Chapter 20: Reproduction
At the end of a cycle in which fertilization has occurred: ______ & _______ secretion is suppressed
FSH and LH secretion is suppressed
chromosome pairs 1-22 are _____
autosomal chromosomes
GnRH is secreted from the ____
hypothalamus
where are follicles and what do they contain
in ovaries, contain eggs
where are sertoli cells?
in the seminiferous tubules
where are seminiferous tubules?
in the testes
after mitosis ends for oogonia in females, the 1st meiotic division creates ____
primary oocytes (2N)
spermatozoa is the plural of
sperm
semen is composed of ____
sperm and fluids from the testes
when duplicated chromatids are separated into daughter cells they become _______
spermatids (N)
what are sertoli cells incharge of?
spermatogenesis and secretion of inhibin
movement of semen into urethra is stimulated by ________ nerves
sympathetic
what are the gonadal steroids?
testosterone, estradiol, and progesterone
what does homologous chromosomes mean?
they look like each other and contain similar genes except for the sex chromosomes
what is the pathway of sperm after spermatogenesis in the seminiferous tubules ?
- moves from tubules into rete testis - then into the efferent ductules - then to epididymis - then into vas deferens
what are the erectile tissues?
1) corpus spongiosum 2) corpa cavernosae
what is the 3-hormone sequence ?
1) hypothalamus secretes GnRH 2) anterior pituitary gland secretes FSH and LH 3) gonads stimulated to secrete sex hormones and undergo gametogenesis
what are the stages of spermatogenesis?
1) mitosis 2) first meiotic division 4) second meiotic division 5) spermiogenesis
at the time of fertilization, the _____ at the head of an individual sperm releases enzymes that allow it to enter the ova
acrosome
______ is the growth of muscles and other structures
anabolism
where do gonadotropic hormones come from
anterior pituitary gland
the fluid filled cavity of a graafian follicle is called an
antrum
when does mitosis of oogonia end for females?
at 7 months of gestation
where are leydig cells located?
between seminiferous tubules
the uterus narrows to form the
cervix
sex hormones are ______ based
cholesterol based
spermatogonia are _____ until meiosis
diploid (2N)
the ____ is the innermost layer of the uterus, contains epithelial layers that are sloughed off during menstruation
endometrium
what do the ovaries synthesize and secrete?
estrogen, progesterone, and inhibin
where is the usual site of fertilization?
fallopian tubes
true or false: Meiosis II of spermatogenesis results in the formation of secondary spermatocytes.
false
x or y comes from the
father
XX
female
how does the ovum move from the ovaries into the oviduct?
fimbrial contractions
after _______ homologous chromosomes separate into two daughter cells called secondary spermatocytes
first meiotic division
During ovulation, the _____ ruptures and the oocyte enters the uterine tube; later, the empty follicle undergoes structural and biochemical changes and a _____ is formed.
follicle; corpus luteum
_____ are the sperm and egg
gametes
_____ is spermatogenesis and oogenesis
gametogenesis
what are the functions of the male gonads (testes)?
gametogenesis (spermatogenesis)
during puberty gonads secrete more sex steroid hormones due to stimulation by ____
gonadotropic hormones (FSH and LH)
______ are the testis and ovary
gonads
sex hormones secreted from
gonads
continued growth of secondary follicle results in a
graafian follicle
primary oocytes are surrounded by ____
granulosa cells
each gamete receives 23 chromosomes making them _____
haploid
Puberty in humans is the result of changes in the ___________, which result in an increased secretion of _________, which then stimulates an increased secretion of luteinizing hormone.
hypothalamus; GnRH
erection occurs when parasympathetic axons
increase blood flow into corpora cavernosae and corpus spongiosium
what does FSH do in the male reproductive system?
initiates spermatogenesis and secretion of inhibin by sertoli cells in seminiferous tubules
the _____ define the vestibule into which opens to the vagina and urethra
labia minora
XY
male
what process produces mature germ cells or gametes in the gonads ?
meiosis
the zygote goes through the process of ______ as it grows into an adult
mitosis
OOgonia undergo ____ division during fetal life
mitotic
how often does an ovary release an ovum
monthly
X comes from the
mother
the _____ is the middle layer of the uterus that is thick and made of smooth muscle
myometrium
follicle growth in a female is called
oogenesis
production of haploid gametes in females is called _____
oogenesis
what is gametogenesis called in females
oogenesis
where do germ cells become spermatogonia
outermost region of seminiferous tubules
what are the layers of the uterus from outermost to innermost?
outter : perimetrium middle: myometrium inner: endometrium
what are the female gonads ?
ovaries
the ____ is the outermost layer of the uterus, includes connective tissue and line the pelvic cavity
perimetirum
what do spermatogonia become after mitotic division ?
priary spermatocytes (2N)
_______ are primary oocytes surrounded by granulosa cells
primordial follicles
after ______ chromatids are separated into spermatids (N)
second meiotic division
some primary follicles grow and develop more to become a ______
secondary follicle (which becomes a graafian follicle)
During spermatogenesis, the first cells to become haploid are the _____.
secondary spermatocytes
what do leydig cells do?
secrete testosterone
Spermatogenesis occurs in the _____.
seminiferous tubules
where does spermatogonia occur?
seminiferous tubules
The testes consist of two compartments: the _____, where spermatogenesis occurs, and the _____, which contains the testosterone-secreting Leydig cells
seminiferous tubules; interstitial tissue
_______ cells in the tubular wall support spermatogenesis and protect developing sperm in the seminiferous tubules
sertoli cells
what is the site of spermatogenesis within the seminiferous tubules?
sertoli cells
where is inhibin secreted from?
sertoli cells
pair 23 is the _____
sex chromosomes
germ cells during early embryonic development become ____
spermatogonia
what occurs during mitosis regarding spermatogenesis
spermatogonia duplicate themselves via mitotic division (turning into primary spermatocytes 2N)
The correct sequence of cells in spermatogenesis is _____.
spermatogonium -> primary spermatocyte -> secondary spermatocyte
________ is the process of spermatids transforming into spermatozoa (N)
spermiogenesis
what does LH do in the male reproductive system?
stimulates Leydig cells to secrete testosterone
chromatids are
strands of DNA
how do erectile disfunction drugs like Viagra and Cialis help?
they increase cGMP to promote vasodilation
what do the fallopian tubes do?
transport released ovum plus some follicular cells via ciliary action and smooth muscle contractions
true or false: During spermatogenesis, spermatids differentiate into spermatozoa.
true
what are the different names of sperm as it goes through spermatogenesis?
1) spermatogonia 2) primary spermatocyte 3) secondary spermatocytes 4) spermatids 5) spermatozoa (sperm)
each chromosome pair contains ____ homologous chromosomes
2
how many primary oocytes are there at birth?
2 million
how many pairs of chromosomes does an individual have in each cell?
23 pairs
how many sperm are produced each day
300 million
how many oocytes are actually ovulated in a lifetime?
400
how many oocytes survive by puperty
400,000
a cell that is diploid contains _____ chromosomes
46
a fertilized egg (zygote) has how many chromosomes?
46
how many chromosomes are there total in each cell?
46
what does diploid (2N) mean
46 chromosomes
oogenesis is stimulated by ____
FSH
what are the gonadotropic hormones?
FSH & LH
Ovulation is most directly stimulated by a surge in the secretion of:
LH
secondary spermatocytes contain ______ chromosomes
23
what are the stages of oogenesis?
- primary follicle -secondary follicle -graafian follicle -first meiotic division -second oocyte
the second meiotic division is not completed until _____
fertilization