The Reproductive System Flashcards
(86 cards)
1
Q
which pair of chromosome is the chromosomal sex determined by?
A
the 23rd pair of chromosomes
2
Q
what does XX mean?
A
female
3
Q
what does XY mean?
A
male
4
Q
which only chromosome can the ova carry?
A
only the X chromosome
5
Q
which chromosomes can sperm carry?
A
either X or Y
6
Q
what can a mutation in the X chromosome cause?
A
sex-linked (X-linked) disorders
7
Q
what are carriers?
A
when females carry a diseased allele on the X chromosome, but do not exhibit the disease
8
Q
are most X-linked disorders recessively or dominantly inherited?
A
recessively
9
Q
does the X or Y chromosome contain more genetic information?
A
X chromosome
10
Q
what is a notable gene on the Y chromosome?
A
SRY (sex determining region Y)
11
Q
what does the SRY gene initiate?
A
initiates testis differentiation and the formation of male gonads
12
Q
what happens in the absence of Y chromosome?
A
all zygotes will be female
13
Q
what happens in the presence of a Y chromosome?
A
a zygote will be male
14
Q
in males, what do the primitive goands develop into?
A
the testes
15
Q
what are the two functional components of the testes?
A
the seminiferous tubules (where sperm is produced) and the interstitial cells of Leydig (where testosterone and other androgens are produced)
16
Q
where are sperm produced?
A
in the seminiferous tubules
17
Q
what are sperm nourished by?
A
the Sertoli cells in the seminiferous tubules
18
Q
what do the cells of Leydig secrete?
A
testosterone and other male sex hormones (androgens)
19
Q
where are the testes located?
A
in the scrotum
20
Q
what is the scrotum?
A
an external pouch that hangs below the penis
21
Q
why is the scrotum below the penis?
A
to allow it to maintain a temperature 2-4 degrees lower celsius than the body
22
Q
what can raise and lower the testes?
A
the layer of muscle around the vas deferens
23
Q
why might the muscle around the vas deferens raise or lower the testes?
A
to maintain the proper temperature for sperm development
24
Q
where are the sperm passed to after they’re formed in the seminiferous tubules?
A
they are passed to the epididymis
25
what happens in the epididymis?
the flagella gain motility, and they are then stored until ejaculation
26
where does the sperm travel from and to during ejaculation?
- sperm travel through the vas deferns and enter the ejaculatory duct at the prostate gland
- the two ejaculatory ducts fuse to form the urethra, which carries sperm though the penis, as they exit the body
27
28
is sperm the only fluid as they pass through the reproductive tract during ejaculation?
no, it is mixed with other seminal fluids
29
what do the seminal vesicles contribute to the sperm during ejaculation?
they contribute fructose to nourish the sperm
30
what does the prostate gland contribute to sperm during ejaculation?
gives the sperm mild alkaline properties so the sperm can survive in the female reproductive tract
31
what do the bulbourethral (Cowper’s) glands contribute during ejaculation?
produce a clear fluid that cleans out any remnants of urine and lubricates urethra during sexual arousal
32
what is semen?
sperm mixed with other seminal fluid
33
what is spermatogenesis?
the formation of haploid sperm through meiosis
34
where does spermatogenesis occur?
int he seminiferous tubules
35
what is spermatogonia?
the diploid stem cells in males
36
what are the correct stages of spermatogenesis?
diploid primary spermatocytes -> haploid secondary spermatocytes -> haploid spermatids -> mature spermatozoa
37
what are the three parts of a sperm cell?
head (contains the genetic material), midpiece (generates ATP from fructose), flagellum (for motility)
38
why is the midpiece of the sperm cell filled with mitochondria?
to generate the energy for swimming through the female reproductive tract
39
what is the sperm head covered by?
a cap known as the acrosome
40
what is the acrosome necessary for?
necessary to penetrate the ovum
41
START WITH FEMALE REPRODUCTIVE
42
what are the gonads in the female reproductive system known as?
the ovaries
43
what do the ovaries produce?
estrogen and progesterone
44
where are the ovaries located in?
the pelvic cavity
45
what does each ovary consist of?
each consists of a thousand follicles
46
what are follicles?
multilayered sacs that contain, nourish, and protect immature ova (eggs)
47
how many eggs per month is ovulated?
one egg
48
where is the egg ovulated into?
the peritoneal sac, which lines the abdominal cavity
49
where does the ovulated egg go into after the peritoneal sac?
the fallopian tube, which is lined with cilia got propel the egg forward
50
what is the external part of the female genital organs?
