C3: Gametogenesis and Hormones in Reproduction and Development

Question 1

four phases of gametogenesis:

Answer 1

a.) the extraembryonic origin of the germ cells and their migration into the gonads,
b.) an increase in the number of germ cells by mitosis,
c.) a reduction in chromosomal number by meiosis, and
d.) structural and functional maturation of the eggs and spermatozoa

Question 2

the process of sperm cell production
▪ prolific and continuous process in the adult male
▪ occurs in the paired male gonads, or testes, specifically in the seminiferous tubules

Answer 2

Spermatogenesis

Question 3

Primordial germ cells of the embryonic testes differentiate into ___, the diploid cells that are the precursors of sperm.

Answer 3

spermatogonia

Question 4

are undifferentiated cells located near the outer wall of the seminiferous tubules.

Answer 4

Spermatogonia

Question 5

In a mature male, about 3 million spermatogonia per day differentiate into ___

Answer 5

primary spermatocytes

Question 6

Each primary spermatocyte undergoes first meiotic division producing ___

Answer 6

haploid secondary spermatocytes.

Question 7

In the second meiotic division, each secondary spermatocyte gives rise to ___

Answer 7

two haploid spermatids.

Question 8

what are produced from the original primary spermatocyte?

Answer 8

Four spermatids

Question 9

Spermatids then differentiate into ______ The differentiation of the spermatids into sperm cells is called ___.

Answer 9

into a mature sperm cell or spermatozoa.;
spermiogenesis

Question 10

Spermatogenesis involves association of the developing sperm with large ____, which transfer nutrients to the spermatozoa.

Answer 10

Sertoli cells

Question 11

The release of a sperm cell from its connection to a Sertoli cell is known as ___.

Answer 11

spermiation

Question 12

During spermatogenesis, the developing sperm are gradually pushed toward the _____, flow toward ___ and make their way to the ___ where they acquire motility.

Answer 12

center or lumen of seminiferous tubules;
ducts of the testes;
epididymis

Question 13

Each mature sperm consists of a ___, ___, and ___.

Answer 13

head, midpiece, and flagellum (tail)

Question 14

The head of sperm consists of the ___ and the nuclear material DNA and a cap called ___ that produces enzymes ___ and ___ that aid sperm cell to penetrate the secondary oocyte.

Answer 14

nucleus;
acrosome; hyaluronidase and proteinases

Question 15

Numerous mitochondria, located in the ___ of the sperm (provides the energy (ATP) for locomotion).

Answer 15

midpiece

Question 16

flagellum has a typical eukaryotic arrangement of _____propels the sperm along its way.

Answer 16

9+2 microtubules

Question 17

differentiation of the spermatids into sperm cells; corresponds to the final part of spermatogenesis

Answer 17

Spermiogenesis

Question 18

Stages of Spermiogenesis (6)

Answer 18

1.) Formation of the Acrosomal Cap
2.) Condensation of the Nucleus
3.) Development of the Flagellum
4.) Sheath Arrangement of the Mitochondria
5.) Cytoplasm Reduction
6.) mature sperm enveloped by plasma membrane

Question 19

The development of the acrosomal cap is due to the coalescence of the vesicles of the Golgi apparatus which pinch off from it and forms a membranous structure called ____.

Answer 19

acrosome

Question 20

contains enzymes that play important role in the penetration through the zona pellucida of the oocyte.

Answer 20

Acrosome

Question 21

This organelle supports the developing flagellum which extends into the lumen of the tubule.

Answer 21

centriole

Question 22

▪ development of ova (mature, unfertilized egg) from oogonia
▪ involves meiosis and occurs in the ovaries (the female gonad)

Answer 22

Oogenesis

Question 23

___arises from the primordial germ cell dividing by meiosis in the ovary into ___

Answer 23

Oogonium; oocyte

Question 24

During prenatal development, the oogonia increase in size and become ___.

Answer 24

primary oocyte

Question 25

By the time of birth, primary oocyte are in the __ of the ___. At this stage, they enter a resting phase that last throughout childhood and into the adult life.

Answer 25

prophase of the first meiotic division

Question 26

primary oocyte and the cluster of cells surrounding it together make up a __

Answer 26

follicle.

Question 27

With the onset of puberty a few follicles develop each month in response to __ secreted by the anterior pituitary gland.

Answer 27

FSH

Question 28

The two cells produce are different in size. The smaller one, the ___, may later divide forming two polar bodies bit eventually disintegrate. The larger cell, the ____, proceeds to the second meiotic division but remains in ___ until it is fertilized.

Answer 28

first polar body; secondary oocyte; metaphase

Question 29

When meiosis does not continue, the second meiotic division gives rise to a ___ and a ___

Answer 29

single ovum; second polar body.

Question 30

Each primary spermatocyte gives rise to ___ . In contrast, each primary oocyte generates ___

Answer 30

four sperm; only one ovum.

Question 31

As follicle develops, it becomes separated from its surrounding follicle cells by a thick membrane, the ___

Answer 31

zona pellucida.

