Human Reproduction Flashcards

1
Q

What makes up the reproductive organs?

A
  • primary sex organs
  • ducts
  • accessory glands
  • external genitalia
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2
Q

What are the primary sex organs in male reproductive organs?

A
  • the testis
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3
Q

What are the ducts in male reproductive organs?

A
  • epididymis
  • sperm duct (vas deferens)
  • urethra
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4
Q

What are the accessory glands in male reproductive organs?

A
  • prostate gland
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5
Q

What is the external genitalia in male reproductive organs?

A
  • the penis
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6
Q

What does the scrotum contain?

A
  • the scrotum contains the testis
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7
Q

What are the functions of the scrotum?

A
  1. The scrotum acts as a temperature regulator
  2. The scrotum houses and protects the testis
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8
Q

At what temperature does the scrotum keep the testis?

A
  • 2 to 3 degrees Celsius lower than body temperature
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9
Q

Why is temperature regulation of the testis necessary?

A
  • the lower temperature is necessary for the formation of fertile sperm
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10
Q

What happens to the testis in cold conditions?

A
  • the testis are pulled closer to the abdomen for warmth
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11
Q

What happens to the testis in warm weather?

A
  • the testis are suspended well away from the body
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12
Q

What are the testis?

A
  • two oval structures that are suspended outside the body in the scrotum
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13
Q

Where are the testis in the embryonic stage?

A
  • the testis are in the abdominal cavity just below the kidneys
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14
Q

When do the testis descend into the scrotum?

A
  • before birth
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15
Q

What to the testis consist of?

A
  • many compartments/lobules
  • which contain highly convoluted tubules
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16
Q

What are the highly convoluted tubules contained by the lobules in the testis called?

A
  • the seminiferous tubules
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17
Q

How long are the seminiferous tubules?

A
  • they total about 250 metres in each testis
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18
Q

What lines the tubules in the lobules of the testis?

A
  • germinal epithelium
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19
Q

What lies between the tubules in the lobules of the testis?

A
  • groups of endocrine cells
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20
Q

What are the endocrine cells that lie between the tubules in the lobules of the testis called?

A
  • interstitial cells/cells of Leydig
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21
Q

What do the testis produce?

A
  1. Sperm (male gametes) by the germinal layer
  2. Testosterone (a male hormone) by the interstitial cells
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22
Q

What are the ducts included in the male reproductive organs?

A
  • epididymis
  • sperm duct (vas deferens)
  • urethra
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23
Q

What is the epididymis?

A
  • a highly convoluted tubule
  • about 5 metres long
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24
Q

How is the epididymis formed?

A
  • the seminiferous tubules join to form the epididymis
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25
Q

What are the functions of the epididymis?

A

Immature sperm enter the epididymis where they:
1. mature, to become motile and fertile
2. are stored for several months

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26
Q

What happens if sperm cells stay in the epididymis for too long?

A
  • they are broken down by the epithelial cells of the epididymis
  • re-absorbed into the body
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27
Q

What is the sperm duct (vas deferens)?

A
  • a muscular continuation of the epididymis
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28
Q

Where does the sperm duct (vas deferens) lead?

A
  • it leaves the scrotum
  • passes through the prostate gland
  • then enters the urethra
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29
Q

What is the function of the sperm duct (vas deferens)?

A
  • the sperm duct pushes mature sperm forward through ejaculation
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30
Q

What is ejaculation?

A
  • when the mature sperm are pushed forward by strong peristaltic waves
  • from the epididymis into the urethra
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31
Q

What is a peristaltic wave?

A
  • a strong contraction of smooth muscle in the walls of ducts
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32
Q

What is the urethra?

A
  • the duct at the end of the uro-genital system leading to the exterior
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33
Q

What is the function of the urethra?

A
  • forms a common duct for the transportation of semen and urine
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34
Q

What is the prostate gland?

A
  • a plum-sized gland
  • surrounds the urethra at the base of the bladder
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35
Q

What may happen to the prostate with age?

A
  • it may enlarge, exerting pressure on the urethra
  • which slows down the emptying of the bladder
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36
Q

What is the function of the prostate gland?

A
  • secretes a fluid
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37
Q

What is the function of the fluid secreted by the prostate gland?

A
  • aids the transport of the sperm
  • contains enzymes that make sperm more active
  • (this fluid makes up about 1/3 of the seminal fluid)
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38
Q

Where are the Cowper’s glands located?

A
  • at the base of the penis
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39
Q

How many Cowper’s glands does a male typically have?

A
  • 2
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40
Q

What do the Cowper’s glands produce?

A
  • an alkaline mucous-like fluid
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41
Q

When do the Cowper’s gland produce fluid?

A
  • when sexually aroused
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42
Q

What are the functions of the fluid produced by the Cowper’s glands?

A
  1. Neutralizes acidic urine that may still be present in the urethra
  2. Lubricates the urethra and external urethral opening
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43
Q

Why does the fluid produced by the Cowper’s gland need to lubricate the urethra and external urethral opening?

A
  • to protect sperm from mechanical damage during ejaculation
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44
Q

What passes down the penis?

A
  • the urethra
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45
Q

What does the penis consist of?

A
  • special spongy tissue (erectile tissue)
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46
Q

What is there running the length of the penis?

A
  • three sections of erectile tissue
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47
Q

Where are the sections of erectile tissue situated?

A
  • two sections are situated on the dorsal side
  • one section is situated on the ventral side
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48
Q

Which sections of erectile tissue are situated on the dorsal side of the penis?

A
  • the corpus cavernosa
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49
Q

Which section of erectile tissue is situated on the ventral side of the penis?

A
  • the corpus spongiosum
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50
Q

What is the primary mechanism that brings about an erection?

A
  • the dilations of dorsal and central arteries supplying blood to the penis
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51
Q

How does the dilation of the dorsal and central arteries supplying blood to the penis bring about an erection?

A
  • the dilation allows more blood to fill the three spongy erectile tissue chambers
  • causing the penis to lengthen and stiffen
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52
Q

What is unable to occur without an erection?

A
  • without an erection, sperm cannot be transferred to the female’s vagina during sexual intercourse
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53
Q

What is the function of the penis?

A
  • to deposit semen with sperm into the female’s vagina during copulation
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54
Q

What is distinctive about the human penis in terms of the erectile bone?

A
  • the human male is the only mammal that has no erectile bone in the penis
  • it relies entirely on engorgement with blood to reach its erect state
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55
Q

What is distinctive about the human penis in terms of attachment to the abdominal wall?

A
  • the human penis is not attached to the abdominal wall but hangs free
  • this is in contrast to most other mammals, where the penis is stored internally until erect
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56
Q

What is the erectile bone found in other mammals known as?

A
  • the baculum
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57
Q

What does semen consist of?

A
  • sperm from the testis
  • seminal fluid from the sperm duct and accessory glands (e.g. prostate)
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58
Q

What is the average volume of semen for an ejaculation?

A
  • 2,5 to 5ml
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59
Q

What is the average number of sperm ejaculated per ml?

A
  • 50 to 150 million per ml
  • i.e. 700 million per ejaculation
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60
Q

When is semen considered infertile?

A
  • when it has a sperm count of less than 20 million per ml
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61
Q

What is the difference between an erection and ejaculation?

