The Reproductive System Flashcards
What are the functions of the reproductive system?
-Produce
-Nourish and transport the chromosome carrying cells
-Facilitate fertilization
-Sustain the growth of an embryo and fetus
What is the common goal of both the male and female reproductive systems?
Passing on genetic information and the continuation and procreation of the species
What are gonads?
Testes (male) and ovaries (female)
-Produce gametes and secrete sex hormones
What is a gamete?
male or female reproductive cells
What do ducts do?
store and transport the gametes
What do accessory sex glands do?
produce substances to protect the gametes and facilitate their movement
What do supporting structures do?
assist in gamete delivery and growth of embryo
What are the organs of the male reproductive system?
-Testes
-System of ducts (epididymis, ductus deferens, ejaculatory ducts and urethra)
-Accessory sex glands (seminal vesicles, prostate, bulbourethral)
-Supporting structures (scrotum, penis)
What is the scrotum?
-supporting structure for the testes that consists of loose skin and an underlying subcutaneous that hangs from the root of the penis
-divided by a septum that allows each testicle its own compartment
-skeletal muscle fibers exist within the scrotum and the scrotal septum that allow for the extension and retraction of the scrotal sac
-this allows for thermoregulation using body heat, in order to keep the testes 2-3C cooler than internal body temperature, required for adequate sperm production
What are testes (testicles)?
-A pair of oval shaped glands housed in the scrotum
-Internally, each testicle is divided into several lobules containing the seminiferous tubules, tightly coiled tubes where sperm is formed
-After the sperm is formed, it travels through a series of ducts that empty into a single ductus epididymis
What is spermatogenesis?
The process of sperm formation
What is mitosis?
nuclear cell division producing two identical cells
What is meiosis?
reproductive cell division that occurs in the gonads
What occurs in meiosis I?
a single diploid cell produces 2 haploid cells
What occurs in meiosis II?
the two haploid cells from meiosis I divide producing 4 haploid gametes that are genetically different from the original diploid cell
What is a diploid?
a cell having 2 sets of chromosomes (XX and XY)
What is a haploid?
a cell containing half the number of chromosomes
What is sperm (aka spermatozoa)?
the male gamete (reproductive sex cell) responsible to fertilization of a female ovum
What is sperm composed of?
Composed of a head (contains chromosomes, nucleus and other enzymes) and a tail (flagella - motility of the cell)
True or False:
Sperm can survive up to 24 hours in the female reproductive tract
False
Sperm can survive up to 48 hours in the female reproductive tract
What are the steps of spermatogenesis?
- Sperm cells start as spermatogonia (sperm stem cell) and undergoes mitosis within the seminiferous tubules to become primary spermatocytes
- The primary spermatocytes then undergo meiosis I, producing secondary spermatocytes
- The secondary spermatocytes undergo meiosis II producing spermatids
- The final stage of meiosis converts the spermatids into mature sperm cells
-One spermatogonia cell produces 4 spermatozoa (sperm cells)
What is the epididymis?
an organ that curves along the superior and posterior border of each testicle
What is the function of the epididymis?
The functional site for sperm maturation and storage, and it helps propel sperm into the vas deferens during sexual arousal
What is the ductus (vas) deferens?
the continuation of the epididymis and a passageway to transport sperm from the testes to the urethra during sexual arousal (achieved by peristaltic contractions)
What are spermatic cords?
a supporting structure that ascends out of the scrotum and contains:
-vas deferens
-arteries
-veins
-lymph vessels
-autonomic nerves
-the cremaster muscle (extension and retraction)
What are ejaculatory ducts?
-formed by the union of the seminal vesicle and the terminal end of the ductus deferens
-terminate in the prostatic urethra where they eject semen into urethral canal for ejaculation
What is the urethra (male reproductive)?
-shared terminal duct of the reproductive and urinary systems for males
-common passageway for urine and semen
What is the function of the accessory sex glands?
Responsible for producing and secreting the remaining substances that produce semen
What are the male accessory sex glands?
-seminal vesicles
-bulbourethral glands
-the prostate
What are the seminal Vesicles (aka seminal glands)?
