Reproductive systems

Question 1

What are the major cell types of the testes?

Answer 1

• Spermatagonia (germ cells)
• Sertoli cells (nurse cells)
• Interstitial cells (cells of leydig)

Question 2

Spermatagonia

Answer 2

The germinal cells from which sperm are produced by meiosis

Question 3

Sertoli cells

Answer 3

Aid the growth and development of sperm

Question 4

Interstitial cells

Answer 4

Produce male sex hormone testosterone

Question 5

Testicular torsion

Answer 5

Twisted spermatic cord - if not surgically treated patient will lose testis.

Question 6

What is semen?

Answer 6

The fluid medium in which sperm swim

Question 7

What glands produce semen?

Answer 7

• The prostate
• Seminal vesicle
• Bulbourethral

Question 8

Describe semen composition

Answer 8

Mainly water, also contains proteins, fructose, salts and mucus.

Question 9

How many sperm are in the average ejaculation?

Answer 9

280-500 million sperm

Question 10

Prostate cancer

Answer 10

Prostate enlarges/ becomes cancerous and blocks the urethra

Question 11

Symptoms of prostate cancer

Answer 11

• Difficulty/pain when passing urine
• Frequent nocturnal urination
• Elevation of prostate specific antigen in the blood

Question 12

Erection

Answer 12

• Blood vessels of the penis dilate, spongy erectile tissue quickly fills with blood
• Erections are under the control of the parasympathetic nervous system, not under conscious control
• Most occur during sleeping hours
• Men under 40 will have 11 a day

Question 13

Describe the process of spermatogenesis

Answer 13

• Spermatocytogenesis (Mitosis): Stem cells (spermatogonia) near the tubule wall divide by mitosis to produce more spermatogonia and primary spermatocytes.
• Meiosis: Primary spermatocytes undergo Meiosis I (producing secondary spermatocytes) and Meiosis II (producing haploid spermatids), each with 23 chromosomes.
• Spermiogenesis: The round spermatids transform into streamlined spermatozoa, forming an acrosome, flagellum (tail), and condensing their nucleus, while shedding excess cytoplasm.
• Spermiation: Mature sperm are released from the Sertoli cells into the tubule lumen

Question 14

What are the physiological roles of testosterone?

Answer 14

Testosterone’s physiological roles are vast, impacting sexual development, reproduction, metabolism, and overall health in both males and females, primarily driving male physical traits (muscle mass, bone density, hair growth, deep voice), maintaining libido and sperm production, promoting red blood cell formation, regulating fat distribution, influencing mood and energy, and supporting heart and metabolic health

Question 15

How is temperature of the testes regulated?

Answer 15

• Testes are located outside of major body cavities because their optimum temperature (35 degrees) is 2 degrees lower than core body temperature.
• This is the optimum temperature for spermatogenesis
• Testes are located in the scrotum, lined by a layer of smooth muscle called the dartos. In cold conditions, dartos contracts to to “gather” the scrotum and lift the testes closer to trunk of the
  body (warming effect). In warm conditions the dartos muscle relaxes and the scrotum becomes looser allowing the testes to hang further away from the trunk (cooling effect).

Question 16

What is the role of the prostate gland?

Answer 16

Produce semen

Question 17

Describe the physiology of the ovaries

Answer 17

• Produce eggs (oogenesis)
• Secrete hormones oestrogen and progesterone

Question 18

Describe the physiology of the fallopian tubes

Answer 18

The fallopian tube’s physiology centers on capturing the egg (oocyte) from the ovary, facilitating fertilization with sperm, and transporting the resulting embryo to the uterus, achieved through coordinated muscular contractions (peristalsis) and sweeping motions of tiny hair-like cilia lining its mucous membrane, all while providing a nutrient-rich environment and immune support for gametes and early embryos.

Question 19

What keeps the vagina acidic?

