20.1 General aspects of reproductive physiology Flashcards
True or false: The reproductive system plays a role in homeostasis
false
Reproductive capability depends on intricate relationships among………
the hypothalamus, anterior pituitary, reproductive organs, and target cells of the sex hormones
what makes up the reproductive system?
gonads, reproductive tract, accessory sex glands (differ in males and females)
Reproduction depends on the union of
male and female gametes to form new a individual with a full unique set of chromosomes.
Gametes are
haploid (have half the set of chromosomes)
What are the two gonads (primary reproductive organs)
a pair of testes and a pair of ovaries
What are the 2 dual functions in both male and female gonads
- To produce gametes through gametogenesis. This is spermatozoa in males and ova in eggs.
- Secrete sex hormones specifically testosterone in males and estrogen and progesterone in females
In females what is considered as accessory reproductive organs?
breasts
What is external genitalia?
The externally visible portion of the reproductive system
What are secondary sexual characteristics
The many external characteristics not directly involved in reproduction that distinguish males and females,
what two hormones in males and females govern the development and maintenance of secondary sexual characteristics?
testosterone in males and estrogen in females
What are the 2 essential male reproductive functions?
- Spermatogenesis
- Delivery of sperm to the female
What is the function of the scrotum (skin-covered sac)?
It suspends the testes outside the abdominal cavity and it lies between the legs
What are the 3 major accessory sex glands whose secretions provide the bulk of the semen ?
seminal vesicles, prostate gland and bulbourethral glands
What is the penis
The reproductive organ used to deposit semen into the vagina
What is the Glans penis
it is the sensitive erotic tissue at the tip of the penis that is important in sexual arousal
What makes up the male reproductive tract
Epidymis, vas deferens (ductus), ejaculatory duct.
The secretions of the male reproductive system empty into the?
Urethra
What is the urethra?
The canal that runs the length of the penis and empties to the exterior.
What are the 6 female reproductive functions for the complex female reproductive system?
- Oogenesis
- Reception of sperm
- fertilization/ conception
- gestation
- parturition
- Lactation
What is the product of fertilization in the intrauterine wall called in the first 2 months?
embryo
From 2 months to 9 months and above what is the developing fertilization product called
A fetus
Where is the female reproductive tract and ovaries located?
pelvic cavity
What makes up the female reproductive tract
2 oviducts (fallopian tubes), uterus, vagina, cervix, cervical canal, ovaries
What is ovulation?
The process of the ova being released from an ovary
What is the structure and function of the uterus?
it is a thick-walled hollow organ responsible for maintaining the fetus during development and expelling it at the end of gestation.
where is the site of fertilization?
the fallopian tubes
what is the vagina?
It is a muscular expandable tube and connects the uterus to the external environment.
The cervix projects into the__________
vagina
The vaginal opening is located in the ?
perineum(The external region that bounds the pelvic outlet)
The perineum is covered by a thin mucous membrane called the?
hymen
What surrounds the vaginal and urethral openings?
the labia minor and labia majora
What is the clitoris ?
it is erotic tissue that is mostly located internally except the externally visible part is called the glans clitoris.
The glans clitoris is made from similar tissue as the?
the glans penis
What is the female external genitalia collectively referred to as?
vulva
How many chromosomes does a somatic cell have
46 (Diploid)
Chromosomes composing a matching pair are called?
homologouus chromosomes
what is crossing over
refers to the physical
exchange of chromosome material between the homologous
pairs before their separation during the first meiotic division
sex determination is determined by?
The combination of sex chromosomes
Explain the difference in chromosome pair splitting in oogenesis and spermatogenesis
spermatogenesis: half of the sperm receive an X chromosome and the other half receives the Y chromosome
oogenesis: every ovum gets an X chromosome
When is genetic sex determined?
At the time of conception
How many chromosomes do gametes have
23 (Haploid)
What determines gender?
The male’s sperm (presence of it having the X or Y chromosome)
what are the three sex levels that males and females differ?
genetic sex, gonadal sex, phenotypic sex
what is gonadal sex
Whether testes or ovaries will develop due to the influence of genetic sex
when does gonadal specificity occur?
During the 7th week of pregnancy when the gonadal ridge of a genetic male begins to differentiate into testes under the influence of the sex-determining region of the Y chromosome (SRY)
What gene is solely responsible for sex determination
SRY
How does SRY masculinize the gonads?
by coding for the production of testis-determining factor (TDF) within primitive gonadal cells which then direct a series of events that leads to differentiation of the gonads into testes.
What is the other name for TDF?
SRY protein
Then how do females become females?
they lack SRY and consequently do not produce TDF, so by the 9th week of pregnancy the undifferentiated gonads start developing into ovaries guided by specific female gene products.
What is phenotypical sex?
the apparent anatomic sex of an individual which is hormonally mediated and influenced by gonadal sex.
Define sex differentiation
Embryonic development of the external genitalia and reproductive tract along either male or female lines
What masculanizing hormone secreted by developing testes induces differentiation into the male reproductive system?
androgens
What interval of weeks of gestation is when the gender of the baby is easily distinguished due to the external genitalia?
10-12 weeks
Male and female external genitalia develop from the same _______
embryonic tissue
the undifferentiated external genitalia consists of (3)………..
genital tubercle, paired urethral folds, genital (labioscrotal) swellings
The genital tubercle gives rise to?
the penis in males and clitoris in females
What do the urethral folds give rise to in males?
cord of erectile tissue
The fusion of genital swellings in males gives rise to?
the scrotum and prepuce
What is the scrotum
the sac that houses the testes.
What do the genital swellings and urethral folds develop into in females?
the labia minora and labia majora
what is the prepuce?
it is the skin that covers the penis and more or less completely covers the glans penis
what is cut during circumcision?
the prepuce
What are the two primitive duct systems that develop in all embryos?
the Wolffian ducts and the Müllerian ducts
Which primitive duct does the male reproductive duct develop from?
the Wolffian ducts and the Mullerian ducts degenerate
What primitive duct does the female reproductive tract develop from?
Mullerian ducts and the Wolffian ducts regress
Development of the reproductive tract in males and females depends on the presence of which 2 hormones in the fetal testes?
testosterone produced by Leydig cells and Mullerian-inhibiting factor produced by the early Sertoli cells.
