Jan 29 - The Reproductive System Flashcards

1
Q

What is reproduction dependant on?

A

It depends on the union of male and female gametes to form a new individual. The male and female reproductive systems are designed to enable the union of genetic material

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the primary reproductive organs?

A

The gonads. In males, they consist of a pair of testes. In females, they consist of a pair of ovaries. In a developing fetus, these are bi-potential gonads (they could go either way; testes or ovaries)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the functions of mature gonads?

A
Producing gametes (gametogenesis)
-Spermatozoa (sperm) in males
-Ova (eggs) in females
Secreting sex hormones
-Testosterone in males
-Estrogen and progesterone in females
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the reproductive tract?

A

A system of specialized ducts that transport or house gametes after they are produced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are accessory sex gland?

A

They empty supportive secretions into reproductive tract (the female breasts are considered accessory sex organs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is external genitalia?

A

Externally visible portions of the reproductive system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are secondary sexual characteristics?

A

External characteristics that are not directly involved in reproduction that distinguishes males and females (body configuration, hair distribution)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the male reproductive functions?

A

Production of sperm (spermatogenesis)

Delivery of sperm to female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the organs of the male reproductive system?

A

Testes
Accessory sex glands
Penis
Male reproductive tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the testes

A

They are the sperm-producing organs. They are suspended outside the abdominal tract in a skin-covered sac (scrotum)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the male accessory sex gland? What is their function?

A

They include the seminal vesicles, the prostate gland and the bulbourethral glands. Their secretions provide the bulk of semen (liquid substance that is conductive to sperm viability)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the function of the penis with regards to reproduction?

A

It is the organ used to deposit semen in the female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What makes up the male reproductive tract?

A

The epididymis, the ductus (vas) deferens, the ejaculatory duct, which empties into the urethra (the canal running the length of the penis that empties into the exterior

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the functions of the female reproductive system?

A

Cyclical production of the ova (oogenesis)
Reception of sperm
Transport of sperm and ovum to common site for union (fertilization or conception)
Maintenance of the developing fetus until it can survive in the outside world (gestation or pregnancy)
Giving birth to the baby (parturition)
Nourishing the infant after birth by milk production (lactation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the product of fertilization?

A

The embryo. After the first two months of intrauterine development, the embryo is known as a fetus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the female reproductive organs?

A

Oviducts
Uterus
Vagina
Vulva

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe the oviducts

A

They are inclose association with the ovaries
They pick up ova on ovulation
They serve as the site for fertilization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the functions of the uterus?

A

It is responsible for maintenance of the fetus during development
It is responsible for expelling at the end of pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe the vagina

A

Muscular, expandable tube that connects the uterus to the external environment
The lower portion is called the cervix
The vaginal opening is located in the perineal region between the urethral opening and the anal opening
Partially covered by thin mucous membrane, hymen (typically disrupted by first sexual intercourse)
Labia minora and labia majora are the skin folds that surround the vaginal and urethral openings
The clitoris is a small erotic structure located at the anterior end of folds of labia minora

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe the cervix

A

It is a single, small opening that serves as a pathway for sperm. It also serves as a passageway for the delivery of the baby from the uterus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the vulva?

A

A collective term for the female external genitalia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How are body cells (somatic cells) different than gametes cells?

A

They contain 46 chromosomes (diploid number) that can be sorted into 23 homologous pairs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe gametes

A

They have 23 chromosomes (haploid number)

They contain only one member of each homologous pair of chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How is gametogenesis accomplished?

A

By meiosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are autosomes?

A

22 pairs of chromosomes which code for general human characteristics and specific traits such as eye colour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are sex chromosomes?

A

The remaining pair chromosomes. There are two genetically different types; the larger X chromosome and the smaller Y chromsome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Describe gametogenesis

A

Nuclear division in the specialized case of gametes is accomplished by meiosis. Only a half of the genetic information is distributed to each of the four new daughter cells. More than 8 million (223) different mixtures of the 23 paternal and maternal chromosomes are possible. This genetic mixing provides novel combinations of chromosomes. Crossing-over contributes even further to genetic diveristy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How is sex determined?

A

It depends on the combination of sex chromosomes. Genetic females have two X chromosomes. Genetic males have an X and a Y chromosome. Genetic sex is determined at the time of conception and it depends on the type of sex chromosome is contained within the fertilizing sperm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the function of the Y chromosome?

A

Responsible for all the anatomic and functional distinctions between males and females

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the three levels of differences between males and females?

A

Genetic (depends on a combination of sex chromosomes at the time of conception)
Gonadal (depends on the development of testes or ovaries, which depends on the presence or absence of the Y chromosome)
Phenotypic (the apparent anatomic sex of the individual, which is determined by gonadal sex)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

When does gonadal specificity begin to appear?

