Reproductive System Flashcards
1
Q
Germ Cells
A
Known as gametes
Sperm and secondary oocyte
2
Q
Fertilization
A
Produces one cell with one set of chromosomes from each parent
3
Q
Gonads
A
Produce gametes and secrete sex hormones
4
Q
Reproductive Systems
A
Gonads, ducts, glands, and supporting structures
5
Q
Sexual Reproduction
A
Each offspring has 2 parents and receives genetic material from both
Provides genetic diversity and is considered the foundation for the survival and evolution of a species
6
Q
Asexual Reproduction
A
Identical copy
7
Q
Sperm
A
Gamete that has motility
Has the Y chromosome
8
Q
Egg/Ovum
A
Contains most of the nutrients for the developing zygote
9
Q
Primary Sex Organs
A
Organs that produce the gametes
Testes or ovaries
10
Q
Secondary Sex Organs
A
Essential for reproduction
Male: ducts, glands, and the penis that deliver sperm cells
Female: uterine tubes, uterus, and vagina that receive the sperm and nourish the developing fetus
11
Q
Secondary Sex Characteristics
A
Features that develop at puberty to attract a mate
Pubic, axillary, and facial hair; scent glands; body morphology; low-pitched voice (males)
12
Q
Sex Chromosomes
A
Our cells contain 23 pairs of chromosomes (22 pairs of autosomes and 1 pair of sex chromosomes)
Males have 4 haploid cells
13
Q
Development of Gonads
A
Begins at 6 weeks as the gonadal ridges
Located near the primitive kidneys (mesonephrons)
14
Q
Mesonephric Ducts
A
Develop into the male reproductive system (paramesonephric ducts degenerate)
15
Q
Paramesonephric Ducts
A
Mullerian Ducts
Develop into female reproductive tract (mesonephric ducts degenerate)
16
Q
SRY Gene
A
Sex-Determining Region of the Y Gene
Codes for protein that causes the development of testes
Secrete testosterone and secrete Mullerian-inhibiting factor to degenerate the paramesonephric ducts
17
Q
5-6 Weeks
A
Development of gonads
Wolffian duct
Mullerian duct
SRY gene secretes TDF (teste determining factor)
18
Q
8-9 Weeks
A
Testes secrete Mullerian-inhibiting factor
19
Q
9-12 Weeks
A
Development of external genitalia Genital tubercle (M: penis, F: clitoris) Urogenital folds (M: urethra, F: labia minora) Labioscrotal folds (M: scrotum, F: labia majora)
20
Q
Androgen-Insensitivity Syndrome
A
Genetically male, but have all female features
Testosterone is secreted, but target cells lack the receptors for the hormone
21
Q
Somatic Cells
A
Diploid cells
23 pairs of chromosomes for a total of 46 (each pair is homologous and in the same order)
22 autosomes and 1 pair of sex chromosomes
22
Q
Gametes
A
Haploid cells
Single set of chromosomes for a total of 23
Produced by meiosis
23
Q
Prophase I
A
Chromosomes become visible, mitotic spindle appears, nuclear membrane and nucleoli disappear
Synapsis, crossing-over, and genetic recombination
24
Q
Synapsis
A
All copies of homologous chromosomes pair off forming a tetrad
25
Crossing-Over
Portions of chromatids are exchanged between any members of the tetrad
Parts of maternal chromosomes may be exchanged with paternal ones
26
Metaphase I
Homologous pairs of chromosomes line up along metaphase plate in the middle with attached microtubules
27
Anaphase I
Each set of homologous chromatids held together by a centromere are pulled to opposite ends of the dividing cell
Centromere doesn't split
28
Telophase I and Cytokinesis
Similar to mitotic division
| Result is 2 cells with haploid number of chromosomes
29
Meiosis II
Similar to meiosis I, but the centromeres split and the sister chromatids separate and move toward opposite poles of the cell
Net result is 4 genetically unique haploid cells/gametes
30
Mitosis
Split apart sister chromatids
| 2 diploid cells
31
Puberty
Period from onset of gonadotropin secretion until first menstrual period or first ejaculation of viable sperm
Reproductive system remains dormant until this time
10-12 in most boys, 8-10 in most girls
32
Adolescence
Ends when a person attains full adult height
33
Female Reproductive System
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Ovaries produce ova and hormones
Uterine tubes transport fertilized ova
Uterus is where fetal development occurs
Vagina and external genitalia constitute the vulva
Mammary glands produce milk
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34
Ovary
Pair of organs, size of unshelled almonds, found in the upper pelvic region
35
Regional Histology of the Ovary
Tunica albuginea
Cortex
Medulla
Germinal epithelium
36
Tunica Albuginea
Capsule of dense connective tissue
37
Cortex
Region deep to the tunica, contains follicles
38
Medulla
Composed of connective tissue, blood vessels, and lymphatics
39
Germinal Epithelium
Simple epithelial covering over the ovary
40
Follicular Stages
1. Primordial
2. Primary
3. Secondary
4. Graafian
5. Ovulation
Takes 290 days for all stages to happen
41
Corpus Luteum
Ovulation wound; follicle after egg is ovulated
| Fills in with hormone secreting cells (progesterone) to sustain uterine lining
42
Corpus Albicans
White scar left after follicular stages
43
Oogonia
Germ cells from yolk sac migrate to ovary and become oogonia
Oogonia divide to produce millions by mitosis as a fetus, but most degenerate (atresia)
Hormones cause meiosis I to resume in several follicles so meiosis II is reached by ovulation
Penetration by the sperm causes final stages of meiosis
44
How many oogonia present at birth?
