lecture 19 - genital system Flashcards
(85 cards)
1
Q
reproduction
A
process which new individuals of a species are porduced and genetic material is passed from generation to generation
2
Q
chromatin
A
uncondensed genetic material
3
Q
somatic cells
A
diploid
23 pairs of chromosomes = 46
4
Q
paired chromosomes are
A
homologous
contains same genes in the same order
5
Q
sex chromosomes are
A
either X or Y
male = XY
female = XX
6
Q
the gene on the Y chromosome initiates development of
A
of testes and the release of test during dvelopment
7
Q
diploid
A
2 sets of chromosomes
8
Q
gamete
A
haploid cell
23 chromosomes
9
Q
ovaries and testes produce haploid gametes at
A
sexual materity
10
Q
is meiosis 1, homo chromosomes:
A
homologous chromosomes separate
11
Q
in meiosis 2, sister chromatids:
A
separate
12
Q
fertilization
A
union and fusion of gametes
13
Q
zygote
A
contains one set of chromos from each parent
diploid
14
Q
zygote divides by:
A
mitosis
15
Q
gonads function
A
produce gametes and secrete hormone
16
Q
ducts
A
store and transport gametes
17
Q
accessory sex glands general function
A
produce substances ot support gametes
18
Q
male ducts
A
epididymis, ductus deferens, ejaculatory duct, urethra
19
Q
male accessory glands
A
seminal gland, prostate, bulbourethral gland
20
Q
male supporting structures
A
scrotum, penis
21
Q
raphe
A
externally separates scrotum into lateral portions
22
Q
scrotal septum
A
internally divides scrotum into two compartments
23
Q
cremaster muscel
A
skeletal muscel that moves testes close to body
24
Q
dartos muscle
A
smooth muscle that causes scrotum to become tight to lessen surface area
25
required temp for sperm production
2-3 lower than body, 34-35 ish
26
how is ideal temp for sperm porduction reached (2)
testes located outside of body cavities
contraction of scrotal muscle fibres to elevate and decreases surface area of scrotum during cold exposure
reverses in heat
27
tunica vaginalis
partially covers testes
28
tunica albuginea
white fibrous capsule surroudning testes
29
tunica albuginea function
divides testes into 2-300 lobules
30
lobules
contain 1-3 seminiferous tubules where sperm is produced
31
spermatogenesis
process of sperm prodcution
32
2 cell types in seminiferous tubules
spermatogonia
nurse cells
33
spermatogonia
sperm forming cells - 2n
34
nurse cells
supportive cells that secrete inhibin, and regulate test and FSH
35
interstitial endocrine cells
located in spaces between seminiferous tubules
secrete testosterone
36
waht do spermatogonia develop from
primordial stem cells
37
what forms blood testes barrier
nurse cells joined by tight junctions
38
function of blood testes barrier
protect developing sperm from immune response
39
nurse cells function
nourish sperm cells, release sperm into lumen, provide fluid for transport, secrete inhibin
main: regulate FSH and Test activity
40
length of spermatogenesis
65-75 days
41
in spermatogenesis, spermatogonia undergo _______, what happens
mitosis
some stay as stem cells and others differentiate into primary spermatocytes (2n)
42
in spermatogenesis, primary spermatocytes undergo ________, waht happens
meiosis 1
secondary spermatocytes are formed (n)
43
in spermatogenesis, secondary spermatocytes undergo _____, what happens
meiosis 2
spermatids are formed (n)
44
spermiogenesis
maturation of spermatids into sperm (n)
cells elongate, develop acrosome/flagella, mitochondria multiply
45
spermiation
sperm are released from connections to nurse cells
sperm cannot swim as this point, fluid secreted by the nurse cells push the sperm to the lumen and epididymis
46
cytoplasmic bridges
link spermatids together (incomplete cytokinesis)
47
head of a sperm contains
nucleus
- 23 chromos
acrosome
- has enzymes to help penetrate and fertilize secondary oocyte
48
tail of sperm contains:
neck
- contains centrioles
middle piece
- mitochrondria for ATP and movement
principal and end pieces of tail
49
hormonal control of spermatogenesis
