reproduction and development Flashcards
1
Q
gonads
A
organs where gametes are produced
2
Q
male gonads
A
testes
3
Q
female gonads
A
ovaries
4
Q
function of scrotum
A
contains testes and regulates temperature of testes
5
Q
testes
A
male gonad where sperm is produced and testosterone is secreted
6
Q
cremaster muscle
A
pulls testes in when temp is cold
7
Q
dartos muscle
A
contracts during cold and makes scrotum wrinkly to reduce SA so heat is not lost
8
Q
is dartos muscle relaxed or contracted in warm weather
A
relaxed
9
Q
in what cells of the testes does spermatogenesis occur
A
seminiferous tubules
10
Q
sertoli cells
A
cells of seminiferous tubules that help germ cells develop into spermatozoa
11
Q
germ cells
A
within seminiferous tubules and develop into spermatozoa
12
Q
interstitial cells of leydig
A
produce testosterone and androgens in response to lutenzing hormone
- adjacent to seminiferous tubules
13
Q
epidimis
A
storage center near end of testes for maturing spermatazoa that originated in the seminiferous tubules
14
Q
when spermatozoa entier the epydimis are they motile or non motile
A
NON-MOTILE
slowly gain motality after 2-3 months
- either ejaculated or broken down/absorbed from epydimis
15
Q
in the event of ejaculation, sperm will move from the epidimis to what?
A
vas defernes
16
Q
vas defernes
A
tube that runs between the epidimys and the ejaculatory duct
17
Q
ejaculatory duct
A
fusion of vas defernes with seminal vesicles
18
Q
seminal vesicles
A
generate liquid component of semen
- secrete fructose, vitamins, enzumes, other proteins needed for spermatozoa to live
19
Q
cowper’s glands
A
aka bulbourthral glands
- provide pre-ejaculation lubricant for urethra and neutralize acid
20
Q
ejaculation path
A
SEVEN UP
seminiferous tubukes
epidimis
vas deferens
ejaculatory ducts
urethra
penis
21
Q
sperm
A
haploid gamete with flagella (microtubules) that fertalize egg
22
Q
semen
A
alkaline liquid containing nutrients that carry sperm
23
Q
azoospermia
A
ejaculated semen that has no sperm in it, male infertility
24
Q
internal female genetalia
A
ovaries, fallopian tubes, uterus, cervix, vagina
25
external female genetalia
vulva
labia majora and minora , clit, vaginal opening
26
ovaries
female gonads where oogenesis occurs
contain follicles
also secrete estrogen and progesterone
27
ovarian follicles
each has an oocyte (immature egg cell)
28
what happens to ovarian follicle during menstral cycle
1 ovarian follicle releases a mature ovum into the fallopian tubes during ovulation
29
fallopian tubes
connect the ovaries to the uterus
- smooth muscle layer that carries out peristalsis and many cilia to move the egg from the ovaries to the uterus
30
uterus
where fetus develops during pregnancy
31
endometrium
inner epithelium of uterus
32
myometrium
middle layer of uterus containing smooth muscle
33
cervix
lower portion of uterus that connects to vaginal canal
- sperm must travel through cervix in order for fertilization to occur
34
spermatogensis
occurs in testes
- begins with spermatogonial stem cells and ends with mature spermatozoa
35
step 1 of spermatogenesis
spermatogonial cells either divide into descendent spermatogonial cells or differentiate into spermatogonia
36
spermatogonia
differentiate from spermatogonial cells and divide through mitosis into 2 primary spermatocytes
37
what sperm cells undergo meiosis
primary spermatocytes (2n) --> to become secondary spermatocytes (n)
38
secondary spermatocytes
haploid cells that undergo meiosis 2 to produce spermatids
39
result of meisosis in spermatogensis
4 haploid spermatids from each single primary spermatocyte
40
spermiogenesis
spermatids gain
1. formation of acrosomal cap
2. formation of tail
3. loss of excess cytoplasm
- end product: immature spermatozoa that are incapable of independent movement and are transferred to epididymis to undergo maturation
41
what is acrosomal cap
mature sperm cells contain this and facilitates the ability of sperm to fertalize egg
42
why must spermatids lose excess cytoplasm?
because sperm cells are very compact
43
structure of mature sperm cell
head --> contains DNA and sorrounded by acrosomal cap
mid-piece --> abundant mitochondria
tail --> motality
44
when does spermatogenesis occur during male lifetime?