Question 32

At ovulation, the ___ is ejected through the wall of the ovary and into the ___

Answer 32

secondary oocyte; pelvic cavity.

Question 33

The portion of the follicle that remains in the ovary develops into the ___ (temporary endocrine gland) wherein it secretes ____

Answer 33

corpus luteum; estrogens and progesterone.

Question 34

Once the secondary oocyte exits the ovary, it begins to travel down the ___

Answer 34

uterine (fallopian tube).

Question 35

The second meiotic division only occurs when ___ happens

Answer 35

fertilization

Question 36

▪ in the process known as ___, the follicle ruptures releasing a secondary oocyte

Answer 36

ovulation

Question 37

Production of ova begins with mitosis of the primordial germ cells in the embryo, producing ____. Each oogonium develops into ___, which is also diploid.

Answer 37

diploid oogonia (2n); primary oocyte

Question 38

cyclic, physiologic changes in the levels of hormones that cause the release of an egg from the ovary and thickening of the lining of the uterus (endometrium) in preparation of receiving and nourishing a fertilized egg

Answer 38

Menstrual Cycle

Question 39

this cycle recurs approximately every four week from puberty through menopause ▪ occurs in female of reproductive age

Answer 39

Menstrual Cycle

Question 40

Two kinds of menstruation:

Answer 40

Overt menstruation Covert menstruation

Question 41

where there is blood flow from the vagina occurs primarily in humans and close evolutionary relatives such as chimpanzees;

Answer 41

Overt menstruation

Question 42

where there is no blood flow, the endometrium is completely resorbed by the animal at the end of its reproductive cycle; occurs in females of other species of placental mammals that have estrous cycle

Answer 42

Covert menstruation

Question 43

Menstrual cycle can be divided into several phases: 3

Answer 43

o Menstruation o Follicular phase o Luteal phase

Question 44

defines the transition from the follicular phase to the luteal phase.

Answer 44

Ovulation

Question 45

Stimulated by gradually increasing amounts of __ in the ___ phase, the lining of the uterus thickens

Answer 45

estrogens; follicular

Question 46

The dominant follicle releases an ___ in an event called __.

Answer 46

ovum, or egg; ovulation

Question 47

After ovulation, the remains of the dominant follicle in the ovary become the ____; this so called yellow body has a primary function of producing large amounts of ___.

Answer 47

corpus luteum; progesterone

Question 48

Under the influence of ___, the endometrium (uterine lining) changes and thickens in preparation for possible ___ of an embryo to establish ___.

Answer 48

progesterone; implantation; pregnancy

Question 49

If implantation does not occur within approximately two weeks, the corpus luteum will disintegrate and die, causing sharp drops in levels of both ____

Answer 49

progesterone and estrogens

Question 50

Drop in the level of hormone concentration, causes the uterus to shed its lining in a process termed as ___.

Answer 50

menstruation

Question 51

The ____ also comprises the recurring physiologic changes that are induced by reproductive hormones in most mammalian placental females

Answer 51

estrous cycle

Question 52

Estrous cycles start after puberty in sexually mature females and are interrupted by ___

Answer 52

anestrous phases

Question 53

Mammals share the same reproductive system: -regulatory hypothalamic system= releases ____ in pulses, -pituitary= secretes ___ and ___ -ovary = releases ___ and ___

Answer 53

gonadotropin releasing hormone; follicle stimulating hormone and luteinizing hormone; sex hormones; estrogens and progesterone.

Question 54

A woman’s first menstruation is termed ___, and is one of the later stages of puberty in girls

Answer 54

menarche

Question 55

The cessation of menstrual cycles at the end of the woman’s reproductive life is termed ___.

Answer 55

menopause

Question 56

menstrual cycle can be divided into the following parts: 2

Answer 56

1.) ovarian cycle; and 2.) uterine cycle

Question 57

OVARIAN CYCLE is further divided in 3 phases:

Answer 57

Follicular phase Ovulation Luteal phase

Question 58

time from the first day of menstruation until ovulation when a mature egg is released from the ovary

Answer 58

Follicular phase

Question 59

growth and maturation of the egg is taking place inside the follicle, a small sac where the egg matures.

Answer 59

Follicular phase

Question 60

occurs around day 14 of the cycle, in response to a surge of luteinizing hormone (LH) that occurs just before the egg is released from the ovary.

Answer 60

Ovulation

Question 61

is the time from when the egg is released (ovulation) until the first day of menstruation

Answer 61

Luteal phase

Question 62

2 phases of uterine cycle:

Answer 62

Proliferative phase Secretory phase

Question 63

This uterine cycle phase is the time after menstruation and up to ovulation.

Answer 63

Proliferative phase

Question 64

When menstruation is over, the endometrium grows and thickens during this period to prepare for implantation of an embryo (fertilized egg). What uterine phase?

Answer 64

Proliferative phase

Question 65

This uterine cycle phase is the time after ovulation and before the start of a woman’s period. Glands within the endometrium secrete proteins in preparation for a fertilized egg to implant.

Answer 65

Secretory phase

Question 66

During each cycle, the brain’s ___ and __ send hormone signals back and forth with the __.