A
  • an erection is the stiffening of the penis
  • ejaculation is the expulsion of semen
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62
Q

What are the female reproductive organs?

A
  • ovaries
  • accessory organs
  • external genitalia
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63
Q

What are the accessory organs in the female reproductive system?

A
  • fallopian tubes (oviduct)
  • uterus
  • vagina
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64
Q

What is the external genitalia in the female reproductive system?

A
  • the vulva
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65
Q

What are the ovaries?

A
  • 2 almond shaped organs
  • found in the pelvic cavity
  • and held in position by ligaments
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66
Q

What surrounds each ovary?

A
  • a layer of germinal epithelium
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67
Q

What are embedded in the outer layer of the ovaries?

A
  • primary follicles
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68
Q

What are primary follicles?

A
  • tiny sac-like structures
  • containing an immature egg
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69
Q

When is the total number of eggs carried by a female determined and why?

A
  • at birth
  • because females are born with all of their primary follicles
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70
Q

What does a primary follicle develop into?

A
  • a mature follicle
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71
Q

What is a mature follicle called?

A
  • a Graafian follicle
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72
Q

When does the Graafian follicle form the corpus luteum?

A
  • after ovulation (the release of an egg)
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73
Q

What are the functions of the ovaries?

A
  1. To form and release eggs
  2. To produce oestrogen and progesterone
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74
Q

How many fallopian tubes are there?

A
  • 2
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75
Q

What are the fallopian tubes?

A
  • muscular tubes lined with cilia
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76
Q

Where are the fallopian tubes situated?

A
  • they stretch from each ovary to the uterus
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77
Q

What does each fallopian tube end in?

A
  • a funnel shaped structure
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78
Q

What is the funnel shaped structure at the end of each fallopian tube called?

A
  • the infundibulum
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79
Q

What do the infundibulum have?

A
  • finger-like outgrowths
  • called fimbria
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80
Q

What are the functions of the fallopian tubes?

A
  1. Provide a pathway between uterus and ovary for eggs, sperm and the zygote
  2. Are the site of fertilisation and initial cell division of the zygote
  3. Enable the egg or developing zygote to move towards uterus (by the action of muscles and cilia)
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81
Q

What are the physical characteristics of the uterus?

A
  • hollow
  • pear-shaped
  • thick-walled
  • muscular
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82
Q

Where is the uterus situated?

A
  • between the bladder and the rectum
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83
Q

What happens to the uterus during and after pregnancy?

A
  • during pregnancy it enlarges considerably
  • soon after birth it almost returns to its original size
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84
Q

What is the lower part of the uterus called?

A
  • the cervix
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85
Q

Where does the cervix go?

A
  • it projects into the vagina
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86
Q

How large is the opening of the cervix normally?

A
  • normally only millimetres in diameter
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87
Q

Why does the cervix have an opening (aside from to birth a child)?

A
  • to allow menstrual blood to leave the body
  • and sperm to gain access
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88
Q

What keeps the uterus closed during pregnancy and why?

A
  • the sphincter muscles of the cervix
  • to prevent a miscarriage
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89
Q

What does the uterine wall consist of?

A
  • myometrium
  • endometrium
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90
Q

What is the myometrium?

A
  • a thick, involuntary muscle layer of the uterine wall
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91
Q

What is the endometrium?

A
  • a lining of the uterine wall that is richly supplied with blood vessels
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92
Q

Why do the walls of the uterus need to be thick?

A
  • so that it can stretch when a baby develops inside it
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93
Q

What happens to the endometrium at ovulation?

A
  • progesterone causes the endometrium to thicken
  • to prepare for the implantation of the blastocyst
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94
Q

What happens to the endometrium if fertilisation does not occur?

A
  • the upper layer of the endometrium becomes detached
  • and is passed out together with the unfertilised egg
  • (menstruation)
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95
Q

What are the functions of the uterus?

A
  1. The uterus is the organ in which the blastocyst implants, develops and grows
  2. The contraction of the myometrium enables the baby to be pushed out during birth
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96
Q

What does the myometrium do?

A
  • contracts to enable the baby to be pushed out during birth
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97
Q

What is the vagina/birth canal?

A
  • a muscular passage between the uterus and the outside of the body
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98
Q

What are the physical characteristics of the vagina?

A
  • it has very elastic, folded walls
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99
Q

What is the significance of the elastic, folded walls of the vagina?

A
  • this allows the vagina to stretch during intercourse and childbirth
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100
Q

What is the pH of the vagina like and why?

A
  • normally quite acidic
  • which helps keeps the vagina healthy and free from infection
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101
Q

What are the functions of the vagina?

A
  1. Is the place where sperm are deposited during sexual intercourse
  2. Forms a birth canal during birth
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102
Q

What is the vulva?

A
  • the vulva forms the external genitalia
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103
Q

What is the role of the vulva in the reproductive process?

A
  • it plays no role in the reproductive process
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104
Q

What is the clitoris?

A
  • a small mass of erectile tissue
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105
Q

Where is the clitoris found?

A
  • at the anterior end of the vulva
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106
Q

What is the clitoris the female counterpart of?

A
  • it is the female counterpart of the penis
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107
Q

What does the clitoris play a role in?

A
  • in the sexual excitement of the female
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108
Q

What is puberty?

A
  • the process of physical and physiological changes catalysed by the release of gonadotropins
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109
Q

What does puberty lead to?

A
  • the development of secondary sex characteristics
  • an immature individual (child) becoming capable of reproduction
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110
Q

What affects the age at which puberty begins?

A
  • genetic factors
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111
Q

When does puberty typically occur?

A
  • in girls: between 11 and 14
  • in boys: between 14 and 16
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112
Q

How does climate affect puberty?

A
  • puberty can start earlier in warmer climates
  • puberty can start one or two years later in colder climates
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113
Q

What is adolescence?

A
  • the period of physical, physiological and psychological change
  • that extends from the start of puberty until the age of 17 to 20 in females and 18 to 21 in males
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114
Q

How does puberty start?

A
  • the pituitary gland, under stimulation from the hypothalamus, releases gonadotropins which initiate puberty
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115
Q

What are gonadotropins?

A
  • hormones that stimulate the gonads
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116
Q

What is the gonadotropin in males?

A
  • interstitial-cell-stimulating hormone (ICSH)
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117
Q

What does interstitial-cell-stimulating hormone (ICSH) do?

A
  • stimulates the testis to secrete testosterone
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118
Q

What is the gonadotropin in females?

A
  • follicle-stimulating hormone (FSH)
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119
Q

What does follicle-stimulating hormone (FSH) do?

A
  • stimulates the ovaries to produce oestrogen
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120
Q

What does the release of testosterone and oestrogen do?

A
  • initiate changes to the gonads and to other parts of the body
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121
Q

What are the results of changes to the gonads called and why?

A
  • these result in primary sexual characteristics
  • as they influence the process of reproduction
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122
Q

What are the other physical changes aside from the changes to the gonads called and why?

A
  • secondary sexual characteristics
  • as they have nothing to do with the actual reproductive process
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123
Q

What physical changes occur in girls during puberty regarding breast tissue?

A
  • breast development occurs
  • normally the first sign of puberty
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124
Q

What physical changes occur in girls during puberty regarding hair?