A

It appears during the seventh week of intrauterine life when the indifferent gonadal tissue of a genetic male begins to differentiate into testes under the influence of sex-determining region of the Y chromosome (SRY)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is phenotypic sex?

A

The apparent anatomic sex of an individual, which depends on the genetically determined gonadal sex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is sexual differentiation?

A

The term sexual differentiation refers to the embryonic development of the external genitalia and reproductive tract along either male or female lines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

How does the male-type reproductive system develop?

A

Differentiation into a male-type reproductive system is induced by androgens, which are masculinizing hormones secreted by the developing testes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What does undifferentiated external gentials consist of?

A

Gential tubercle, paired urethral folds surrounding the urethral groove and more laterally, gential (labioscrotal) swellings

36
Q

How is development of the reproductive tract along the male or female line determined?

A

It is determined by the presence or abscence of two hormones secreted by the fetal testes - testosterone and Mullerian-inhibiting factor

37
Q

What does the abscence of testosterone and Mullerian-inhibiting result in?

A

The development into the female reproductive tract (oviducts, uterus and superior portion of the vagina) and the external genitalia to differentiate into the clitoris and labia

38
Q

What does the undifferentiated reproductive system consist of?

A

Undifferentiated gonads at the ends of Wolffian ducts, and Mullerian ducts

39
Q

How does happens to the undifferentiated reproductive system?

A

In the presence of testosterone and Mullerian-inhibiting factor, the Mullerian ducts degenerate and the gonads and Wolffian ducts develop into testes, the epididymis, the ductus deferens and seminal vesicles. In the abscence of these hormones, the Mullein ducts develop into the female reproductive tract (oviducts, uterus and the superior portion of the vagina) and the external genitalia differentiate into the clitoris and the labia

40
Q

Where do the testes descend to? When? Why?

A

The testes descend into the scrotum. The descent is usually complete by the seventh month of gestation. The location provides a cooler environment essential for spermatogenesis

41
Q

What are the functions of the testes?

A

They produce sperm, which occurs within the seminiferous tubules.
They secrete testosterone, which is produced by Leydig (interstitial) cells that lie in the connective tissue between seminiferous tubules

42
Q

What is testosterone?

A

A steroid hormone derived from cholesterol precursor molecule

43
Q

What are the 5 categories of testosterone effects?

A
Reproductive system before birth
Sex-specific tissues after birth
Other reproductive-related effects
Secondary sexual characteristics
Non-reproductive actions
44
Q

What is the result of spermatogenesis?

A

It results in many highly specialized, mobile sperm

45
Q

What is spermatogenesis?

A

A complex process by which undifferentiated diploid primordial germ cells (spermatogonia) are converted into haploid spermatozoa (sperm)

46
Q

What are the three major stages of spermatogenesis?

A

Mitotic proliferation
Meiosis
Packaging (spermiogenesis)

47
Q

Describe the mitotic proliferation stage of spermatogenesis?

A

Sperm-forming daughter cell divides mitotically twice more to form four identical primary spermatocytes

48
Q

Describe the meiosis stage of spermatogenesis?

A

Each primary spermatocyte forms two secondary spermatocytes yielding four spermatids after the second meiotic division. Theoretically, sixteen spermatozoa result from each spermatogonium that goes through this process

49
Q

What are the effects of testosterone before birth?

A

It masculinizes the reproductive tract and external genitalia.
It promotes the descent of the testes into the scrotum

50
Q

What are the effects of testosterone on sex-specific tissues after birth?

A

It promotes growth and maturation of the reproductive system at puberty.
It is essential for spermatogenesis
It maintains the reproductive tract throughout adulthood

51
Q

What are the effects of testosterone on other reproduction-related effects?

A

It develops the sex-drive at puberty

It controls gonadotropin hormone secretion

52
Q

What are the effects of testosterone on secondary sexual characteristics?

A

It induces the male pattern of hair growth (e.g., beard)
It causes the voice to deepen because of the thickening of the vocal folds.
It promotes muscle growth responsible for male body configuration

53
Q

What are the effects of testosterone on nonreproductive actions?

A

Is exerts a protein anabolic effect
It promotes bone growth at puberty
It closes the epiphyseal plates after being converted to estrogen by aromatase
It may induce aggressive behaviour

54
Q

What do spermatozoa associate with throughout development?

A

Spermatozoa remain closely associated with Sertoli cells throughout development

55
Q

What does a spermatozoan consist of?

A

Head
Acrosome
Midpiece
Tail

56
Q

Describe a spermatozoan head

A

Consists primarily of the nucleus (contains DNA)

57
Q

Describe the acrosome

A

Enzyme filled vesicle that caps the tip of the head
It is used to penetrate the ovum
It is formed by the endoplasmic reticulum and Golgi complex before these organelles are discarded

58
Q

Describe the midpiece of spermatozoa

A

It is the area where mitochondria are concentrated

59
Q

Describe the spermatozoan tail

A

It provides motility for the spermatozoan

60
Q

Where are Sertoli cells located?