Answer 19

Lactic acid produced by lactobacillus

Question 20

Cervical cancer

Answer 20

• Third most common type of cancer in women
• Development is gradual
• Most cases involve patients with HPV

Question 21

Risk factors for cervical cancer

Answer 21

• Infection from HPV
• Early first intercourse
• Multiple sexual partners
• Herpes/chlamydia
• Certain birth control pills (combined pill makes you more susceptible to HPV and chlamydia hence more susceptible to cervical cancer)
• HIV

Question 22

Ovarian cycle

Answer 22

Monthly series of events associated with the maturation of an ovum (egg)

Question 23

Menstrual cycle

Answer 23

Series of cyclic changes that the uterine endometrium goes through each month in response to the ovarian hormones in the blood. Typically every 28 days.

Question 24

Phases of the ovarian cycle

Answer 24

• Follicular phase - period of follicle growth (days 1-14)
• Ovulation (typically occurs mid cycle around day 14)
• Luteal phase (days 14-28) period of corpus luteum activity

Question 25

Follicular phase

Answer 25

- Regulated by follicle stimulating hormone (FSH) produced by anterior pituitary gland - Follicle enlarges and starts to produce oestrogen - The antrum (a fluid filled cavity) starts to form within the follicle - The follicle matures into the graafian follicle and the pressure within increases - Ovulation occurs

Question 26

Ovulation

Answer 26

- Occurs in response to a sudden rise in the levels of luteinising hormone (LH) - Ovulation occurs when the ovary wall ruptures and expels the ovum - Mittelschmerz - a twinge of pain sometimes felt at ovulation

Question 27

Luteal phase

Answer 27

- After ovulation, ruptured follicle collapses to form the corpus luteum (yellow body) - Corpus luteum secretes progesterone and small amounts of oestrogen - Progesterone acts to maintain the endometrial lining for implantation and throughout the pregnancy should implantation be successful. - If pregnancy does not occur: corpus luteum degenerates in 10 days leaving a scar corpus albicans. - If pregnancy does occur: corpus luteum produces progesterone until the placenta takes over that role (at about 3 months)

Question 28

Uterine/menstrual cycle

Answer 28

- Puberty: begins with menarche or first episode of menstrual bleeding - Menopause: cessation of menstrual cycles - Amenorrhea: absence of menstrual cycle

Question 29

Menstrual phase

Answer 29

- Days 1-5: uterus sheds all but deepest part of endometrium

Question 30

Proliferative phase

Answer 30

- Days 6-14: Endometrium rebuilds itself under the influence of oestrogen

Question 31

Secretory phase

Answer 31

Days 15-28: Endometrium prepares for implantation of the embryo, the hormone progesterone stimulates the release of "uterine milk" from the endometrium.

Question 31

Menses (periods)

Answer 31

- If fertiliztion does not occur, progesterone levels fall, depriving the endometrium of hormonal support - Cells in the endometrium begin to die - Blood vessels in the endometrium dilate allowing blood to glow freely - The rush of blood and fragments of endometrial wall then pass out of the body during menses

Question 32

How can changes to oestrogen levels at the time of the menopause affect bone health?

Answer 32

- Rapid Loss: With less oestrogen, osteoclast activity increases, and bone is lost faster than it's made. - Weakening Bones: This imbalance leads to thinner, less dense bones, a condition known as osteoporosis. - Increased Fracture Risk: Fragile bones are more prone to fractures from low-impact falls, often becoming the first sign of osteoporosis. - Vulnerable Areas: The spine, hips, and wrists are common fracture sites.

Question 33

FSH

Answer 33

Follicle stimulating hormone - Promotes the maturation of ovarian follicles

Question 34

Oestrogen

Answer 34

- Released from developing follicles and promotes thickening and ripening of the endometrium

Question 35

LH

Answer 35

Luteinising hormone - Reaches a peak around day 14 of the cycle and promotes ovulation

Question 36

Progesterone

Answer 36

Initiates secretory phase of uterine cycle, preparing uterus for implantation. Helps to maintain the integrity of endometrium through pregnancy.