A
  • growth of hair in the pubic area and armpits
  • often the second noticeable change
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125
Q

What physical changes occur in girls during puberty regarding their reproductive organs?

A
  • increase in size of uterus, ovaries and the primary follicles
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126
Q

What physical changes occur in girls during puberty regarding bone structure?

A
  • widening of pelvis (and thus the hips)
  • to provide a wider birth canal
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127
Q

What physical changes occur in girls during puberty regarding fat deposition?

A
  • deposition of fat on hips, thighs, upper arms and buttocks
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128
Q

What physical changes occur in girls during puberty regarding menstruation?

A
  • start of the 28-day menstrual cycle
  • average age of starting is between 12 and 18
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129
Q

What is the first menstrual bleeding known as?

A
  • menarche
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130
Q

What physical changes occur in girls during puberty regarding ovulation?

A
  • ovulation begins
  • (which in about 80% of girls only occurs after the first year of menstruating)
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131
Q

What physical changes occur in girls during puberty regarding physical growth?

A
  • growth spurt lasting two to three years occurs
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132
Q

What physical changes occur in girls during puberty regarding skin?

A
  • possible acne, as skin gets oilier
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133
Q

What physical changes occur in boys during puberty regarding the testis and penis?

A
  • enlargement of testis and penis
  • usually the first sign of puberty
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134
Q

When is the maximum size of the testis and penis reached?

A
  • about 6 years after the onset of puberty
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135
Q

What physical changes occur in boys during puberty regarding hair growth?

A
  • hair growth in the pubic area and armpits
  • at about 13 to 14 years
  • (facial hair only grows later)
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136
Q

What physical changes occur in boys during puberty regarding their voices?

A
  • increase in size of larynx (voice box)
  • thickening of vocal cords
  • causing the voice to deepen
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137
Q

What physical changes occur in boys during puberty regarding physical structure?

A
  • enlargement of skeletal muscles
  • broadening of shoulders
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138
Q

What physical changes occur in boys during puberty regarding sperm?

A
  • sperm production begins
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139
Q

What physical changes occur in boys during puberty regarding growth?

A
  • growth spurt of two to three years
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140
Q

What physical changes occur in boys during puberty regarding skin?

A
  • acne can occur
  • more common in boys than girls
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141
Q

What is distinctive about human males in terms of fertility?

A
  • human males are sexually fertile all the time
  • males of most mammalian species are not
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142
Q

What is distinctive about humans regarding menstruation?

A
  • menstruation is unique to humans and close primate relatives such as chimpanzees
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143
Q

How does menstruation differ in females of other placental mammal species?

A
  • they do not menstruate as they have oestrous cycles
  • in which the animal reabsorbs the endometrium if fertilisation does not occur during that cycle
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144
Q

What does ‘oestrous’ mean?

A
  • a time when females ovulate and can be impregnated
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145
Q

What is distinctive about humans in terms of mating?

A
  • mating is not confined to the period when ovulation occurs
  • this mating is designed to reinforce pair-bonding; which is especially necessary where care of the young is prolonged as in humans
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146
Q

What are nocturnal emissions and in whom do they occur?

A
  • nocturnal emissions are ‘wet dreams’
  • occur in celibate males
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147
Q

What does ‘celibate’ mean?

A
  • abstaining from sex
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148
Q

What is gametogenesis?

A
  • the formation of mature gametes by the reproductive glands (gonads)
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149
Q

What are gametes?

A
  • sperm and eggs
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150
Q

What does gametogenesis involve?

A
  • meiosis
  • a nuclear division which results in a halving of the number of chromosomes: from 46 (in body cells) to 23 (in gametes)
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151
Q

Why does meiosis occur?

A
  • to ensure that in fertilisation, the number of chromosomes returns to 46 in the zygote
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152
Q

What is a zygote?

A
  • a fertilised egg
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153
Q

What is spermatogenesis?

A
  • the sequence of events during which mature, haploid sperm are produced
  • from the germinal epithelium in the seminiferous tubules of the testis
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154
Q

What hormone is essential for the making of sperm?

A
  • testosterone
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155
Q

When does spermatogenesis occur?

A
  • it begins at puberty and continues throughout life
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156
Q

What happens to the immature sperm in spermatogenesis?

A
  • immature sperm are moved into the epididymis
  • where they mature
  • becoming motile and fertile
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157
Q

What is the summarised process of spermatogenesis?

A
  • diploid cells in the seminiferous tubules of the testis undergo meiosis
  • to form haploid sperm cells
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158
Q

What are the 4 main parts of a sperm?

A
  • head
  • neck
  • body
  • tail
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159
Q

What does the head of a sperm contain?

A
  • acrosome
  • nucleus
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160
Q

What is the purpose of the nucleus in the head of the sperm?

A
  • contains haploid set of chromosomes
  • which contains genetic material of the male
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161
Q

What is the purpose of the acrosome in the head of the sperm?

A
  • contains hydrolytic enzymes
  • to digest outer layers surrounding egg cell
  • allow sperm to penetrate
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162
Q

What is found in the body of the sperm?

A
  • mitochondria
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163
Q

What is the purpose of the mitochondria in the body of a sperm?

A
  • provides energy for movements of tail
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164
Q

What is found in the tail of a sperm?

A
  • contractile fibres
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165
Q

What is the purpose of the contractile fibres found in the tail of a sperm?

A
  • responsible for whip-like movements of tail
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166
Q

What is the typical length of a sperm?

A
  • 0,05mm
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167
Q

How long can sperm survive in the female reproductive tract once ejaculated?

A
  • about 48 hours
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168
Q

How is it possible for the sperm to survive in the female reproductive tract?

A
  • the sperm obtains nourishment from seminal fluid and female secretions
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169
Q

What is oogenesis?

A
  • the production of haploid, mature eggs
  • in the follicles of the ovaries
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170
Q

What is the difference between spermatogenesis and oogenesis in terms of the number of sperm/eggs?

A
  • in oogenesis, the number of eggs is determined before birth
  • whereas sperm are formed after puberty
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171
Q

How are oogonia produced?

A
  • by mitosis
  • and growth from the germ cells of the germinal epithelium before birth
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172
Q

What is the difference between spermatogenesis and oogenesis in terms of mature eggs and sperm?

A
  • mature sperm are formed continuously throughout life
  • mature eggs are form once puberty starts until menopause
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173
Q

What is the difference between spermatogenesis and oogenesis in terms of cycles?

A
  • oogenesis occurs in a monthly cycle
  • sperm are produced daily
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174
Q

What is ovulation?

A
  • the release of a mature egg from a Graafian follicle in the ovary
  • every 28 days
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175
Q

What is the summarised process of oogenesis?

A
  • diploid cells in the ovary undergo meiosis
  • to form a primary follicle consisting of haploid cells
  • once cell develops into an ovum contained in a Graafian follicle
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176
Q

What is the range of time of the menstrual cycle in human women?

A
  • 21 to 35 days
  • 28 days on average
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177
Q

What cycles make up the menstrual cycle?

A
  • the ovarian cycle
  • the uterine cycle
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178
Q

What are the uterine and ovarian cycles controlled by?

A
  • by the endocrine system
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179
Q

When do the uterine and ovarian cycles occur?

A
  • from puberty until menopause
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180
Q

What does the ovarian cycle consist of?