200,000 to 2 million
45
How many oogonia remain at puberty?
40,000 but only 400 mature during a woman's life
46
Uterine Tube
Narrow, 4 inch tube extends from ovary to uterus
| Infundibulum, ampulla, isthmus
47
Infundibulum
Open, funnel-shaped portion near the ovary
| Fimbriae are moving, finger-like processes
48
Ampulla
Central region of the tube
49
Isthmus
Narrowest portion that joins the uterus
50
Histology of the Uterine Tube
Mucosa (ciliated columnar epithelium with secretory cells to provide nutrients and cilia to move the ovum)
Muscularis (circular and longitudinal smooth muscle to move ovum via peristalsis)
Serosa (outer serous membrane)
51
Function of the Uterine Tube
1. Fimbriae sweep oocyte into the tube
2. Cilia and peristalsis move it along
3. Sperm reaches oocyte in ampulla, fertilization occurs within 24 hours
4. Zygote reaches uterus about 7 days after ovulation
52
Anatomy of the Uterus
Site of menstruation and development of fetus
3 inches long by 2 inches wide and 1 inch thick
Subdivided into fundus, body, isthmus, and cervix
Contains uterine cavity accessed by cervical canal (internal and external os)
53
Position of the Uterus
Anteflexion: normally projects anteriorly and superiorly over the urinary bladder
Retroflexion: posterior tilting of the uterus
54
Histology of the Uterus
Endometrium
Myometrium
Perimetrium
55
Endometrium
Simple columnar epithelium
Stroma of connective tissue and endometrial glands
Stratum functionalis: shed during menstruation
Stratum basalis: replaces functionalis each month
56
Myometrium
3 layers of smooth muscle
57
Perimetrium
Visceral peritoneum
58
Blood Supply to the Uterus
Uterine arteries branch off iliac arteries as arcuate arteries and radial arteries that supply the myometrium
Straight and spiral branches
Spiral arteries supply the stratum functionalis; constriction via hormonal changes starts menstrual cycle
59
Hysterectomy
Surgical removal of uterus caused by endometriosis, ovarian cysts, excessive bleeding, cancer
60
Complete Hysterectomy
Removes the cervix
61
Radical Hysterectomy
Removes uterus, tubes, ovaries, part of vagina, pelvic lymph nodes, and supporting ligaments
62
Vagina
Passageway for birth and menstrual flow
4 inch long fibromuscular organ ending at the cervix
Orifice partially closed with hymen
63
Histology of the Vagina
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Mucosal layer (stratified squamous epithelium and areolar connective tissue; large stores of glycogen breakdown to produce acidity)
Muscularis layer (smooth muscle that allows considerable stretch)
Adventitia (loose connective tissue that binds it to other organs)
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64
Vulva (Pudendum)
Mons pubis
Labia majora and minora
Clitoris
Bulb of vestibule
65
Mons Pubis
Fatty pad over the pubic symphysis
66
Labia Majora and Minora
Folds of skin encircling vestibule where you find the urethral and vaginal openings
67
Clitoris
Small mass of erectile tissue
68
Bulb of Vestibule
Masses of erectile tissue just deep to the labia on either side of the vaginal orifice
69
Breasts
Mounds of tissue overlying the pectoralis major
Nipple surrounded by the areola
Suspensory ligaments attach it to skin and muscle
If nonlactating, contains a little glandular tissue
70
Mammary Glands
Modified sweat glands that produce milk
Milk-secreting glands open by lactiferous ducts at the nipple
Amount of adipose tissue determines the size of the breasts
71
Female Reproductive Cycle
Controlled by monthly hormones FSH, LH, and GnRH
72
Ovarian Cycle
Changes in the ovary and after maturation of the oocyte
73
Uterine Cycle
Preparation of the uterus to receive a fertilized ovum
| If implantation does not occur, the stratum functionalis is shed during menstruation
74
Puberty
Triggered by rising levels of GnRH which stimulate anterior pituitary to produce FSH and LH
75
FSH stimulates...
