Chapter 27 Reproduction Flashcards
What are the primary sex organs called?
gonads
What are gonads?
- Produce gametes - sperm and eggs
- Produce sex hormones
What are the male and female sex hormones?
Male - Testosterone
Female - Estrogen and Progesterone
What are the accessory reproductive organs?
Ducts
Glands
External Genitalia
Where is the penis?
Within the spongy urethra
What is the the penis made up of?
3 Cylindrical bodies of erectile tissue - corpus spongiosum and paired corpus cavernosa
What is the corpus spongiosum?
- Erectile tissue of the penis
- Surrounds the urethra
What is the corpus cavernosa?
- Erectile tissue of the penis
- Paired - lie on dorsal aspect of the penis
What is an erection?
Erectile tissue fills with blood, causing penis to enlarge and become rigid
What are the male accessory glands?
Seminal Vesicles
Prostate
Bulbourethral Glands (Cowper’s Glands)
What do the seminal vesicles produce?
Viscous, alkaline fluid (high pH)
What % of total volume of semen is produced in the seminal vesicle?
70%
The duct leaving the seminal vesicle joins which duct? To form what?
- Joins the vas deferens to form the ejaculatory duct
Which duct carries semen?
Ejaculatory duct, NOT the vas deferens
What is semen made up of?
Fluid + sperm
Where is the prostate located?
Encircles part of the urethra
Describe the fluid secreted by the prostate?
milky + acidic (low pH)
What is the job of the prostate?
Activation of sperm
Fluid enters prostatic urethra during ejaculation
Where are the bulbourethral glands located? How big are they? What is their role?
- Pea sized, below prostate
- Act to neutralize acidic urine in the urethra
- Lubricate glands penis
When is fluid released by bulbouretheral glands? Describe it
- Fluid released before ejaculation
- Thick, clear mucousy fluid
What is the volume of semen? How many are released during ejaculation?
- 2-5 mL
- 20-150 million sperm/mL
What type of cell are most body cells?
Diploid with 23 pairs of chromosomes or 46 total
What type of cells are gametes?
Haploid with no pairs and just 23 chromosomes total
What is meiosis?
- Type of cell division occurring in the gonads that produces gametes
- Introduces genetic variation
- 2 Phases; Meiosis I and Meiosis II
What does meiosis do to the chromosomes?
Halves chromosomes from 2n to n
What is the end product of meiosis II?
4 haploid daughter cells
What happens in Meiosis I?
Pairs line up and separate
What happens in meiosis II?
Chromatids separate 2 haploid daughter cells
What is spermatogenesis? Where does it occur?
sperm production
- sequence of events that produce sperm in the semiferous tubule of the testes
What are the 3 phases of spermatogenesis?
Mitosis
Meiosis
Spermiogenesis
What happens during mitosis of spermatogenesis?
Spermatogonia produce spermatogens
What happens during meiosis of spermatogenesis?
Spermatocytes form spermatids
What happens during spermiogenesis?
Spermatids become sperm
What is another name for a sertoli cell?
Nurse cell or sustantacular cell
What is the role of a sertoli cell?
Aid in development of sperm
- Provide nutrients and signals to dividing cells
- Dispose of excess cytoplasm
- Secrete testicular fluid into lumen to transport sperm
Who regulates the hormones in male reproductive function?
hypothalamus
What does the hypothalamus release?
GnRH (Gonadotroppin-releasing hormone)
What does GnRH do?
Stimulates secretion of FSH and LH from the pituitary gland
What is the role of FSH?
Forces nurse cells to release androgen-binding protein (ABP) which makes spermatogenic cells receptive to testosterone
What is the role of LH?
M- stimulates intersitial cells to release testosterone
F - ovulation
Where are follicles found?
ovaries
What are the follicle stages of development?
Primordial
Primary
Secondary
Graafian
What type of cells make up primordial follicles? What stage is the oocyte?
- Made up squamous-like follicle cells
- Oocyte is primary
What type of cells make up the primary follicle? What stage is the oocyte? What is unique about the primary follicle?
- Cuboidal and columnar
- primary oocyte
Has not finished meiosis I - still 2n cell
What type of cells make up the secondary follicle? What stage is the oocyte? What is unique?
- 2 or more layers of granulosa
- primary oocyte
- 1n, haploid cell
What is the graafian follicle? What stage is the oocyte?
- Fluid filled space between granulosa cells collapses to form central antrum
- primary oocyte
What is ovulation? What develops?
- Ejection of the 2ndary oocyte from a ripe follicle
- Develops a corpus leuteum at site of ruptured follicle after ovulation
What is the corpus leuteum filled with?
progesterone
What do oviducts have?