A
  • development of Graafian follicle
  • ovulation
  • formation of the corpus luteum
181
Q

What is the first part of the ovarian cycle?

A
  • the follicular phase
182
Q

What occurs during the follicular phase?

A
  1. the primary follicles mature and get ready to release an egg cell
  2. under the influence of FSH from the pituitary gland, a primary follicle develops into a fluid-filled Graafian follicle
183
Q

What happens during the process of the development of a Graafian follicle?

A
  • the primary oocyte in the follicle undergoes meiosis
  • develops into a haploid egg cell (ovum)
184
Q

What does the Graafian follicle contain?

A
  • the egg cell (ovum)
185
Q

What happens to the Graafian follicle as it matures?

A
  • it enlarges and moves to the surface of the ovary
186
Q

What is ovulation?

A
  • luteinizing hormone (LH), released from the pituitary
  • causes the Graafian follicle to rupture
  • releasing an egg cell
187
Q

When does ovulation take place?

A
  • approximately on day 14 of the cycle
188
Q

What happens after ovulation?

A
  • the remains of the Graafian follicle
  • under the influence of FSH and LH
  • changes into glandular tissue
  • called the corpus luteum (yellow body)
189
Q

What does the corpus luteum produce?

A
  • large amounts of progesterone
  • as well as oestrogen
190
Q

What happens to the corpus luteum if pregnancy does not occur?

A
  • it will begin to disintegrate and disappear 10-14 days after ovulation
191
Q

What happens to the corpus luteum if pregnancy occurs and why?

A
  • it remains
  • as it is needed to sustain a healthy pregnancy
192
Q

What makes human ovulation unique in terms of sexual activity?

A
  • human females can be sexually active at any time in their cycle, even when they are not about to ovulate
  • other mammal females are only sexually active in the oestrus phase of their cycle and are about to ovulate
193
Q

What makes human ovulation unique in terms of physical signs?

A
  • there are no obvious external signs to signal ovulation
  • it is pure chance as to whether fertilisation occurs (unlike in other animals)
194
Q

What is the uterine cycle?

A
  • a series of changes in the endometrium that is regulated by hormones
195
Q

What are the two main phases of the uterine cycle?

A
  • changes in the endometrium
  • menstruation
196
Q

What is the first step of the uterine cycle?

A
  • oestrogen is secreted from the maturing follicles
  • and starts the repair of the endometrium
197
Q

When does the repair of the endometrium occur?

A
  • days 6 to 14 of the menstrual cycle
198
Q

What happens after the repair of the endometrium?

A
  • under the influence of oestrogen and progesterone from the corpus luteum
  • the endometrium continues to thicken, becoming more glandular (secretes mucus and nutrients) and vascular (has blood vessels)
199
Q

Why does the endometrium thicken and become glandular and vascular?

A
  • to make it suitable for the implantation of a blastocyst
200
Q

What is a blastocyst?

A
  • a fertilised egg
201
Q

What happens at the beginning of menstruation?

A
  • the high levels of oestrogen and progesterone exert a negative feedback on the pituitary gland
  • inhibiting the release of the hormones FSH and LH
202
Q

What happens as a result of the inhibition of the release of FSH nd LH?

A
  • the corpus luteum degenerates and progesterone secretion is reduced and then stops
203
Q

What happens after progesterone secretion stops?

A
  • with no hormone to maintain the endometrium, the lining breaks down and is shed
204
Q

What is menstruation?

A
  • the process in which the endometrium breaks down and is shed
205
Q

What passes out through the vagina during menstruation?

A
  • the detached tissue
  • blood
206
Q

What are the two types of hormones released during the menstrual cycle?

A
  • pituitary hormones
  • ovarian hormones
207
Q

What are the pituitary hormones released during the menstrual cycle?

A
  • follicle-stimulating hormone (FSH)
  • luteinizing hormone (LH)
208
Q

What are the ovarian hormones released during the menstrual cycle?

A
  • oestrogen
  • progesterone
209
Q

What controls the secretion of pituitary and ovarian hormones during the menstrual cycle?

A
  • a simple negative feedback mechanism
210
Q

What is the signalling mechanism of the negative feedback loop?

A
  • the increased concentration of each hormone in the blood
211
Q

What happens when there is an increased level of a pituitary or ovarian hormone in the blood?

A
  • it will negatively affect or stop the release of another hormone
212
Q

What happens in step 1 of the negative feedback loop in the menstrual cycle?

A
  • under the influence of FSH a primary follicle develops into a Graafian follicle
  • and causes the ovaries to produce oestrogen
213
Q

What happens in step 2 of the negative feedback loop in the menstrual cycle?

A
  • oestrogen then stimulates the pituitary gland to produce LH
214
Q

What happens in step 3 of the negative feedback loop in the menstrual cycle?

A
  • LH causes the Graafian follicle to form the corpus luteum
  • which secretes progesterone
215
Q

What happens in step 4 of the negative feedback loop in the menstrual cycle?

A
  • the increased progesterone and oestrogen concentrations activate the negative feedback mechanism
  • which stops the pituitary glands secreting FSH and LH
216
Q

What happens in step 5 of the negative feedback loop in the menstrual cycle?

A
  • as there is no FSH a Graafian follicle will not develop
  • and no oestrogen and progesterone will be released by the ovary
217
Q

What happens in step 6 of the negative feedback loop in the menstrual cycle?

A
  • because of the low levels of oestrogen and progesterone
  • the secretion of FSH an LH is no longer suppressed
  • the whole cycle starts again
218
Q

What is menopause?

A
  • the stage at which the ovaries stop producing oestrogen and progesterone
  • and as a result, stop releasing eggs
  • and menstruation no longer occurs
219
Q

At what age do women typically reach menopause?

A
  • between the ages of 46 to 54
220
Q

What are some examples of post-menopausal conditions?

A
  • atrophy (degeneration) of the reproductive organs
  • bone mass loss
  • increasing risk of cardiac disease
221
Q

What do doctors prescribe to women going through menopause?

A
  • low-dose oestrogen-progesterone preparations
  • hormone replacement therapy (HRT)
222
Q

What is copulation?

A
  • sexual intercourse or coitus
  • the transfer of sperm into the vagina when the penis is inserted and sperm are deposited near the cervix
223
Q

When must copulation occur?

A
  • copulation must occur before fertilisation
224
Q

When is fertilisation possible?

A
  • after copulation
225
Q

What is fertilisation?

A
  • the fusion of the sperm nucleus with the egg nucleus to form a diploid cell known as a zygote
226
Q

What is gestation?

A
  • the period between conception and birth
  • during which the embryo and then the foetus develops in the uterus
227
Q

What are the steps of prenatal development?

A
  1. Early development
  2. Later development
228
Q

When is the period of early development?

A
  • 0 to end of 2 months of pregnancy
229
Q

When is the period of later development?

A
  • 3 months to birth
230
Q

What takes place during the early development stage?

A
  • fertilisation
  • blastocyst implantation and formation
  • embryo formation
231
Q

What takes place during the later development stage?

A
  • the foetal stage
232
Q

When and where does fertilisation occur?

A
  • in the outer third of the fallopian tube
  • when the nuclei of the sperm and egg fuse to form a zygote
233
Q

What happens after semen is deposited in the vagina?

A
  • sperm move through the cervix, uterus and into the fallopian tubes until they reach the egg
234
Q

What happens to the egg during fertilisation?