Answer 66

hypothalamus and pituitary gland; ovaries

Question 67

The hormones __ and ___ play the biggest roles in how the uterus changes during each cycle.

Answer 67

estrogens and progesterone

Question 68

this hormone build up the lining of the uterus; whereas this hormone increase after an ovary releases an egg at ovulation in the middle of the cycle.

Answer 68

Estrogens; Progesterone

Question 69

chemical substances formed in tissues organs carried by the blood; stimulates or inhibits the growth or function

Answer 69

Hormones

Question 70

Hormones in Reproduction and Development (5)

Answer 70

1. Gonadotropin-releasing hormone (GnRH) 2. Follicle-stimulating hormone 3. Luteinizing hormone 4. Estrogens 5. Progesterone

Question 71

produced by the hypothalamus; stimulates the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary gland

Answer 71

1. Gonadotropin-releasing hormone (GnRH)

Question 72

▪ produced by the anterior pituitary gland ▪ stimulates the growth of follicles in the ovaries which secrete estrogens

Answer 72

2. Follicle-stimulating hormone

Question 73

▪ also produced by the anterior pituitary gland ▪ works with the FSH to cause ovulation and later the release of estrogens and progesterone.

Answer 73

3. Luteinizing hormone

Question 74

hormones secreted by the ovarian follicles and corpus luteum ▪ stimulates thickening of the uterine wall, maturation of an egg, and development of the female sex characteristics ▪ also provides feedbacks to inhibit FSH secretion and increase LH secretion.

Answer 74

4. Estrogens

Question 75

▪ hormones secreted by the corpus luteum ▪ stimulates thickening of the uterine wall and formation of mammary ducts

Answer 75

5. Progesterone

Question 76

▪ __ stimulates enlargement of a few primary ovarian follicles and the subsequent maturation of the dominant follicle.

Answer 76

FSH

Question 77

▪ FSH with the involvement of LH promotes estrogen secretion by ___

Answer 77

follicular cells.

Question 78

___ stimulates the thickening of the uterine lining and exerts a negative feedback inhibition on ___ by the hypothalamus.

Answer 78

estrogen; GnRH secretion

Question 79

A rapid rise in __ concentration peaks on day __ as the dominant follicle enlarges.

Answer 79

estrogen; 12

Question 80

__ transforms the ruptured follicle into a corpus luteum and stimulates the corpus luteum to secrete increasing amounts of __ and __ during days ___

Answer 80

LH; progesterone and estrogen; 17 to 23.

Question 81

Progesterone exerts a negative feedback on GnRH secretion by the hypothalamus, inhibiting the release of ___ from the __

Answer 81

FSH and LH; anterior pituitary.

Question 82

Female Disorders (9)

Answer 82

a.) Amenorrhea b.) Dysmenorrhea c.) Endometriosis d.) Adenomyosis e.) Pelvic inflammatory disease (PID) f.) Use of an intrauterine device (IUD) g.) Uterine fibroids and uterine polyps h.) Infertility i.) Cancer

Question 83

hormone-like substances involved in pain and inflammation, trigger uterine muscle contractions.

Answer 83

Prostaglandins,

Question 84

absence of menstruation

Answer 84

a.) Amenorrhea

Question 85

___ is the failure of a woman to begin menstruation, and is caused by endocrine disorders or abnormal reproductive development

Answer 85

Primary amenorrhea

Question 86

___ is the absence of one or more menstrual periods without pregnancy.

Answer 86

Secondary amenorrhea

Question 87

painful menstruation that prevents a woman from doing her normal activity for one or more days during her menses

Answer 87

b.) Dysmenorrhea

Question 88

Experts believe that ___ are the direct cause of dysmenorrhea. Increased ___ – substances involved in inflammation also may be a contributing factor.

Answer 88

prostaglandins; leukotriene levels

Question 89

a painful condition, the type of tissue that lines the uterus becomes implanted outside the uterus, most commonly in the fallopian tube, ovaries, or the tissue lining the pelvis.

Answer 89

c.) Endometriosis

Question 90

a condition that occurs when the tissue that lines the uterus begin to grow within the muscular walls of the uterus.

Answer 90

d.) Adenomyosis

Question 91

infection of the female reproductive organs caused by sexually transmitted bacteria.

Answer 91

e.) Pelvic inflammatory disease (PID)

Question 92

a small, plastic, T-shaped birth control device inserted into the uterus may cause increased cramping, particularly during the first few months after insertion.

Answer 92

f.) Use of an intrauterine device (IUD)

Question 93

are non-cancerous tumors and growth that protrude from the lining of the uterus.

Answer 93

g.) Uterine fibroids and uterine polyps

Question 94

inability to conceive. It may be caused by tubal obstruction, ovarian disease, or lack of maintenance of the uterine lining.

Answer 94

h.) Infertility

Question 95

is a slow-growing cancer caused by ____ infections of sexual partners and associated with multiple sex partners. It can usually be detected early by a Pap smear. Annual

Answer 95

Cervical cancer; human papillomavirus