A

In the seminiferous tubules

61
Q

What are the functions of the Sertoli cells located in the seminiferous tubules?

A

Form blood-testes barrier
Provides nourishment
Phagocytic function
Secretion of seminiferous tubule fluid which flushes released sperm from the tubule into the epididymis for storage and additional processing
Secretion of androgen-binding protein
Site of action to control spermatogenesis (release of inhibin; acts in a negative-feedback fashion to regulate FSH secretion)

62
Q

What is the function of the epididymis and ductus deferens?

A

Storage and concentration of sperm
Increase of sperm motility and fertility prior to ejaculation
During ejaculation, sperm are mixed with secretions released by accessory glands (seminal vesicles, prostate, gland and bulbourethral glands)

63
Q

What do the seminal vesicles provide in terms of seminal secretions?

A

They supply fructose for energy
They supply prostaglandins, which promotes smooth muscle motility in both male and female reproductive tracts (enhances sperm transport)
Provides more than half the semen
Secretes fibrinogen

64
Q

What does the prostate gland provide in terms of seminal secretions?

A

It contributes alkaline fluid that neutralizes acidic vaginal secretions
Provides clotting enzymes and fibrinolysin

65
Q

What do the bulbourethral glands provide in terms of seminal secretions?

A

They release lubricating mucus

66
Q

Name the two gonadotropic hormones that control the testes

A

The testes are controlled by the two gonadotropic hormones secreted by the anterior pituitary, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which are named for their functions in females

67
Q

How does LH affect the male reproductive system?

A

Testosterone is essential to maintaining spermatogenesis in the adult male, and it is under direct control of LH

68
Q

What stimulates the secretion of LH and FSH?

A

Secretion of both LH and FSH from the anterior pituitary is stimulated in turn by a single hypothalamic hormone, gonadotropin-releasing hormone (GnRH)

69
Q

How does the negative-feedback control of testosterone function?

A

The predominant negative-feedback effect of testosterone is to decrease GnRH release by acting on the hypothalamus, thus directly decreasing both LH and FSH release by the anterior pituitary

70
Q

What are the actions of prostaglandins on the reproductive system?

A

It promotes sperm transport by action on smooth muscle in the male and female reproductive tracts
It plays a role in ovulation
It play an important role in menstruation
It contributes to preparation of the maternal portion of the placenta
It contributes to parturition

71
Q

What are the two components of the male sex act?

A

Erection

Ejaculation

72
Q

What is the definition of erection?

A

Hardening of the normally flaccid penis to permit its entry into the vagina

73
Q

How is erection accomplished?

A

Engorgement of the penis erectile tissue with blood as a result of marked parasympathetically induced vasodilation of the penile arterioles and mechanical compression of the veins

74
Q

What are the two phases of ejaculation?

A

Emission phase

Expulsion phase

75
Q

What is the definition of emission phase?

A

Emptying of sperm and accessory sex gland secretion (semen) into the urethra

76
Q

How is the emission phase accomplished?

A

Sympathetically induced contraction of smooth muscle in the walls of the ducts and accessory sex glands

77
Q

What is the definition of expulsion phase?

A

Forceful expulsion of semen from the penis

78
Q

How is the expulsion phase accomplished?

A

Motor-neuron-induced contraction of the skeletal muscles at the base of the penis

79
Q

What are the different phases of the sexual response cycle?

A

Excitement phase
Plateau phase
Orgasmic phase
Resolution phase

80
Q

Describe the excitement phase of the male sexual response cycle

A

It includes erection and heightened sexual awareness

81
Q

Describe the plateau phase of the male sexual response cycle

A

Characterized by steadily increasing heart rate, blood pressure, respiratory rate and muscle tension

82
Q

Describe the orgasmic phase of the male sexual response cycle

A

It includes ejaculation and other responses that are collectively experienced as intense physical pleasure

83
Q

Describe the resolution phase of the male sexual response cycle

A

Return of genitalia and body systems to prearousal state

84
Q

Describe the excitement phase of the female sexual response cycle

A

Initiated by either physical or psychological stimuli

85
Q

Describe the plateau phase of the female sexual response cycle

A

Changes initiated during the excitement phase intensify

Systemic responses similar to those in male occur

86
Q

Describe the orgasmic phase of the female sexual response cycle

A

The experience in females is similar to that in males except:

  • no female counterpart to ejaculation
  • do not become refractory following orgasm
87
Q

Describe the resolution phase of the female sexual response cycle

A

Pelvic vasocongestion and systemic manifestations gradually subside
Time of great physical relaxation