A
  • the egg, surrounded by follicle cells, is sucked into the fallopian tube by action of the fimbriae
235
Q

What happens during step 1 of fertilisation?

A
  1. thousands of sperm surround the egg
236
Q

What happens during step 2 of fertilisation?

A
  1. hydrolytic enzymes, released from the acrosomes, break down the follicle cells
237
Q

What happens during step 3 of fertilisation?

A
  1. only one sperm penetrates the membrane of the egg; the tail is discarded
238
Q

What happens during step 4 of fertilisation?

A
  1. the nuclei of the sperm and egg fuse, forming a diploid zygote
239
Q

What happens during step 5 of fertilisation?

A
  1. a fertilisation (egg) membrane forms immediately, which prevents other sperm from entering the egg
240
Q

What happens to the diploid zygote after fertilisation?

A
  • it divides immediately by mitosis to form two cells
241
Q

What happens after the diploid zygote divides by mitosis?

A
  • each cell divides repeatedly until a solid ball of cells is formed
242
Q

What is the solid ball formed by repeated cell division called?

A
  • the morula
243
Q

What does the morula resemble?

A
  • a mulberry
244
Q

What does the morula develop into?

A
  • it develops into a hollow, fluid-filled ball of cells
  • the blastocyst
245
Q

What is the trophoblast?

A
  • a layer formed by the outer cells forming the wall of the blastocyst
246
Q

What does ‘tropho’ mean?

A
  • it relates to feeding
247
Q

What develops from the trophoblast?

A
  • an inner cell mass develops from the trophoblast
248
Q

When does the development of the cell mass from the trophoblast take place?

A
  • as the developing embryo moves along the fallopian tube towards the uterus
249
Q

How does the embryo move along the fallopian tube towards the uterus?

A
  • it moves by combination of peristaltic waves and the rhythmic beating of the fallopian tube’s cilia
250
Q

What happens to the blastocysts a few days after it has been in the uterus?

A
  • it sinks into the thickened, highly vascular endometrium
  • this is called implantation
251
Q

When does implantation occur?

A
  • about 10 days after fertilisation
252
Q

What does the inner cell mass of the blastocyst form?

A
  • embryo
  • amnion
  • yolk sac (which forms part of umbilical cord)
253
Q

What is the amnion?

A
  • a membrane that becomes fluid-filled
254
Q

What does the trophoblast later become called?

A
  • the chorion
255
Q

What happens to the trophoblast after implantation?

A
  • develops villi
  • that grow into the endometrium to form the placenta
256
Q

What is the placenta?

A
  • a disc-shaped temporary organ
  • richly supplied with maternal and foetal blood vessels
257
Q

What does the placenta connect?

A
  • the foetus with its mother’s blood
  • at the end of the umbilical cord
258
Q

What does the placenta develop from?

A
  • the chorion and its villi (that penetrate the endometrium)
259
Q

What is the importance of the villi on the chorion that the placenta develops from?

A
  • the villi provide a large surface area of attachment of the placenta to the endometrium
260
Q

What does each placental villus contain and why?

A
  • each villus contains a capillary network
  • which provides a large surface area for exchange of substances by diffusion
261
Q

What are the placental villi surrounded by and why?

A
  • the mother’s blood
  • so that mother’s blood supply and foetal capillaries are very close to each other
262
Q

Does the foetal and mother’s blood mix? Why or why not?

A
  • no
  • because the foetal capillaries have thin walls
263
Q

How do substances move between the maternal and foetal blood?

A
  • by diffusion
264
Q

What would happen if the mother’s blood mixed with the foetal blood?

A
  • it could cause the foetal blood to clot
  • resulting in the death of the foetus
265
Q

What is the 1st function of the placenta?

A
  1. Oxygen and dissolved food substances pass from the mother to the foetal blood system for respiration and nutrition
266
Q

What are some examples of dissolved food substances that pass from the mother to the foetal blood system through the placenta?

A
  • glucose
  • amino acids
  • fatty acids
  • ions
  • vitamins
267
Q

What is the 2nd function of the placenta?

A
  1. Foetal waste products of metabolism pass into the maternal blood system for excretion
268
Q

What are some examples of foetal waste products of metabolism that pass into the maternal blood system for excretion?

A
  • urea
  • carbon dioxide
269
Q

What is the 3rd function of the placenta?

A
  1. Some maternal antibodies pass to the foetus, providing temporary passive immunity to certain diseases
270
Q

What is the result of antibodies being passed to the foetus through the placenta?

A
  • the child enjoys immunity to most infectious diseases for the first 6 months of life
271
Q

What is the 4th function of the placenta?

A
  1. The placenta acts as a barrier (micro filter)
    - preventing many pathogenic organisms and drugs from entering the foetus from the mother
272
Q

What are some examples of pathogens that can pass through the placenta to the foetus?

A
  • German measles (rubella)
  • syphilis
  • HIV
273
Q

What does the placenta do after 3 months of pregnancy? (5th placental function)

A
  1. The placenta takes over the function of secreting progesterone and oestrogen from the ovaries (corpus luteum)
274
Q

Why are progesterone and oestrogen important in pregnancy?

A
  • these hormones are essential from brining about the necessary changes in the uterus
  • and for the maintenance of pregnancy
275
Q

What does progesterone do in pregnancy?

A
  • prevents ovulation and menstruation
  • which would result in the loss of the foetus
276
Q

What does the placenta secrete late in pregnancy and why?

A
  • relaxin
  • a hormone that relaxes joints and ligaments to assist in the delivery of the baby
277
Q

What kind of harmful substances can pass though the placenta and cause significant damage to the developing embryo and foetus?

A
  • cigarette smoke (carbon monoxide and nicotine)
  • alcohol
  • illegal drugs
  • many medicines
278
Q

What is the amnion?

A
  • a membrane that surrounds the developing embryo and foetus
279
Q

What does the amnion do?

A
  • secretes a fluid called amniotic fluid that fills the amniotic cavity
280
Q

What is amniotic fluid?

A
  • fluid that surrounds the developing foetus
  • serves to provide a protective environment
281
Q

What does amniotic fluid consist of?

A
  • 99% water
  • foetal cells
  • waste products
282
Q

What do the foetal cells found in amniotic fluid contain?

A
  • foetal genetic information
283
Q

What is the 1st function of amniotic fluid?

A
  1. It supports the developing foetus, allowing it freedom to move about easily
    - and so prevents malformations due to gravity/pressure
284
Q

What is the 2nd function of amniotic fluid?

A
  1. It cushions and protects the foetus from damage by external injury or from impact from the mother
285
Q

What is the 3rd function of amniotic fluid?

A
  1. It provides a medium in which to practice breathing and swallowing movements
286
Q

What is the 4th function of amniotic fluid?

A
  1. It holds urine as it is released from the foetus
287
Q

What is the 5th function of amniotic fluid?

A
  1. It protect the foetus against changes in temperature and dehydration
288
Q

What is the umbilical cord of the foetus?

A
  • a flexible cord extending from its abdomen to the placenta
  • joins the foetus to its mother
289
Q

What does the umbilical cord contain?

A
  • 2 umbilical arteries
  • a single umbilical vein
290
Q

What is the function of the umbilical arteries?

