
As a women approaches age 50, what two things decline?
1) Less follicles in each cohort
2) Less hormonal output by the ovaries
- this decline causes menopause
66
True or False: In general, younger oocytes are healthier and more likely to be successfully fertilized than "older" oocytes
True
67
The menstrual cycle leads to what two events?
1) Maturation of the Graafian follicle and ovulation
2) Alterations of female reproductive system that favors fertilization and then implantation of conceptus
68
Average days that menstrual cycle lasts?
28 days
69
What are the three phases of the menstrual cycle?
1) Follicular: 13-14 days
2) Ovulatory: 1 day
3) Luteal: 13-14 days
70
What hormone dominates the follicular phase? What hormone dominates the luteal phase?
Follicular phase = estrogen
Luteal phase = progesterone
71
From Day 1-7 of the follicular phase, what occurs?
Pre-antral follicles are converted into antral follicles (via FSH and estrogen)
72
What occurs on day 7 of the follicular phase?
Selection of dominant antral follicle
73
The dominant antral follicle develops from days __ to ___, while also secreting a great deal of ____
7-14; estrogen
74
Approximately what day does the ovulatory phase occur?
Day 15
75
During what phase of the menstrual cycle does LH surge and the Graafian Follicle undergo ovulation?
Ovulatory Phase
76
After ovulation (Day 16-25) the Graafian follicle becomes a ____ and secretes what two hormones
Corpus luteum; progesterone/estrogen
77
At Day 25 of the menstrual cycle, what occurs?
Degeneration of corpus luteum
78
During the final stages of the menstrual cycle (day 25-28) what happens?
Decline in progesterone and estrogen
Sloughing
79
During the first two weeks of the menstrual cycle, a cohort of pre-antral follicles starts developing under the influence of ______
pituitary hormones (FSH, particularly)
80
Do follicles make hormones
Yes
81
Why is estrogen so important during the first half of the menstrual cycle?
Estrogen supports the development of follicles and induces changes in reproductive tract
82
Match the days of the menstrual period to the following action:
Dominant antral follicle develops further and drastically increases production of estrogen, thereby elevating estrogen levels
A. Day 1 to Day 4 or 5
B. Day 4 or 5 to Day 7
C. Day 7 to Day 14
C. Day 7 to Day 14
83
Match the days of the menstrual period to the following action:
Decline in pituitary release of FSH induces death of all EXCEPT one of the antral follicles of the cohort. The surviving follicle—the most healthy and capable of making estrogen—is the dominant antral follicle
A. Day 1 to Day 4 or 5
B. Day 4 or 5 to Day 7
C. Day 7 to Day 14
B. Day 4 or 5 to Day 7
84
Match the days of the menstrual period to the following action:
Pre-antral follicles mature into antral follicles
A. Day 1 to Day 4 or 5
B. Day 4 or 5 to Day 7
C. Day 7 to Day 14
A. Day 1 to Day 4 or 5
85
High levels of estrogen lead to release of ___ from pituitary gland
LH
86
Completion of first meiotic division and development of the Graafian Follicle are the direct consequences of which event?
LH surge
87
_____ describes the bursting of the Graffian follicle and release of the oocyte
Ovulation
88
If fertilization has not happened by day 25-28, what occurs?
Corpus luteum undergoes luteolysis (apoptosis) and hormone production stops
89
What hormone is most abundant during the luteal phase and most importatnt for implantation and maintenance of pregnancy?
Progesterone
90
When does the hormonal output of the corpus luterum peak?
Day 21 of menstrual cycle
91
What is the purpose of the corpus luterum?
Make large amounts of hormone
92
In the early part of luteal phase (day 16-25) the oocyte is release and the remaining cells of the Graafian follicle are modified into ___ and ___ cells of the corpus luteum by the elevated __
granulosa; theca cells; LH
93
What are the three stages of menstrual cycle in the endometrium?
1) Menstrual Phase - Day 1-5
2) Proliferative Phase - Day 5-15
3) Secretory Phase - Day 16-28
94
Which phase of the menstrual cycle in the endometrium does this statement correspond with?
"When hormonal support by corpus luteum is withdrawn, endometrium becomes necrotic and is expelled from uterus"
A. Menstrual Phase (Day 1-5)
B. Proliferative Phase (Day 5-15)
C. Secretory Phase (Day 16-28)
A. Menstrual Phase (Day 1-5)
95
Which phase of the menstrual cycle in the endometrium does this statement correspond with?
"Endometrium grows back in response to elevated estrogen levels."
A. Menstrual Phase (Day 1-5)
B. Proliferative Phase (Day 5-15)
C. Secretory Phase (Day 16-28)
B. Proliferative Phase (Day 5-15)
96
True or False: Estrogen favors contractility of smooth muscle cells of the uterus and fallopian tubes
True
97
Under the influence of ____, proliferation stops and glands that are embedded in the endometrium start releasing ____, ___, and ___ that favor implantation and pregnancy
(Secretory phase - day 16-28)
progesterone
GF, nutrients, cytokines
98
True or False: Progesterone favors relaxation of smooth muscle of uterus and fallopian tubes
True
99
What four hormones are released by the brain (hypothalamus/pituitary) and important for controlling the menstrual cycle?
1) Kiss-1
2) GnRH
3) FSH
4) LH
100
What three hormones are released by the cells of the follicles/corpus luteum (ovaries) and are important for controlling the menstrual cycle?
1) Estrogen
2) Progesterone
3) Inhibin