during puberty and continues throughout life span
45
what is spermatogenesis highly sensistive to
temperature
46
oogenia
formed from primordial germ cells via gametogenesis
- ova develop through first 5 months of life
- develop into primary oocytes
47
primary oocytes
undergo mieosis 1 and become haploid secondary oocytes (n)
48
primary oocytes are frozen at prophase 1 because
it waits until puberty to commit to oogenesis
49
menarche
first puberty/ menstral cycle marks the resumption of oogenesis
- ovum is released and completes meiosis 1 , make 1 secondary oocyte and 1 polar body
50
meiosis 1 in oogenesis
secondary oocyte (receives majority of cytoplasm) --> undergoes meiosis 2
and polar body produced
51
meiosis 2 in oogenesis
secondary oocyte divides but is frozen at prophase 2 until fertalization occurs
- generates mature ovum and another polar body
52
what part of oogenesis occurs before birth
the oogonoim produces the primary oocyte (which will eventually under go meiosis 1) and is halted at the stage of the primary occyte until menarche (2n)
53
which part of oogenesis proceeds from puberty to menopause
primary oocyte undergoes mieosis to produce secondary oocyte and polar body
secondary oocyte undergoes meiosis 2 to produce polar body and ovum (only if fertalized)
54
fertilization
occurs in fallopian tubes
1. sperm cell must encounter secondary oocyte
55
corona radiata
layer of follicular cells sorrounding the secondary oocyte that sperm must pass through to fertalize
56
zona pelliculada
after passing through corona radiata, the sperm must pass through layer of glycoproteins between corona radiata and secondary oocyte
57
what occurs in the zona peliculada during fertilization
one of the glycoproteins binds with the sperm head and triggers the acrosome reaction (which allows the nucleus of the sperm to enter the egg)
58
cortical reaction
process during fertilization where the cross-link between the glycoprotein and acrosomal head that prevents fertilization by another sperm cell
59
zygote
fertilized ovum merges with haploid sperm cell to produce diploid zygote in the fallopian tube, must travel to uterus for further development
- defined by unicellularity
60
ectopic pregnancy
if the zygote does not travel from the fallopian tubes to the utereus , leads to nonviable fetus
61
cleavage
zygote undergoes mitotic cell divisions as it travels to uterus
62
embryo
multicellular fertilized zygote
63
morulla
once zygote has cleaved into a mass of 16 cells by 3-4 days after fertilization, tight ball
64
blastocyte
same as blastula
by 4-5 days after fertilization
there becomes a cavity within the morula
IMPLANTS INTO THE ENDOMETRIUM
65
implantation
multi-stage process that involves close communication between growing embryo and uterine tissue
- placenta begins to form from trophoblast and chorion and amnion
66
gastrula
from blastocyt
1. ectoderm
2. endoderm
3. mesoderm
67
ecotderm
skin, central nervous system, lining of mouth, anus, nostrils,
68
neurulation
formation of nervous system through ectoderm
69
first step of neurulation
formation of the notochord --> induces the formation of neural plate
70
neural tube
forms central nervous system
71
neural crest cells
peripheral nervous system
72
mesoderm
forms musculature, gonads, connective tissue (blood bone cartilage), kidneys, adrenal cortex
73
endoderm
interior lining of body, pancreas, liver, lining og GI , urinary bladder, urethra, lungs
74
major process of first trimester
organogenesis
75
placenta
supplies fetus with nutrients during pregnancy and allows gas exchange between mother and fetys
- secretes HCG
76
fetal hemoglobin
higher affinity for oxygen than regular hemoglobin
77
SRY gene
determines male sex during fetal development and produce testes
78
wolfian and mullerian duct
precursor structures that form into male structures after SRY male differentiation
wolfian-- epididymis, vas defernes,
mullerian - lost
79
parturition
childbirth
80
which hormone induces labor contractions
oxytocin (positive feedback loop)
81
LH in males
causes production of testosterone in interstitial cells of leydig
82
LH in females
causes ovaries to produce estrogen
83
FSH in females
maturation of ovarian follicule
84
FSH in men
spermatogenesis in seminiferous tubules
85
ovarian cycle
follicular phase then ovulation then luteal pjase
1 ovum is released every cycle
86
follicular phase
follicle matures and releases the egg during ovulation
87
luteal phase
refers to what happens after the egg is released , follicle is tranformed into corpus luteum
88
corpus luteum
secretes progesterone and helps maintain uterine lining , decays at end of the cycle
89
menstration
right before follicular phase when passed uterine lining is shed
90
proliferative phase
uterine endometrium is built up
91
what hormone dominates at begining of follicular stage
FSH
estrogen gradually increases
92
lh surge
induces ovulation and formation of corpus luteum
93
luteal phase
increased progesterone
94
no impantation
negative feedback of progesterone on LH and corpus luteum disintegrates , progesterone not being produced
95
how is corpus luteum maintained during implantation
embryo secretes HCG to keep sustained progesterone levels
96
what hormones can placenta secrete
estrogen and progesterone (by 2nd tri) so no longer need hcg from embryo