A
  • leaves the foetus carrying waste (carbon dioxide and other excretory waste products)
  • which diffuse into the mother’s blood and are excreted
291
Q

What is the function of the umbilical vein?

A
  • enters the foetus carrying oxygenated blood and nutrients (such as glucose and amino acids) from the mother
292
Q

When is the first trimester?

A
  • the first 12 weeks of pregnancy
293
Q

What is significant about the first trimester of pregnancy?

A
  • during this time the risks of miscarriage and birth defects are highest
294
Q

What changes occur during the first trimester regarding menstruation?

A
  • the menstrual period stops
  • (a clear sign that a woman is pregnant)
295
Q

What changes occur during the first trimester regarding mood and appetite?

A
  • experiences of tiredness
  • food cravings
  • distaste for certain foods
  • mood swings
296
Q

What changes occur during the first trimester regarding sickness?

A
  • nausea or morning sickness
  • (which can occur at any time of the day and occurs in about 70% of pregnant women)
297
Q

What changes occur during the first trimester regarding a pregnant woman’s breasts?

A
  • breasts become tender and swollen
  • nipples and areolas darken
298
Q

When is the second trimester?

A
  • weeks 13 to 28 of pregnancy
299
Q

What changes occur during the second trimester regarding energy?

A
  • most women have more energy in this trimester
300
Q

What changes occur during the second trimester regarding sickness?

A
  • the symptoms of morning sickness lessen and eventually disappear
301
Q

What changes occur during the second trimester regarding the uterus?

A
  • the uterus starts expanding
  • (during pregnancy it expands up to 20 times its normal size)
  • by the end of the 2nd trimester the expanding uterus has created a visible baby bump
302
Q

What changes occur during the second trimester regarding movement of the foetus?

A
  • movement of the foetus can be felt
  • (this typically happens in the 4th month)
303
Q

What is the movement of the foetus reffered to as?

A
  • ‘quickening’
304
Q

What changes occur during the second trimester regarding the pregnant woman’s skin?

A
  • patches of darker skin can appear on the face
  • (sometimes called the ‘mask of pregnancy’)
305
Q

When is the third trimester?

A
  • weeks 29 to 40 of pregnancy
306
Q

What changes occur during the third trimester regarding weight gain?

A
  • final weight gain takes place
  • (which is the most weight gain throughout the pregnancy)
307
Q

What changes occur during the third trimester regarding movement of the foetus?

A
  • the pregnant woman feels the more frequent and stronger movements of the foetus, which can be disruptive
308
Q

What changes occur during the third trimester regarding breathing?

A
  • many women find breathing difficult
  • as the foetus presses up against the diaphragm and lungs
309
Q

What changes occur during the third trimester regarding abdominal shape?

A
  • the woman’s abdomen changes shape as it drops down quite low
  • due to the foetus turning in a downward position ready for birth
310
Q

What happens to the foetus as it turns downward to prepare for birth?

A
  • the foetal head descends into the pelvic cavity
  • (this is known as engagement of the head)
311
Q

What happens as a result of the foetal head descending into the pelvic cavity?

A
  • less pressure on the upper abdomen and breathing becomes easier
  • reduced bladder capacity which can result in weak bladder control
  • often backache
312
Q

What changes occur during the third trimester regarding the pregnant woman’s breasts?

A
  • breasts can become tender
  • may leak a water pre-milk called colostrum
313
Q

What changes occur during the third trimester regarding contractions?

A
  • muscles of the mother’s uterus start contracting
314
Q

What is it called when a pregnant woman starts experiencing contractions of her uterus in the final trimester?

A
  • these are called Braxton-Hicks contractions
315
Q

Why do Braxton-Hicks contractions occur?

A
  • as practice to help the mother’s body prepare for labour
316
Q

What is the scientific term for birth?

A
  • parturition
317
Q

What is birth?

A
  • the expulsion of the foetus, its surrounding membranes and the placenta from the uterus
318
Q

What is known about the placenta at the end of the gestation period?

A
  • the placenta is less efficient
  • for this reason alone, birth must take place
319
Q

What is distinctive about birth in humans regarding the state of the newborn?

A
  • the human baby is born at a relatively immature and helpless stage
320
Q

What would happen to the foetus if it grew any larger than normal?

A
  • it would not be able to leave the body successfully
321
Q

Why would the foetus not be able to leave the body successfully if it grew too large?

A
  • the human birth canal is narrower as a result of the process of becoming upright and bipedal
  • the human foetal brain is much larger than that in other primates and if enlarged any further would not be able to pass through the birth canal
322
Q

What is distinctive about birth in humans regarding the position in which the baby is born?

A
  • the baby is usually born headfirst
323
Q

When does the foetus move into position for birth?

A
  • 2 or 3 weeks before birth
324
Q

How must the baby lie in order for a normal birth to take place?

A
  • with its head pointing downward towards the cervix
325
Q

What happens just before the baby is born regarding hormones?

A
  • the very high levels of oestrogen in the mother’s blood cause the hypophysis to release a hormone called oxytocin
  • which promotes contraction of the uterine wall
326
Q

How many stages are there during the birth process?

A
  • 3 stages
327
Q

What are the stages of the birth process?

A
  1. Dilation of the cervix
  2. Delivery of the aby
  3. Expulsion of the placenta
328
Q

What happens during the dilation of the cervix?

A
  • the myometrium starts contracting
329
Q

What is the nature of contractions during the dilation of the cervix?

A
  • contractions are initially slow and rhythmic
  • later become intense and more frequent
330
Q

What do the uterine muscle contractions do?

A
  • force the amnion and foetus towards the cervix
  • cause the cervix of the uterus to dilate
331
Q

At what size is the cervix considered fully dilated?

A
  • about 10 centimetres
332
Q

What happens when the cervix is fully dilated?

A
  • the increased pressure causes the amnion to break and release amniotic fluid
  • which passes out through the birth canal (vagina)
333
Q

What is it commonly called when the amnion breaks and releases amniotic fluid?

A
  • ‘breaking of the waters’
334
Q

When is the baby pushed out through the vagina?

A
  • after the cervix is fully dilated
335
Q

How is the baby pushed out ?

A
  • by the very powerful contractions of both the uterine and abdominal muscles
336
Q

How is the passage of the foetus’ head through the birth canal made easier?

A
  • by the fact that the flat bones of the baby’s skull are separated by connective tissue and aren’t fused
  • allowing the head to change shape and pass though the birth canal
337
Q

When does the final stage of birth, the expulsion of the placenta, take place?

A
  • about 10 to 20 minutes after delivery
338
Q

What must first happen in order for the expulsion of the placenta to take place?

A
  • the placenta with the remaining bit of the umbilical cord comes away from the uterine wall
339
Q

How does the expulsion of the placenta take place?

A
  • uterine contractions force it out as the afterbirth
340
Q

What are mammary glands?

A
  • organs in female mammals that produce milk to feed young offspring
341
Q

Where are the mammary glands situated in humans?

A
  • in the breasts
342
Q

What are the mammary glands made up of?

A
  • milk-secreting cells
343
Q

What is lactation?

A
  • milk production
344
Q

How do milk glands and ducts come about?

A
  • during pregnancy, oestrogen and progesterone stimulate the growth and development of the milk glands and milk ducts in the breasts
345
Q

What happens after birth regarding lactation?