the vulva
51
what is oogenesis?
the production of female gametes
52
is there an unending supply of oogenia in a female?
no; all the oogenia a female will ever have are formed during fetal development
53
what are the oogenia already considered by birth?
primary oocytes
54
what is menarche?
the first menstrual cycle
55
what happens to the primary oocyte per month after menarche?
one primary oocyte per month will complete meiosis I, producing a secondary oocyte and polar body
56
how many layers are the oocytes surrounded by?
two layers
57
what are the two layers of the oocytes?
zona pellucida and corona radiata
58
which hormone is restricted prior to puberty?
the hypothalamus restricts the production of gonadotropin-releasing hormone (GnRH)
59
what happens at the start of puberty to GnRH?
the hypothalamus releases pulses of GnRH
60
what does the release of GnRH by the hypothalamus at the start of puberty trigger?
triggers the anterior pituitary gland to synthesize and release FSH and LH
61
what does the presence of Y chromosome lead to during the fetal period?
leads to the production of androgens, resulting in male sexual differentiation
62
is androgen production low during infancy and childhood for males?
yes
63
when does testosterone increase dramatically?
during puberty
64
which hormone stimulates the Sertoli cells and triggers sperm maturation?
FSH
65
which hormone causes the interstitial cells to produce testosterone?
LH
66
does testosterone result in development of secondary sexual characteristics?
yes
67
what are the secondary sexual characteristics?
facial/axillary hair, deepening of voice, increased muscle and bone mass
68
does testosterone exert positive or negative feedback on hypothalamus and anterior pituitary?
negative feedback
69
why does testosterone exert negative feedback on hypothalamus and anterior pituitary?
to keep production within an appropriate range
70
what does FSH lead to in females?
production of estrogen
71
what does estrogen result in for females?
secondary sexual characteristics
72
what are the secondary sexual characteristics for females?
breast growth, widening of hips, changes in fat distribution
73
FSH and LH in females and males
LH leads to production in testosterone in males & FSH leads to production in estrogen in females
74
what hormone leads to thickening of lining of the uterus (endometrium)?
estrogen
75
what is the progesterone secreted by?
the corpus luteum
76
what is the corpus luteum?
the remains of the ovarian follicles following ovulation
77
what is estrogen involved in regarding the endometrium?
in the initial thickening of the endometrium
78
what is progesterone involved in regarding the endometrium?
the development and maintenance of the endometrium
79
80
what are the four stages of the menstrual cycle?
follicular phase, ovulation, luteal phase, menstruation
81
what happens in the follicular phase?
- begins when menstrual flow begins
- GnRH increases in response to decreased estrogen and progesterone
- higher GnRH leads to increased FSH and LH
- FSH and LH develop and secrete ovarian follicles
- ovarian follicles produce estrogen
- estrogen has negative feedback effects and causes GnRH, FSH and LH to decrease
- estrogen stimulates regrowth of endometrial lining
82
what happens during ovulation?
- developing follicles secrete higher and higher concentrations of estrogen
- estrogen reaches a threshold and results in positive feedback
- increases GnRH, FSH and LH
- LH induces ovulation (release of ovum from ovary into peritoneal cavity)
83
what is the luteal phase?
- LH causes ruptured follicle to form the corpus luteum
- corpus luteum secretes progesterone
- progesterone maintains the endometrium for implantation
- progesterone levels begin to increase, while estrogen levels remain high
- high levels of progesterone cause negative feedback on GnRH, FSH and LH, preventing ovulation of multiple eggs
84
what happens during menstruation?
- corpus luteum loses its stimulation from LH
- progesterone levels decline
- the loss of high levels of estrogen and progesterone removes block on GnRH so the next cycle can begin
85
what happens during pregnancy?
- resulting zygote will develop into blastocyst that will implant in uterine lining and secrete hCG
- stimulates LH receptors to maintain the corpus luteum
- hCG critical during first trimester because estrogen and progesterone (secreted by corpus luteum) keep uterine lining in place
- hCG declines by second trimester because placenta has grown sufficiently to secrete enough progesterone and estrogen by itself
- high levels of estrogen and progesterone serve as negative feedback on GnRH secretion
86
what happens during menopause?
- with aging, ovaries become less sensitive to FSH and LH
- results in ovarian atrophy
- as estrogen and progesterone levels drop, endometrium also atrophies and menstruation stops
- since the negative feedback on FSH and LH is removed, blood levels of FSH and LH rise
