Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physiology II > reproduction > Flashcards

reproduction Flashcards

1
Q

functions of gonads (ovaries or testes)

A

produce gametes (spermatozoa or ova)

produce steriod “sex” hormones (mostly testosterone in males; mostly estradiol and progesterone in females)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

testosterone belongs to a group of similar hormones having similar masculinizing actions called ____

A

androgens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

in males, most of the testosterone is made by the ____ ; other less potent androgens are made by the ____ ____

A

testes

adrenal cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

estradiol belongs to a group of similar hormones called ____ that are secreted in large amounts by the ____ and ____

A

estrogens

ovaries and placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

estrone is an estrogen produced:

estriol is produced:

estrogens are produced:

A

by the ovaries and placenta

by the placenta, and is usually found only in pregnant women

from androgens by the enzyme aromatase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

males produce ____ amounts of estrogens

females produce small amounts of ____ , most of which come from the ____ ____

A

small

androgens

adrenal cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

progesterone is produced by the ____ and ____

it is an intermediate in the synthetic pathways for:

A

ovaries and placenta

adrenal steroids, estrogens, and androgens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

all steroid hormones act via

A

intracellular receptors to alter the rate of formation of particular mRNAs and thus intracellular proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

accessory reproductive organs

A

the system of ducts through which sperm or ova are transported and the glands lining or emptying into them (also included here are breats in females)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

secondary sexual characteristics

A

the external differences between males and females (characteristic body shape, hair distribution, average adult height, etc.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

chain of hormones that largely controls reproductive function:

  • ____ is released from the hypothalamus into the portal blood vessel leading to the anterior pituitary, where it stimulatess the relase of ……
  • ____ ( ____ ____ and ____ ____ ) these travel in the blood to the gonads, resulting in ….
  • the maturation of ____ or ____ and the stimulation of sex hormone secretion which exert many effects on all parts of the reproductive system (including the gonad from which they came) and on other body parts too
  • the gonadal steriods exert feedback effects on the secretion of ____ , ____ , and ____
  • gonadal protein hormones such as ____ also exert feedback effects on the anterior pituitary
A
  • gonadotropin-releasing hormone (GnRH)
  • gonadotropins (luteinizing hormone and follicle-stimulating hormone)
  • sperm or ova
  • GnRH, LH, and FSH
  • inhibin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

germ cells

A

cells that will develop or are developing into gametes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

first stage of gametogenesis:

  • primordial, undifferentiated germ cells (called ____ in males and ____ in females) first proliferate by ____ in which each of the two daughter cells resulting from the cell division receives a full set of ____ chromosomes identical to those of the original dividing cell
  • this provides a supply of identical germ cells for the next stage (that is, it provides more spermatogonia or oogonia, some of which will eventually be called ____ spermatocytes or oocytes)
  • in females, this mitosis occurs during ____ development; in males, it starts after ____ and continues throughout the rest of life
A
  • spermatogia oogonia mitosis 46
  • primary
  • fetal
  • puberty
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

second stage of gametogenesis:

  • primary spermatocyte or oocyte divides by ____ which involves
  • two successive divisions (with meiosis I producing two secondary ____ or one secondary ____ and one polar body, and meiosis II producing two ____ from each secondary spermatocyte or one ____ and another polar body from the secondary oocyte
A
  • meiosis
  • spermatocytes oocyte spermatids ovum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

in meiosis I, the ____ chromosomes are dealt to the two cells being produced, so that each secondary spermatocyte or secondary oocyte contains ____ chromosomes

A

46

23

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

in meiosis II, a cell with ____ chromosomes gives rise to two spermatids with ____ each or an ovum with ____ and a polar body with ____

A

23

23

23

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

after meiosis II, the resulting sperm and ova are not genetically ____ to one another nor to the ____ germ cell that gave rise to them; thus the siblings from the same parents are far from being genetically identical

A

identical

primordial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

seminiferous tubules

the walls of each tubule are formed from

A

sites of spermatogenesis in the testes

develop germ cells and sertoli cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

leydig (interstitial) cells

A

are in the connective-tissue spaces between the tubules

synthesize and release testosterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

the mitoitc cell division by spermatogonia in the walls of seminiferous tubules to produce primary spermatocytes begins

A

at puberty and continues throughout the rest of life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

each stem cell spermatogonium undergoes a specified number of mitotic divisions to produce a clone of ____ ; a little differentiation occurs along the way, and cells resulting from the final mitotic division are called:

A

spermatogonia

primary spermatocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

if all the cells in the clone produced by each stem cell spermatogonium followed the differentiation pathway, the spermatogonia would disappear, as all of them would be converted to:

this is prevented by, at an early point, one of the cells of each clone “dropping out” of the mitosis-differentiation cycle to:

A

primary spermatocytes

remain a stem cell spermatogonium (which will enter its own full sequence of divisions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

in spermatogenesis, meiosis I and II produce

A

4 enlarged spermatids from one primary spermatocyte

24
Q
  • in the final step of spermatogensis, spermatids differentation into ____ (sperm) ; this involves cell remodeling, including ____ :
    • the sperm cell head is almost all ____ and contains the DNA; the tip of the nucleus is covered by the ____ , and protein- filled vesicle containing enzymes needed in fertilization
    • most of the tail is a ____ (contractile filaments that produce movements capable of propelling the sperm)
    • the body (midpiece) of the sperm contains ____ that provide the energy for movement
A
  • spermatozoa elongation
    • nucleus acrosome
  • flagellum
  • mitochondria
25
Q

participation of sertoli cells:

  • each sertoli cell extends from the base of the ____ ____ (where there is a basement membrane) all the way to the tubule’s ____
  • sertoli cells send out extensions that join the extensions of other sertoli cells; ____ ____ are between the extensions of adjacent cells
  • the ring of sertoli cells interconnected by tight junctions forms a ____ ____ ____ , which prevents the movement of many chemicals from the blood into the tubule lumen and thereby ensures proper conditions for germ cell development and differentation
  • mitosis of spermatogonia occurs at the ____ of the seminiferous tubule; the primary spermatocytes then migrate through the tight junctions to eventually gain entry into the tubule’s ____
  • when sperm formation is complete, the sertoli cells cytoplasm around the sperm ____, and the sperm are released in the ____
A
  • seminiferous tubule lumen
  • tight junctions
  • blood testis barrier
  • base lumen
  • retracts lumen
26
Q

other functions are sertoli cells:

  • serve as the route by which _____ reach developing germ cells
  • secrete most of the ____ found in the tubule lumen
  • in response to ____ and to local ____ produced by leydig cells, secrete a variety of chemical messengers that function as paracrines to stimulate differentiation of the germ cells
  • secrete the hormone ____
  • secrete paracrines that affect ____ cell function
  • ____ defective sperm
  • secrete, during embryonic life, a substance that causes the primordial ____ duct system to regress
A
  • nutrients
  • fluid
  • FSH testosterone
  • inhibin
  • leydig
  • phagocytize
  • female
27
Q

from the seminiferous tubules, sperm travel through the ____ ____ , a network of interconnected tubes formed by the convergence of seminiferous tubules from different testicular areas

A

rete testis

28
Q

after leaving the rete testis, sperm move into ____ ____ , which empty into the ____ , which is loosely attached to the testicular surface

A

efferent ductules

epididymis

29
Q

the epididymis leads to the ____ ____ , a thick-walled tube lined with smooth muscle, which is bound together with blood vessels and nerves to form the ____ ____

A

vas deferens

spermatic cord

30
Q

inguinal canal

A

slit-like opening that allows the spermatic cord to pass between the scrotum and abdominopelvic cavity

31
Q

on each side of the body, the duct from a large, glandular ____ ____ joins the vas deferens to form an ____ ____ , which travels through the ____ ____ to join the ____ (which is coming from the urinary bladder and enters the penis after emerging from the prostrate

A

seminal vesicle

ejaculatory duct

prostate gland

urethra

32
Q

in addition to fluid and sperm from the vas deferens, semen contains large amounts of fluid from the two ____ ____ and the ____ ____ , and small amounts from mucous glands, especially the two ____ ____

A

seminal vesicles

prostate gland

bulbourethral glands (cowper’s glands)

33
Q

in addition to sperm, semen contains

A

nutrients

buffers for protecting sperm against the acidic vaginal secretions

chemicals that increase sperm motility

fibrinogen

prostaglandins

34
Q

sperm are nonmotile early in the pathway, and movement as far as the ____ results from:

A

epididymis

the pressure created by fluid secretion from the Sertoli cells

35
Q

fluid absorption as fluid travels through the epididymis

A

concentrates the sperm

36
Q

peristaltic contractions of ____ and ____ ____ smooth muscle tissue propel the semen forward

A

epididymis

vas deferens

37
Q

penis consists mostly of

A

three cylindrical, vascular compartments that run its entire length

38
Q

during sexual excitement, erection occurs as neural input to the arteries supplying the vascular compartments causes