A
  • the hormone prolactin from the pituitary gland stimulates the mammary glands to produce milk
346
Q

What causes the release of milk from the mammary glands?

A
  • the hormone oxytocin
347
Q

Why is breast milk favoured above bottle feeding?

A
  • contains antibodies which can help a baby fight infection
  • contains all the nutrients in perfect proportions for optimal growth
  • is cheap and easy as there are no bottles to sterilise or tins to buy
348
Q

What is contraception?

A
  • the prevention of fertilisation or implantation after sexual intercourse has taken place
349
Q

What is the only method of contraception that is 100% effective?

A
  • abstinence
  • (not having sexual intercourse)
350
Q

What are the main groups that contraceptives can be divided into according to how they work?

A
  1. Prevent ovulation (egg being released)
  2. Prevent fertilisation (sperm reaching egg)
  3. Prevent embryo implantation or development
351
Q

What is the contraception method that prevents ovulation?

A
  • the pill
352
Q

What does the pill contain and what does it do?

A
  • contains oestrogen and progesterone
  • that prevent pregnancy by inhibiting ovulation and thus fertilisation
353
Q

What does the pill not protect against?

A
  • sexually transmitted infections/diseases
354
Q

What are the methods of contraception that prevent fertilisation?

A
  • sterilisation
  • condoms
  • spermicide
  • diaphragm
355
Q

What are disadvantages of sterilisation as a method of contraception?

A
  • it is usually permanent
  • individuals who use it cannot have children
356
Q

What are the advantages of sterilisation?

A
  • it does not affect the reproductive physiological processes
  • is not harmful
  • cheap
357
Q

What is male sterilisation called?

A
  • a vasectomy
358
Q

What happens in a vasectomy?

A
  • the sperm duct is cut
  • preventing the sperm from being expelled
359
Q

What happens to the sperm that are made when one has a vasectomy?

A
  • after a while they are broken down and absorbed back into the body
360
Q

How is sterilisation in females achieved?

A
  • by performing a tubal ligation
361
Q

What happens in a tubal ligation?

A
  • the fallopian tubes are tied off
  • which prevents the egg and sperm from meeting
362
Q

What is a condom?

A
  • a barrier device used during sexual intercourse to reduce the probability of pregnancy and spreading of sexually transmitted infections
363
Q

What are the physical characteristics of the male condom?

A
  • non-porous
  • very strong rubber/latex sheath
364
Q

How is the male condom used?

A
  • the condom fits over an erect penis
  • must be put on before sex begins
365
Q

How does the male condom prevent conception?

A
  • it catches the sperm and stops it from getting into the vagina
366
Q

What is an additional benefit of both male and female condoms?

A
  • they prevent viruses and bacteria from passing between sexual partners
  • therefore preventing the spread of sexually transmitted infections
367
Q

What are the physical characteristics of the female condom?

A
  • similar to a small, elongated balloon
368
Q

How does the female condom work?

A
  • it fits inside the female and lines the vagina
369
Q

What are spermicides?

A
  • chemicals that kill sperm
370
Q

What forms do spermicides come in?

A
  • creams
  • foams
  • gels
371
Q

How are spermicides used?

A
  • they are put in the vagina
  • often used with condoms as they are not very effective at preventing pregnancy on their own
372
Q

What is a diaphragm?

A
  • a barrier devise
373
Q

What are the physical characteristics of a diaphragm and how is it used?

A
  • a shallow bendable cup
  • placed over the cervix before sex and left in place for at least 6 hours after sex
374
Q

How does the diaphragm prevent pregnancy?

A
  • it prevents the sperm reaching the egg
375
Q

What are the contraceptive methods that prevent embryo implantation or development?

A
  • MAP (morning-after-pill)
  • intrauterine devices (IUDs)
  • RU 486 (mifepristone)
376
Q

What is the morning-after-pill?

A
  • a course of pills which mast be started within 72 hours of unprotected intercourse
377
Q

How does the morning-after-pill work?

A
  • it is a combination of oestrogen and progesterone which completely confuses the normal hormonal signals
  • resulting in either the prevention of fertilisation or the inability for a fertilised egg to implant
378
Q

What is an intrauterine device (IUD)?

A
  • a small object made of plastic, copper or stainless steel that is inserted into the uterus
379
Q

What does an IUD do?

A
  • prevents implantation of the blastocyst
380
Q

What is RU 486 ?

A
  • another pill that uses mifepristone
  • must be taken within the first 7 weeks of pregnancy
381
Q

How does an RU 486 pill work?

A
  • it blocks the action of progesterone so that if implantation has occurred the endometrium will disintegrate
  • resulting in a miscarriage
382
Q

What are some other contraceptive devices used?

A
  • injectables (3-month injection)
  • rhythm method
383
Q

What is the 3-month injection?

A
  • an injection that contains progesterone
  • which will prevent ovulation and increase the thickness of the cervical mucus to block the sperm from getting to the uterus
384
Q

What is the rhythm method?

A
  • a form of natural family planning wherein one avoids unprotected sex over the period of ovulation
385
Q

How are STIs/STDs transmitted?

A
  • through unprotected sex
386
Q

How can STIs affect people?

A
  • affect their general health and fertility
387
Q

How are STIs caused?

A
  • by micro-organisms such as viruses, bacteria and fungi
388
Q

In who is the incidence of STIs the highest?

A
  • people between 15-29 years old
389
Q

Why are STIs dangerous?

A
  • they weaken the body’s defences, making it much easier for HIV to enter the body
390
Q

What is the most serious of all the STIs?

A
  • HIV/AIDS
391
Q

How is HIV transmitted?

A
  • through the transfer of body fluids (semen or vaginal fluids) during sexual intercourse
  • blood during blood transfusions/sharing of contaminated needles
  • milk from an infected mother who is breastfeeding her baby
392
Q

How does HIV affect the human body?

A
  • it attacks the body’s immune system
  • making it difficult for an infected person to fight off other diseases and infections
393
Q

How does Acquired Immune Deficiency Syndrome (AIDS) occur?

A
  • as the body’s immune systems gets weaker due to HIV, AIDS develops
394
Q

What are some symptoms of AIDS?

A
  • loss of appetite
  • rapid weight loss
  • diarrhoea lasting longer than a month
395
Q

What are some of the social consequences of HIV/AIDS?

A
  • treated badly by others
  • require others to spend more and more time caring for them
  • families suffer as they lose loved ones
  • families and communities cannot function as before as it is the young and middle-aged adults who would normally be supporting their families and communities who die from AIDS
396
Q

What are some of the economic consequences of HIV/AIDS in terms of education?

A
  • many young people do not have access to education and development that they need in order to become economically productive members of society because they are too busy caring for sick relatives or are sick themselves
397
Q

What are some of the economic consequences of HIV/AIDS in terms of family finances?

A
  • as families lose their breadwinners, there is financial hardship
398
Q

What are some of the economic consequences of HIV/AIDS in terms of the healthcare system?

A
  • the healthcare system is put under a lot of strain as their is often not enough money to provide the treatment needed for all the sick patients
399
Q

What are some of the economic consequences of HIV/AIDS in terms of local economies?

A
  • local economies suffer as there are not enough skilled workers to run businesses, schools and hospitals
400
Q

How is syphilis caused?

