Urogenital System Flashcards Preview

ANAT1003 test 2 > Urogenital System > Flashcards

Flashcards in Urogenital System Deck (106):
1

what does the urinary system comprise of?

kidneys, ureter, bladder and urethra

2

what is the function of the urinary system?

to eliminate water from the body, regulate blood volume and pressure, control levels of electrolytes and metabolites and regulate blood pH

3

through what does the blood enter the kidneys?

renal arteries

4

though what does blood exit the kidneys?

renal veins

5

what filters blood in the kidneys?

nephrons

6

through what does urine enter the kidneys?

ureters

7

through what does urine exit the kidneys?

urethra

8

which germ layer forms the majority of the urinary system?

intermediate mesoderm

9

when are pronephric ducts formed?

4th week

10

where are pronephric ducts formed?

cervical region

11

what do pronephric ducts induce?

adjacent mesenchyme to condense into pronephroi

12

what do pronephroi form in fish and amphibians?

functional nephrons

13

in what direction does the ductal system extend?

caudal

14

what it the mesonephros?

the first functional kidney in the early embryo

15

when do the phenephric ducts begin to degenerate?

by the 25th day, but not until they extend caudally to form the mesonephric duct

16

what is the adult kidney called?

metanephric kidney

17

where are human kidneys found?

in the paravertabral gutter, on either side of the abdomen

18

which kidney is slightly lower than the other?

the right kidney is slightly lower than the left

19

what is located on top of each kidney?

adrenal gland

20

how many nephrons does the average kidney have?

1 million

21

what happens in the glomerulus and bowmans capsule?

blood pressure drives water and solutes out of the blood and into the bowmans capsule

22

which parts of the urinary system are formed of endoderm?

bladder and urethra

23

what does the intermediate mesoderm form during embryonic folding?

a longitudinal mass called the urogenital ridge

24

what does the urogenital ridge form?

the urinary and genital systems

25

what is the nephrogenic cord?

the part of the urogenital ridge that forms the urinary system

26

what is the gonadal ridge (or genital ridge)?

the part of the urogenital ridge that forms the genital system

27

what are the names of the three different kidneys that are formed during development?

pronephros, mesonephros and metanephros

28

what do the nephric ducts fuse with and when?

the clocea on day 26

29

what is the clocea?

an endodermal sac that links to both the digestive tract and the allantois

30

what are pronephroi?

rudimentary and non-functional nephrons

31

what induces adjacent mesenchyme to condense into mesonephroi?

the mesonephric duct

32

when does the metanephroi (permenant kidney) begin to form?

5th week

33

when do the mesonephroi become functional?

end of the 11th week

34

what happens to urine in the embryo?

it is secreted into the amniotic cavity where it contributes to amniotic fluid

35

what acts on the nephric duct to induce the formation of the ureteric bud?

the metenephric mesenchyme

36

what is another name for the nephric duct?

metanephric diverticulum

37

what is the main inductive signal involved in forming the metanephric kindey?

Glial-Cell-Derived Neurotrophic Factor (GDNF)

38

what signals does the mesenchyme release?

BMP4

39

what does BMP4 ensure?

that only a single ureteric bud is formed by each nephric duct

40

caudal mesonephric ducts sprout ureteric buds that grow into what?

a metanephric blastula

41

what happens to the ureteric ducts?

they bifurcate and induce cranial and caudal lobes in the metanephric blastula

42

the tip of each collecting duct induces the blastemal cap to form what?

a nephric vesicle

43

what will the nephric vesicle form?

bowmans capsule, proximal and distal convoluted tubules and the loop of henle

44

what are the testes?

paired organs that lie outside of the pelvis in scrotal sacs

45

what to testes produce?

sperm and male hormones

46

what is the epididymus?

tightly coiled tubes adjacent to the testes

47

what does the epididymus do?

acts as a maturation and storage vesicle for sperm

48

what is the vas deferens?

a long, thin tube that carries sperm from the epidiymus to the penis

49

where is the seminal vesicle?

it is attached to the vas deferens along the side of the bladder

50

what does the seminal vesicle do?

it produces seminal fluid which nourishes the spermatozoa

51

what is the prostate?

it surrounds the ejacultory ducts at the base of the urethra below the bladder. it produces seminal fluid which nourishes the spermatozoa

52

what are the ovaries?

small paired organs located near the lateral walls of the pelvic cavity

53

what do the ovaries produce?

ovum and female hormones

54

what are the fallopian tubes?