Ciliated fimbriae to create current to catch oocyte after ovulation
What is the ampulla?
Enlarged area near fallopian tube, site of fertilization
What are the 3 layers of the uterine wall?
Perimetrium - outter
Myometrium
Endometrium
What type of muscle is the perimetrium?
Outer serous layer
What type of muscle is the myometrium?
Smooth muscle layer
What type of muscle is the endometrium?
Inner mucosal lining plus
Inner stratum functionalis
Outer stratum basalis
What is the role of the inner stratum functionalis?
Responds to hormone cycles, shed monthly
What is the role of the Outer stratum basalis?
NOT responsive to hormone changes, NOT shed monthly, but forms the new stratum functionalis
What is oogenesis?
Production of female gametes - eggs
When are primary oocytes formed?
Diploid started in prophase I of meiosis I
When does oogenesis begin?
fetal period
What’s the first stage of oogenesis? What happens next?
Oogonia
- Then divide to product primary oocyte, which arrest development in prophase I then eggs live in primordial follicle
What happens to the eggs after puberty?
One oocyte is selected to resume meiosis to produce 2 haploid cells, called the secondary oocyte + polar body
Secondary oocyte arrests in which phase of meiosis II?
Metaphase II
What happens to the oocyte after metaphase II?
Secondary oocyte then travels down the oviduct and is potentially fertilized, completes meiosis Ii to yield ovum and second polar body
What happens if no fertilization?
Goes through atresia and dies
In the 28 day female cycle, GnRH causes what?
Release of FSH and LH from anterior pituitary
What do FSH and LH cause in the female cycle?
Trigger growth of follicles and estrogen, resulting in increased estrogen levels
What type of effect does high estrogen have?
positive feedback mid cycle
What day does the LH surge occur? What are the effects?
Day 14
1) Meiosis I Complete
2) Triggers Ovulation
3) Growth of Corpus Leutum
What type of oocyte is ovulated?
Secondary oocyte
What happens if pregnancy does not occur between day 26 and 28?
Corpus luteum degenerates and ovarian hormone levels drop off, cycle starts all over again
What is the uterine cycle? What are the phases?
Cyclic changes in endometrium in response to ovarian hormones
1) Menstrual
2) Proliferative
3) Secretive
What happens during the menstrual phase?
Day 1-5
Hormones at lowest level
Gonadotropins are starting to rise
Stratum functionalis is shed and flow occurs
What happens during the proliferative phase?
Day6-14 pre-ovulation
Estrogen promotes growth of a new functional layer, increases synthesis of progesterone receptors in endometrium
What happens during the secretory phase?
Day 15-28
Progesterone becomes dominant hormone
Further development of endometrial lining
Glyocgen secretion
Formation of cervical mucus plug
What is menopause?
Declinign estrogen levels/menses cease for entire year
Atrophy of reproductive organs and breasts
What are symptoms of menopause?
Mood changes and irrability, depression
Hot flashes
Thinning of skin
Bone loss
Increased blood levels of cholesterol and lower levels of HDL
What are mammary glands?
Modified sweat glands with lobules and alveoli that produce milk
What is breast cancer? What are the risk factors?
Arrises from epithelial cells of small ducts
1) early menstruation late menopause
2) NO pregnancies or 1st pregnancy late in life
3) Family history
What phase of the uterine cycle is the uterus developing in response to estrogen?
proliferative
What are 10% of breast cancer cases caused by?
Hereditary defects including BRCA 1 and 2
What are 70% of breast cancer cases caused by?
NO risk factors
What are the 3 bacterial STDs?
Gonorrhea
Syphillis
Chlamydia
What is gonorrhea
Infection of mucosae of the reproductive and urinary tract
Treated with antibiotics
What are the phases of Syphillis symptoms?
phase 1 - painless, lasts few weeks
phase 2 - rash, fever, join pain
phase 3/tertiary syphillis - affects CNS, blood vessels, bones and skin
Treated with Penicillin
If congenitally infected, what happens to baby?
Stillborn or dies shortly after birth
What is chlamydia?
- Most common in USA
- Urethritis, penile or vaginal discharge, can cause arthritis and sterility in women
- Treated with tetracycline
What are the 2 viral stds?
Genital warts
Genital Herpes
What are genital warts?
HPV virus
2nd most common std
increases risk of cancer
What is genital herpes?
Herpes simplex virus type 2
latent (invisible) and flare up periods
Fetal malformations
Treated with acylovir and antiviral