A
  • by a bacterium that enters the body through tears in mucous membranes in the genital areas
401
Q

How is syphilis spread?

A
  • by direct sexual contact with a person who has an active infection
  • by being passed on to a foetus during pregnancy
402
Q

How is syphilis diagnosed?

A
  • by blood tests that test for antibodies to the bacteria that cause syphilis
403
Q

What are the symptoms of the first stage of syphilis?

A
  • a small bump appears on the penis, vagina or cervix soon after infection
  • which gradually turns into a painless sore or ulcer that disappears after a few weeks
404
Q

What are the symptoms of the second stage of syphilis?

A
  • similar sores
  • a skin rash on other parts of the body
  • possible mild fever
405
Q

What are the symptoms of the third stage of syphilis?

A
  • (may occur 10 or more years after infection)
  • bacterium by this time will have invaded most parts of the body
  • will begin to cause damage to many organs such as the liver, bones, blood vessels and the nervous system
406
Q

How can syphilis be treated?

A
  • easily and successfully with antibiotics
407
Q

What can happen if syphilis is not treated?

A
  • it can be fatal
408
Q

How is gonorrhoea caused?

A
  • by a bacterium that lives and breeds in the moist, warm linings of the reproductive and urinary tubes and cavities
409
Q

How does gonorrhoea infection most often take place?

A
  • by direct sexual contact with a person who has an active infection
410
Q

Where does gonorrhoea most often start in women?

A
  • as an infection in the cervix
411
Q

What are the symptoms of gonorrhoea in women?

A
  • painful urination
  • pain during intercourse
  • a cloudy, yellowish vaginal discharge
412
Q

Why do women with gonorrhoea experience painful urination and/or pain during intercourse?

A
  • because the urethra and/or vagina is infected and inflamed by the bacteria
413
Q

What are the symptoms of gonorrhoea in men?

A
  • a yellowish urethral discharge, often with very painful urination
  • sometimes painful testicles
414
Q

How is gonorrhoea treated?

A
  • easily with antibiotics
415
Q

What happens if gonorrhoea is left untreated?

A
  • it could lead to serious complications
416
Q

What are the complications of untreated gonorrhea in females?

A
  • the infection can spread throughout the female reproductive tract
  • resulting in pelvic inflammatory disease
  • which can cause great damage to the reproductive organs
  • and may lead to infertility
417
Q

What are the complications of untreated gonorrhea in pregnant women?

A
  • there is an increased risk of an ectopic pregnancy, a miscarriage or premature birth
418
Q

What are the complications of untreated gonorrhea in childbirth?

A
  • during childbirth the bacteria may pass from a mother to her baby
  • which could lead to pneumonia
  • or a serious eye infection that can cause blindness in the baby
419
Q

When should one begin to question if they are infertile?

A
  • if they have been trying to conceive a baby for more than a year and have been unsuccessful
420
Q

What are some lifestyle choices that may affect one’s fertility?

A
  • stress
  • diet
  • age
  • alcohol
  • drugs
  • cigarettes
  • medicines
421
Q

Where is the problem found in most infertile men?

A
  • in the testis, the glands that produce sperm and testosterone
422
Q

What can damage the testis?

A
  • mumps
  • radiation or chemotherapy
  • trauma
  • surgery
423
Q

What can testicular damage lead to?

A
  • a low sperm count
  • poor sperm quality (sperm do not move well or are abnormally shaped)
424
Q

What can happen to the sperm ducts?

A
  • they can be blocked due to an infection
  • preventing the sperm from exiting during ejaculation
425
Q

How can male infertility be treated if the problem is that sperm counts are too low due to incorrect levels of male hormones?

A
  • LH and FSH hormone injections
  • this treatment is usually successful but may take a year or longer to bring back fertility
  • (this treatment is expensive)
426
Q

How can male infertility be treated if the problem is blocked sperm ducts?

A
  • surgical intervention can be attempted to clear blocked sperm ducts
427
Q

What are possible causes of female infertility?

A
  • problems with ovulation when viable eggs are not made
  • blocked oviducts that prevent egg and sperm from meeting
  • problems with the uterus (e.g. fibroids) which can prevent the implantation of a blastocyst
428
Q

What are fibroids?

A
  • lumps that develop from the myometrium which can prevent the implantation of a blastocysts
  • and subsequently, infertility
429
Q

What are the categories that female fertility treatments can be grouped into?

A
  • fertility drugs
  • surgical treatment
  • assisted conception
430
Q

How do fertility drugs generally work?

A
  • by causing the release of hormones that either trigger or regulate ovulation
431
Q

What kind of surgical treatments can be used to treat female infertility?

A
  • unblocking the fallopian tubes
  • removing fibroids
  • clearing up endometriosis
432
Q

What is endometriosis?

A
  • a disease in which tissue that normally grows inside the uterus grows outside the uterus
433
Q

What are the different techniques used in assisted conception?

A
  • artificial insemination
  • in vitro fertilisation (IVF)
  • gamete intra-fallopian transfer (GIFT)
  • intra-cytoplasmic sperm injection (ICPI)
  • surrogacy
434
Q

When is artificial insemination typically used?

A
  • if a man is unable to produce viable sperm
435
Q

How does artificial insemination work?

A
  • semen from a donor is inserted into the woman’s vagina at the time she is ovulating
436
Q

When is in vitro fertilisation (IVF) typically used?

A
  • if a woman is unable to produce viable eggs
437
Q

How does IVF work?

A
  • eggs are removed from the egg donor and fertilised by sperm from the woman’s partner, outside the body
  • the fertilised eggs are then placed in the uterus of the woman and left to implant in the endometrium
438
Q

How is the impregnation of the surrogate done?

A
  • either by artificial insemination from the man (commissioning father)
  • or implantation of an embryo from the woman (commissioning mother) through IVF
439
Q

What is a surrogate?

A
  • a woman who carries a baby on behalf of future parents who are medically unable to do so
440
Q

What is required by law in order for surrogacy to action to commence?

A
  • a high court application must grant its approval
441
Q

What is included in the documents required for the high court application?

A
  • psychological reports for surrogate mother and commissioning parents
  • medical report for commissioning parents with proof that they are unable to achieve a pregnancy for themselves
  • social worker’s report for surrogate and commissioning parents
442
Q

What may surrogacy not be done for?

A
  • may not be done for commercial gain
  • surrogate may only claim for loss of income and other expenses incurred as a direct result of the surrogacy/pregnancy
443
Q

What must the surrogate surrender?

A
  • any parental rights
444
Q

What is foetal alcohol syndrome (FAS)?

A
  • a pattern of birth defects, learning and behavioural problems affecting children whose mothers consumed alcohol during pregnancy
445
Q

How does FAS occur?

A
  • during pregnancy the alcohol freely crosses the placenta and causes damage to the developing embryo or foetus
446
Q

What are some classic physical features of FAS in new born babies?

A
  • short stature
  • low birth weight
  • poor weight gain
  • microcephaly
447
Q

What are some abnormalities in children with FAS that become evident as the children age?

A
  • poor attention span
  • poor motor skills
  • slow language development
  • hyperactivity disorder
  • learning disabilities or mental retardation
  • poor social skills
448
Q

Is there treatment for FAS?

A
  • no
  • children with FAS will remain mentally and socially defective all their lives