Follicles to secrete estrogen and progesterone
2nd sex organs maturation, increase in height and width of pelvis
Prepares uterus for pregnancy
76
Thelarche
Development of breasts
77
Pubarche
Growth of pubic and axillary hair, apocrine and sebaceous glands
78
Menarche
First menstrual period
| Requires at least 17% body fat in teenager, 22% in adult
79
Climacteric
Midlife change in hormone secretion accompanied by menopause
| Caused by a decrease in follicles (about 100 remaining)
80
Effects of Climacteric
Less secretion of estrogen and progesterone
Atrophy of uterus, vagina, and breasts
Skin thins out, bone mass declines, risks of CVD increase
Hot flashes
81
Hormone Replacement Therapy
Low dose of estrogen and progesterone
82
Hormonal Regulation of Reproductive Cycle
1. GnRH secreted by hypothalamus
2. Stimulates anterior pituitary to secrete FHS and LH
3. FSH initiates growth of follicles that secrete estrogen; estrogen maintains reproductive organs
4. LH stimulates ovulation and promotes formation of corpus luteum (secretes estrogens, progesterone, relaxin, and inhibin)
83
Progesterone
Prepares uterus for implantation and mammary glands for milk secretion
Lowers blood cholesterol
Inhibits release of GnRH, FSH, and LH
84
Relaxin
Facilitates implantation in the relaxed uterus
85
Inhibin
Inhibits secretion of FSH
86
Sexual Cycle
Averages 28 days but ranges from 20 to 45
Hypothalamus to pituitary to ovaries to uterus
Follicular phase and postovulatory phase
87
Follicular Phase
2 weeks
Menstruation occurs during first 3-5 days of cycle
Uterus replaces lost endometrium and follicles grow
88
Postovulatory Phase
2 weeks
Corpus luteum
Endometrium lost again if pregnancy does not occur
Progesterone peaks
89
Menstrual Phase
FSH, LH, and estrogens rise
Menstruation lasts for 5 days (first day is beginning of cycle)
In ovary: FSH stimulates granulosa cells to secrete estradiol to inhibit GnRH
In uterus: declining levels of progesterone cause spiral arteries to constrict; stratum functionalis is slaughed off
90
Preovulatory Phase
Lasts from day 6 to 13
Follicular phase in the ovary: estrogen and inhibin slow secretion of FSH; dominant follicles survive to day 6; graafian follicle enlarges through days 1-14; estrogen triggers LH
Poliferative phase of uterus: estrogen levels repair and thicken the stratum functionalis
91
Ovulation
Rupture of follicle and release of second oocyte on day 14
Increasing levels of estrogen stimulate release of GnRH, which stimulates anterior pituitary to release more LH
Corpus hemorrhagicum results
92
Signs of Ovulation
Increase in basal body temperature
Changes in cervical mucus
Cervix softens
Mittelschmerz pain (14-40 years of age)
93
Postovulatory Phase
Lasts 14 days
Luteal phase in the ovary: corpus albicans forms and progesterone drops while GnRH, FSH, and LH rise (if no fertilization); developing embryo secretes hCG which maintains corpus luteum (if fertilization occurs)
Secretory phase of the uterus: hormones promote thickening of endometrium, menstrual phase begins
94
Premenstrual Syndrome
Physical and emotional distress during the postovulatory (luteal) phase
Disappears at onset of menstruation
Oral contraceptives are an effective treatment along with careful diet and exercise
95
Amenorrhea
Absence of menstruation
Hormone imbalance, extreme weight loss/low body fat
Common with athletes
96
Dysmenorrhea
Pain associated with menstruation
Severe enough to prevent normal functioning
Uterine tumors, ovarian cysts, endometriosis, or intrauterine device
97
Abnormal Uterine Bleedine
Excessive amount or duration or intermenstrual
| Fibroid tumors or hormonal imbalance