paired oviducts that lead from the ovaries to the uterus

55

where does fertilisation occur?

in the fallopian tubes

56

what is the uterus?

a pear shaped muscular organism that provides nutritional support and mechanical protection for the implanted embryo. contractions of the uterus are important for pushing the fetus out during birth

57

what does PGC stand for?

primordial germ cells

58

when are the PGCs formed and where?

during gastrulation in week 2 in the caudal epiblast layer

59

where do the PGCs migrate to?

the gonadal ridge via the umbilical cord, gut and dorsal mesentery

60

where is the gonadal ridge?

in the intermediate mesoderm between the forelimb and hindlimb

61

what are gonads?

testes in males and ovaries in females

62

what do PCGs promote the development of?

gonads

63

what does the gonadal ridge form?

the somatic cells of the gonad

64

what do the gonads proliferate to form?

primitive sex cords

65

what happens to males sex cords?

they grow into the gonadal ridge to form the testis cords

66

what do the testis cords form?

seminiferous tubules composed of sertoli cells

67

what does the mesenchyme form (males)?

leydig cells

68

what are leydig cells responsible for?

testosterone production

69

what does the anti-mullerine hormone do?

cause degeneration of the mullerian duct

70

what is turners syndrome?

a sterile female - XO

71

what is klinefelters syndrome?

sterile male - XXY

72

how many base pairs does the Y chromosome have?

59million

73

how many protein coding genes does the Y chromosome have?

45-53

74

which arm of the Y chromosome contains the SRY gene?

the short arm

75

what does the SRY gene specify?

testes development and therefore the male sex

76

what regions contain genes that are shared with the X chromosome?

the pseudoautosomnal region

77

what is SRY?

a DNA binding protein/transcription factor

78

what proteins does SRY encode?

proteins belonging to the SOX family

79

what do mutations in SRY cause?

swyer syndrome

80

what is swyer syndrome?

female anatomy but cannot produce female hormones, therefore no secondary sexual characteristics

81

in the genital ridge, what does SRY activate the transcription of?

SOX9

82

what is SOX9?

a closely related transcription factor that drives testes development

83

in the absence of SRY, what happens?

WNT4 is transcribed in the genital ridge and ovarian development takes place

84

what is physical appearance determined by?

hormones secreted by the gonads

85

what drives the development of male characteristics?

testosterone from testes

86

what does AMH induce?

the degeneration of mullerian ducts and the absence of the female reproductive tract

87

in the absence of testosterone and AMH, what happens?

mesonephric ducts degenerate and mullerian ducts differentiate into female reproductive tract

88

what does the development of female characteristics require?

the absence of testosterone and the production of oestrogen

89

what is congenital adrenal hyperplasia?

XX individuals have more masculine genitals than normal

90

what causes congenital adrenal hyperplasia?

an autosomal recessive mutation in genes that encode enzymes responsible for the synthesis of adrenal hormones (cortisol and aldosterone). leads to increase in level of testosterone.

91

what do female sex cords do?

they remain in the cortex of the gonodal ridge and form ovarian cords

92

what do ovarian cords form?

granulosa (follicle) cells that surround the developing ova

93

what does mesenchyme form (female)?

Thecal cells

94

what are thecal cells responsible for?

oestrogen production

95

what does the mullerian duct form in females?

the caudal ends of the mullerian ducts fuse to form oviducts, uterus and the upper third of the vagina

96

what makes up the lower two thirds of the vagina?

endoderm

97

how many females have a uterine defect?

1%

98

what is the most common uterine defect?

a seperated uterus

99

how does the male genitalia form?

urogenital folds fuse and genital tubercle elongates to form the penis. invagination of the ectoderm covering the glans forms distal urethra. labioscrotal folds form the scrotum.

100

how does the female genitalia form?

genital tubercle bends inferiourly to form the clitoris. urogenital folds remain separated to form labia minora. labiosacral folds form the labia majora.

101

when is primary sex determined?

sex chromosome carried by sperm

102

which sex forms in the absence of SRY?

female

103

what is 5-a-reductase deficiency?

when a genetically male (XY) infant is born with indifferent genitalia

104

what causes 5-a-reductase deficiency?

autosomal recessive mutations in the gene encoding isofrom 2 of 5-a-reductase

105

what is androgen insensitivity syndrome?

genetically male (XY) infant with prenatal feminisation, ranging from ambiguous genitalia to full female appreance

106

what is androgen insensitivity syndrome caused by?

a recessive mutation in androgen receptor gene