(a) In girls, the first menstrual cycle occurs at the onset of puberty.Outline the role of progesterone in the human menstrual cycle. 相关知识点: 试题来源: 解析 (a)1. (mostly) secreted, during the second half of the cycle / from day 14 onwards ;2.maintains, lining of the uterus / ...
The menstrual phase is the first phase of the menstrual cycle during which the lining of the uterus, called theendometrium, is shed as menstrual flow out of thecervix and vagina. Females experience this process during their menstrual periods, and the menstrual flow itself consists of a mixture ...
The menstrual cycle is about four weeks long, starting on the first day of bleeding and ending when the next period begins. However, it can vary greatly when girls first starts their period. It may skip months or come several times per month for up to 2 years. It may be cramp-free ea...
menstrual phase- the phase of the menstrual cycle during which the lining of the uterus is shed (the first day of menstrual flow is considered day 1 of the menstrual cycle) luteal phase,secretory phase- the second half of the menstrual cycle after ovulation; the corpus luteum secretes progeste...
A menstrual cycle starts on the first day of the period and ends at the start of the next period. An entire menstrual cycle usually lasts between 24 and 38 days (2), but menstrual cycles can vary from person to person, cycle to cycle[4], and may also change over the years. ...
The human female menstrual cycle is marked by the regular occurrence of menses appearing on average once every 28 days starting at puberty and ending at menopause. It is controlled by the endocrine system and requires adequate hormonal and nutritional status to function. Since the menstrual cycle ...
This article defines the menstrual cycle phases and hormones: menstruation, follicular phase, proliferative phase, ovulation, luteal phase, secretory phase.
First week: Theuteruslining, which thickened in the previous period, breaks down and is lost as blood-flow through thevagina. 第一周:在上一个周期中变厚的子宫内膜开始分解,并随着经血通过阴道排出体外。 Second week: an egg-containingfolliclenear theovary'ssurfaceswellsas itripens. Theuteruslining ...
of the lining of the uterus.Name the hormone that stimulates:(i) the growth of the lining of the uterus during the first half of the menstrual cycle(ojestrogen...[1](ii) the maintenance of the lining of the uterus during the second half of the menstrual cycle progesterone.[1](c)Fig....
The period of vaginal bleeding known as the menstrual period is generally considered the final step in the menstrual cycle. Once the menstrual period has ended, the menstruation cycle typically begins anew.levels in the fertile woman's body typically rise during the first two weeks of the cycle...