A

the arteries to dilate, and the compartments become engorged with blood under high pressure

39
Q

in male sexual excitement, the engorgement of blood passivley compresses

A

the veins draining the compartments, further increasing the local pressure

40
Q

before erection, the main neural input to the arteries is ____ released from ____ neurons

A

norepinephrine

sympathetic

41
Q

during erection, the sympathetic input is inhibited, and ____ neurons to the arteries that release the unusual transmitter ____ ____ become active; nitric oxide relases the arterial ____ ____

A

parasympathetic

nitric oxide

smooth muscle

42
Q

the main receptors that initiate the erection reflex are ____ in the genital region, especially in the head of the penis

A

mechanoreceptors

43
Q

during erection, sensory neurons carry impulses from the mechanoreceptors to the inferior parts of the spinal cord; interneurons here control

A

the outflow of neural signals to the penile arteries

44
Q

ejaculation is a reflex initiated by sensory pathways from

A

penile mechanoreceptors traveling to teh spinal cord centers

45
Q

ejaculaiton:

  • a patterned sequence of impulses in ____ neurons leading from the spinal cord results in
    • ____ , ____ ____ , ____ ____ , ____ , and ____ ____ smooth muscle contraction as a result of stimulation by ____ neurons; this empties semen into the urethra ( ____ )
    • semen’s being expelled from the urethra by a series of rapid contractions of ____ smooth muscle and skeletal muscle as the base of the ____ ( the latter is controlled by somatic motor neurons)
A
  • efferent
    • epididymis, vas deferens, ejaculatory duct, prostate, and seminal vesicle sympathetic emission
    • urethral penis
46
Q

the GnRH-secreting neuroendocrine cells of the ____ fire a burst of action potentials about every 90 minutes to secrete pulses of GnRH

A

hypothalamus

47
Q

GnRH reaches the ____ ____ via the portal blood vessels connecting the two structures, and triggers the release of both ____ and ____ from the same cell type; thus these hormones are released in pulses

A

anterior pituitary

LH and FSH

48
Q

FSH acts mainly on the ____ cells to stimulate the secretion of paracrines required for ____

A

sertoli

spermatogenesis

49
Q

LH acts mainly on the ____ cells to trigger ____ secretion

A

leydig

testosterone

50
Q

testosterone secreted by leydig cells enters the blood to act hormonally/systemically, but it also acts locally, in a paracrine manner, by diffusing from the ____ ____ into the ____ ____ ;

it enters ____ cells, where it facilitates ____

A

interstitial spaces

seminiferous tubules

sertoli

spermatogenesis

51
Q

negative hormonal feedback effects:

  • testosterone inhibits ____ secretion by
    • acting on the ____ to decrease ____ secretion
    • and acting directly on the ____ ____ to decrease the ____ response to GnRH
  • ____ released by sertoli cells, acts directly on the anterior pituitary to decrease ____ secretion
A
  • LH
    • hypothalamus GnRH
    • anterior pituitary LH
  • inhibin FSH
52
Q

other effects of testosterone

A
  • induces differentiation of male accessory reproductive organs and maintains their functions
  • induces male secondary sex characteristics; opposes action of estrogen on breast growth
  • stimulates protein anabolism, bone growth, and cessation of bone growth
  • required for sex drive and may enhance aggressive behavior
  • stimulates erythropoietin secretion by kidneys
53
Q

some hormones must undergo changes within target cells to be effective; this is true for testosterone in many of its target cells:

in adult prostate cells, testosterone is converted to ____ catalyzed by the enzyme 5 alpha-reductase)

in certain other targets cells (for example in the brain), testosterone is converted to ____ (catalyzed by aromatase)

A

dihydrotestosterone

estradiol

54
Q

some males lack 5 alpha-reductase or aromatase in some tissues, in such a case, they will exhibit

A

certain signs of testosterone deficiency but not others

55
Q

the fetal differentiation and later growth and function of the entire male duct system, glands, and penis all depend on testosterone, following the loss of testicular function, what occurs

A

accessory organs decrease in size, the glands markedly reduce their secretion rates, the smooth muscle activity of the ducts is diminished, and sex drive - erection - and ejaculation are usally impaired

56
Q

during childhood, the hypothalamus does not secrete significant amounts of ____ , for reasons not yet understood, at the time of ____ , GnRH secretion begins

A

GnRH

puberty

57
Q

most if not all of the observable changes that occur at puberty depend on ____ or its metabolite ____

A

testosterone

DHT

Physiology II (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions