Log in
Biology
1
answer
0
watching
51
views

The menstrual cycle is repeated every 28 days and involves changes within the ovaries and uterus. What are the structural changes that occur during the ovarian cycle and uterine cycle?

Watch
1
answer
0
watching
51
views

For unlimited access to Homework Help, a Homework+ subscription is required.

Casey Durgan
Casey DurganLv2
28 Sep 2019

Unlock all answers

Get 1 free homework help answer.
Already have an account? Log in
Share

Related textbook solutions

Molecular Cell Biology
8 Edition,
Lodish
ISBN: 9781464183393
Biology: Science for Life with Physiology
6 Edition,
Belk
ISBN: 9780134555430
Biology
2nd Edition, 2013
Openstax
ISBN: 9781947172517
Concepts of Biology
OER Edition,
Openstax
ISBN: 9781938168116
Essentials of Biology
5 Edition,
Mader
ISBN: 9781259660269

Related questions

1. The site of implantation of a fertilized ovum is

A.The uterus
B.. The ovaries
C. The vag ina
D. The cervix

2. Which statement correctly describes the secretory phase of the uterine (menstrual) cycle?

A. Follicle stimulating hormone stimulates proliferation of the endometrium
B. During this phase, the endometrium detaches and sheds
C. Progesterone stimulates the endometrium to prepare for implantation
D. Decreased progesterone levels cause the endometrial cells to die

Which events in the monthly female reproductive cycle occur simultaneously?

A. Menstruation and the estrogen surge
B. Endometrial proliferation and development of the vesicular follicle
C. Degeneration of the corpus luteum and increased LH and FSH secretion
D. The secretory phase in the uterus and decreased progesterone levels

Please give some explanations, thanks.

Females of most mammalian species have estrus cycles instead ofmenstrual cycles. Such females usually come into estrus (alsocalled ‘in heat’) only once a year, generally in the spring. Thissingle estrus period is the only time mature, fertilizable eggs arepresent in the ovaries. Humans and a few other primate females,however, exhibit many menstrual cycles per year where fertilizableeggs are present in ovaries during each cycle. Discuss possibleadaptive advantages to each of these two strategies ofreproduction. Don’t forget an hypothesis.

Terms: 1, 14, 28, corpus luteum, estradiol, follicular,GnRH, inhibitory, LH surge, luteal, ovulatory, progesterone,regresses, stimulatory

The ovarian cycle refers to the recurrent, cyclic changes inhormone secretion and follicle/oocyte development that occurroughly every 28 days in the 'typical' woman. The ovarian cycle canbroadly be divided into 3 sequential phases, the first, or_____________ phase which precedes or comes before release of theegg, the middle or ____________ phase during which the egg isactually released, and the final or _______________ phase whichcomes after the egg is released and lasts until the next cyclebegins.

Day 1 of the follicular phase marks the beginning of a newcycle. During the follicular phase, as the name implies, a 'cohort'or small group of follicles (i.e. the structures in the ovary inwhich the oocytes are maturing) begin to grow, develop and preparetheir oocytes for release in response to FSH stimulation from theanterior pituitary. These follicles are the main hormone-secretingstructures in the ovary and the main hormone they are secreting is____________. Early in the phase, when estrogen levels are low, theestrogen exerts ____________feedback control on thehypothalamic-pituitary axis and keep GnRH, LH and FSH levelsrelatively low. Eventually, a single follicle assumes dominance,outgrows and out develops the others, and begins to secrete largerand larger amounts of estrogen. When estrogen levels becomesufficiently high, estrogen's effect at the hypothalamus becomestransiently ______________, causing increases in GnRH secretionthat trigger a mid-cycle _______________.

Right around mid-cycle or around day _________ of the 'typical'__________ day long cycle, under the influence of high levels of LHproduced by the LH surge, the wall of the dominant follicle thinsand eventually ruptures, releasing the egg. This release of the eggis termed ovulation, hence the portion of the cycle immediatelypreceding and including ovulation is termed the ovulatory phase.Another effect of LH is that it luteinizes the follicle, producingchanges in the follicle cells that enable the granulosa cells tosecrete ____________ in addition to estratiol.

The final phase of the ovarian cycle, the luteal phase, beginsimmediately after ovulation and lasts until day 1 of the nextcycle. The luteal phase is characterize by the presence andfunctioning of a _____________. This is the name for the structurethat develops from the follicle after it has lost its egg. Theremainder of the follicle involutes or falls in upon itself,becomes highly vascularized and its luteinized' cells secrete highconcentrations of progesterone in addition to estradiol. Theprogesterone exerts an overriding inhibitory effect on hypothalamic__________ secretion at this time. In the absence of pregnancy, theCL will remain highly active for ~12 days before it __________, orbegins to die off and cease its hormone-secreting activities. CLregression causes a rapid drop in the concentrations of estrogenand progesterone secretion over the next 2 days that will result inshedding of the endometrial lining of the uterus and menstruation.Day 1 of menstruation coincides with and serves as the externalindicator that day _________ of a new ovarian cycle has begun.

Weekly leaderboard

Home
Homework Help 3,900,000
Biology 460,000
Start filling in the gaps now
Log in