-a pair glands that lye posterior to the base of the urinary bladder and secrete about 60% of the fluid in semen
-composed of fructose, prostaglandins and clotting proteins
-the alkaline fluid helps neutralize the acidic environment of the urethra and vaginal canal that would otherwise kill
What are the bulbourethral Glands (aka Cowper’s glands)?
-small, paired glands located inferior to the prostate
-during sexual arousal they secrete an alkaline mucous fluid to neutralize and lubricate the urethra and tip of the penis
What is the prostate?
-a singular gland located inferior to the urinary bladder and surrounds part of the urethra (prostatic urethra)
-secretes a milk and slightly acidic fluid that contributes to sperm motility and viability
What is semen?
-A mixture of sperm and seminal fluid with a slightly alkaline pH
-Provides sperm with a transport medium, nutrients and protection to promote fertilization with an ovum (egg)
-Typically contains approximately 50-150 million sperm cells per mL
What is the penis?
Contains the urethra and is a passageway for semen and urine
What does the structure of the penis consist of?
-Body: contains tissues that keep the urethra open and smooth muscle contraction and blood vessel dilation to promote an erection
-Glans penis: the distal end of the penis. Widens and provides an external opening for the urethra
-Root: connective tissue that anchor the penis in place
What occurs in hormonal control of the male reproductive system?
-During puberty, the hypothalamus begins producing more gonadotropin releasing hormone (GnRH)
-This stimulates the anterior pituitary gland to begin producing more luteinizing hormone (LH) and follicle-stimulating hormone (FSH)
-LH stimulates cells within the seminiferous tubules to secrete testosterone
-FSH and testosterone work synergistically to stimulate spermatogenesis
What does testosterone do?
-Involved in prenatal development of the male reproductive system
-Development of male sex characteristics during puberty
-Enlargement of sex organs, muscular and skeletal growth, facial and chest hair growth, enlargement of the larynx (deepening voice), and increased sebaceous gland (oil) secretions
-Spermatogenesis and libido (sex drive)
-Stimulation of anabolism - protein synthesis
What are the organs of the female reproductive system
-Ovaries (female gonads)
-Uterine (fallopian) tubes (oviducts)
-Uterus
-Vagina
-External organs (vulva)
-Mammary glands (part of the integumentary and reproductive systems)
Where are the ovaries located?
Paired glands found lateral to the uterus and superior to the urinary bladder
What do the ovaries produce?
-Produce gametes (oocytes that mature into ova (eggs) after fertilization
-Produce hormones (progesterone and estrogens)
What is oogenesis?
the formation of gametes in the ovaries
True or False:
Spermatogenesis and oogenesis both occur through meiosis
True
Oogenesis occurs in the same fashion as spermatogenesis (meiosis) but starts before a female is even born (starts at puberty for males)
What is the process of oogenesis?
-Oogonia (diploid stem cells) undergo mitosis and produce primary oocytes
-The primary oocytes undergo meiosis I during fetal development but do not complete the phase until after puberty
-The primary oocytes are contained in ovarian follicles until maturation
-Following puberty, when the oocyte and follicle have matured and are ready for ovulation, the primary oocyte completes meiosis I - producing 2 haploid cells
-One of the 2 haploid cells is discarded, and the other becomes a secondary oocyte
-The secondary oocyte begins meiosis II but does not complete it until it is fertilized
-After completing meiosis II, there are two more haploid cells, one of them is discarded, the other is the ovum (mature egg)
What happens if the secondary oocyte is not fertilized?
If fertilization of the secondary oocyte does not occur, the cell degenerates
How many ovum are produced during oogenesis?
Unlike spermatogenesis, one primary oocyte produces a single ovum
What are the uterine (fallopian) tubes?
-Paired ducts that extend laterally from the uterus and provide a route for sperm to reach an ovum and transport secondary oocytes and fertilized ova from the ovaries to the uterus
-A ciliated epithelial layer and smooth muscle layer work together to propel a fertilized ova or secondary oocyte into the uterus
What are the functions of the uterus?
-the site of implantation of a fertilized ovum
-development of the fetus during pregnancy
-delivery of the infant (labor)
-it is also the source of menstrual flow and a pathway for sperm to reach the fallopian tubes
Where is the uterus located?
It is located between the urinary bladder and the rectum