male reproductive

Question 1

what are the primary sex organs called?

Answer 1

gonads

Question 2

what are the primary sex organs for males?

Answer 2

testes

Question 3

what are the 2 major function of the reproductive system?

Answer 3

• produce sex cells (gametes)
  
  • sperm - male
  • oocytes - females
• secrete steroid (sex hormones)
  
  • testosterone
  • estrogen and progesterone

Question 4

how many autosomes are in our DNA?

Answer 4

22 pairs

Question 4

what are the 2 sexes?

Answer 4

male and female gametes combine their genes to form a zygote

Question 5

what is the difference between diploid and haploid?

Answer 5

diploid: most body cells (2n)
- contain 2 sets of chromosomes
haploid: gametes
- thinks half (23 chromosomes)

Question 6

what type of division do gametes participate in?

Answer 6

meiosis - number of chromosomes cut in half
- 2 rounds
produce 4 haploid daughter cells

Question 7

where do the human testes reside?

Answer 7

in the scrotum because its cooler
- 35 C

Question 7

what is the spermatic cord?

Answer 7

bundle of fibrous connective tissue containing the ductus deferens, blood and lymphatic vessels, and testicular nerve

Question 8

What are the three mechanisms to regulate temperature of testes?

Answer 8

1. cremaster: strips of the internal abdominal oblique muscle (cold temps, contracts up; warm temps, relaxes far)
2. Dartos fascia: subcutaneous layer of smooth muscle (cold temps, contracts, reduces surface area)
3. pampiniform plexus: an extensive network of veins from the testes that surrounds the testicular artery and spermatic cord (countercurrent heat exchanger)

Question 9

what are the testes?

Answer 9

combines endocrine and exocrine glands that produce sex hormones and sperm

Question 10

what is the tunica albuginea?

Answer 10

white fibrous capsule on testes

Question 10

what are seminiferous tubules?

Answer 10

ducts where sperm are produced

Question 11

what are nurse cells?

Answer 11

thick germinal epithelium
- lay in between germ cells
- protect the germ cells and help them grow

Question 12

what produces testosterone?

Answer 12

interstitial endocrine cells between tubules

Question 13

what is the blood-testis barrier?

Answer 13

formed by tight junctions between nurse cells
- separates sperm from immune system
- prevents antibodies and other large molecules in the blood from getting to germ cells

Question 14

What are the three spermatic ducts?

Answer 14

Duct of the epidermis:
- site of sperm maturation and storage
Ductus (vas) deferens:
- thick wall of smooth muscle well innervated by sympathetic nerve fibers
Ejaculatory duct:
- passes through prostate to empty into urethra

Question 15

what are the male accessory glands?

Answer 15

seminal vesicles:
- pair of glands posterior to bladder
- empties into ejaculatory duct
- 60% of semen
prostate:
- surrounds urethra and ejaculatory duct just inferior to the bladder
- 30% of semen
bulbourethral glands:
- near bulb of penis
- pre-ejaculatory secretion
- neutralize the acidity of residual urine in the urethra

Question 16

what is Benign prostatic hyperplasia?

Answer 16

• noncancerous enlargement of the prostate
• compresses urethra and obstructs flow of urine
• promotes bladder and kidney infections

Question 17

what is prostate cancer?

Answer 17

• tumors tend to be near the periphery of the gland where they do not obstruct urine flow
• Digital rectal exam
• diagnosed from elevated levels of serine protease and acid phosphatase in blood

Question 18

what is the penis?

Answer 18

it is a three cylindrical bodies of erectile tissue fill with blood during sexual arousal and account for erection
- single corpus spongiosum along ventral side of penis
- two corpora cavernosa

Question 19

sympathetic vs parasympathetic?

Answer 19

symp: ejaculation
para: erection

Question 20

adolescence?

Answer 20

period from onset of gonadotropin secretion and reproductive development to when a person attains full adult height
- testosterone sustains the male reproductive tract, sperm production, and libido

Question 21

puberty?

Answer 21

first few years of adolescence until the first ejaculation of viable sperm in boys
- growth of sex hormones
- DHT
- stimulates sperm production and libido

Question 22

what does the hypothalamus produce?

Answer 22

GnRH: stimulates anterior pituitary cells to secrete:
- Follicle-stimulating hormone: stimulates nurse cells to secrete androgen-binding protein that bind testosterone, keeping it in seminiferous tubule lumen to stimulate spermatogenesis
- luteinizing hormone: stimulates interstitial endocrine cells to produce testosterone

Question 23

things that change when men age?

Answer 23

• testosterone secretion declines with age (peak at 7mg/day at age 20; declines to 1/5 by age 80)
• Andropause (male climacteric): declining reproductive function, age related drop in testosterone and triggers rise in FSH & LH
• erectile dysfunction: the ability to produce or maintain an erection sufficient for intercourse

Question 24

treatments for erectile dysfunction?

Answer 24

• Viagra, Levitra, and Cialis
  
  • phosphodiesterase inhibitors
• Sexual stimulation triggers nitric oxide secretion, which activates cGMP, which then
  increases blood flow into erectile tissue

Question 25

what is spermatogenesis?

Answer 25

process of sperm production in seminiferous tubules

Question 26

what are the three principal events of spermatogenesis?

Answer 26

1. division and remodeling of large germ cells into small, mobile sperm cells with flagella
2. reduction of chromosome number of one-half
3. shuffling of genes so each chromosome contains new gene combinations that did not exist in parent
   
   • ensures genetic variation in the offspring

Question 27

what is a spermatozoon?

Answer 27

head:
- nucleus contains haploid set of chromosomes
- acrosome - enzymes cap over the apical half of the nucleus that contains enzymes that penetrate the egg
Tall in 3 regions:
- midpiece contains mitochondria around axoneme of the flagella, produces ATP for flagella movt

Question 28

what is semen?

Answer 28

a mixture of seminal fluid and sperm - fluid expelled during orgasm
- func: provide a nutrient pH protected, enzyme containing, fluid medium for the sperm to travel in
Prostate: thin milky white fluid
- calcium, citrate and phosphate ions
- clotting enzyme
seminal vesicle: contribute viscous yellowish fluid
- causes retentions of sperm in vagina