puberty -> hypothalamus releases gonadotropin releasing hormone -> ant pituitary release LH and FSH
50
LH function in males
stimulates interstitial endocrine cells to secrete testosterone
51
FSH function in males
act on nurse cells to promote secretion of androgen binding protein
indirectly stimulates spermatogenesis
(FSH receptors are located on nurse cells)
52
inhibin function males
secreted by nurse cells to inhibit FSH
53
dihydrotestosterone (DHT) and testosterone both have
the same androgen receptors
54
effects of androgens (test, dihydrotestosterone)
(before birth/puberty, what they regulate, and stimulate)
before birth
- stimulate development of male reproductive system
at puberty
- control growth, development, functioning of sex organs, male secondary sex features
regulate
- male sexual behavior/drive
stimulate
- protein synthesis, bone and muscle mass increase
55
feedback loop for testosterone
receptor
- hypothalamus detect blood levels
input
- decreased GnRH
control centre
- anterior pituitary gonadotrophic cells
output
- decreased LH in blood
effectors
- interstitial endocrine cells secrete less test
56
what pushes sperm along the duct of testes system
pressure generated by the fluid from nurse cells
57
duct of testes system (6)
seminiferous tubules lumen
straight tubules
rete testes
efferent ductules
duct of epididymis
ductus deferens
58
epididymis
site of sperm maturation (14 days)
- sperm acquire motility and ability to fertilize oocyte
propels sperm to ductus deferens
sperm may remain here for storage for months, can be ejaculated or reabsorbed
59
ductus deferens
long duct that loops around ureter
stores sperm and propels sperm from epididymis to prostatic urethra during ejaculation
60
ejactulation is faciliated by
peristalsis of 3 smooth muscle layers
61
vasectomy
removal of a portion of the ductus deferens
- incision in posterior scrotal sac
sperm is still produced but cannot reach exterior
testosterone remained unchanged
62
spermatic cord
supporting structure that ascends out of scrotum
63
ejaculatory ducts
formed by union of duct from seminal gland and ampulla of ductus deferens
terminates in prostatic urethra
ejects sperm and secretions from seminal glands into urethra before ejaculation
64
urethra
long passageway for urine and semen
3 parts
- prostatic
- membranous
- spongy
ends at external urethra orifice
65
what secretes most of the liquid portion of semen
accessory glands
66
seminal glands
pair of pouch like organs
67
seminal glands secrete (3)
alkaline fluid
fructose
substances that help with motility and clotting proteins
68
prostate
donut shaped organ surrounding prostatic urethra
69
prostate secretes (4)
citric acid
proteolytic enzymes
seminal plasmin
acid phosphatase
70
citric acid from prostate function
ATP production in sperm
71
proteolytic enzymes from prostate function
liquefy coagulated semen
72
seminal plasmin from prostate function
antibiotic
73
bulbourethral glands
pea sized glands inferior to prostate
74
BB glands secrete (2)
alkaline fluid
mucus
75
semen
mixture of sperm and seminal fluid
76
sperm is slightly alkaline
7.2-7.7
77
penis parts
root body glans penis
78
body of penis
made of 3 masses of erectile tissue
2 corpora cavernosa
corpus spongeosum
79
corpora cavernosa function
maintaining erection
80
corpus spongiosum function
contains spongy urethra and keeps it open during ejectulation
81
how is an erection maintained
spongy structures of blood sinuses lined by endothelial cells and surrounded by smooth muscel fill with blood
nitric oxide vasodilates arterioles
increased blood flow compresses veins, trapping blood
82
an erection is a ______ refelxe
parasympathetic
83
ejaculation is a ____ reflex
parasympathetic, controlled by lumbar spinal cord
84
how does ejaculation work
peristalsis propels semen to spongy urethra
85
after ejactulation
arterioles supplying erectile tissue constrict and veins and unblocked, allowing blood to drain
