File Name: cervix anatomy and physiology .zip
Uterus , also called womb , an inverted pear-shaped muscular organ of the female reproductive system , located between the bladder and the rectum. It functions to nourish and house a fertilized egg until the fetus , or offspring, is ready to be delivered. The uterus has four major regions: the fundus is the broad curved upper area in which the fallopian tubes connect to the uterus; the body, the main part of the uterus, starts directly below the level of the fallopian tubes and continues downward until the uterine walls and cavity begin to narrow; the isthmus is the lower, narrow neck region; and the lowest section, the cervix , extends downward from the isthmus until it opens into the vagina. The uterus is 6 to 8 cm 2.
Uterus , also called womb , an inverted pear-shaped muscular organ of the female reproductive system , located between the bladder and the rectum. It functions to nourish and house a fertilized egg until the fetus , or offspring, is ready to be delivered. The uterus has four major regions: the fundus is the broad curved upper area in which the fallopian tubes connect to the uterus; the body, the main part of the uterus, starts directly below the level of the fallopian tubes and continues downward until the uterine walls and cavity begin to narrow; the isthmus is the lower, narrow neck region; and the lowest section, the cervix , extends downward from the isthmus until it opens into the vagina.
The uterus is 6 to 8 cm 2. The width of the organ varies; it is generally about 6 cm wide at the fundus and only half this distance at the isthmus. The uterine cavity opens into the vaginal cavity, and the two make up what is commonly known as the birth canal. Lining the uterine cavity is a moist mucous membrane known as the endometrium.
The lining changes in thickness during the menstrual cycle , being thickest during the period of egg release from the ovaries see ovulation. If the egg is fertilized , it attaches to the thick endometrial wall of the uterus and begins developing. If the egg is unfertilized, the endometrial wall sheds its outer layer of cells ; the egg and excess tissue are then passed from the body during menstrual bleeding.
The endometrium also produces secretions that help keep both the egg and the sperm cells alive. The components of the endometrial fluid include water , iron , potassium , sodium , chloride, glucose a sugar , and proteins.
Glucose is a nutrient to the reproductive cells, while proteins aid with implantation of the fertilized egg. The other constituents provide a suitable environment for the egg and sperm cells. The uterine wall is made up of three layers of muscle tissue.
The muscle fibres run longitudinally, circularly, and obliquely, entwined between connective tissue of blood vessels , elastic fibres, and collagen fibres.
This strong muscle wall expands and becomes thinner as a child develops inside the uterus. After birth, the expanded uterus returns to its normal size in about six to eight weeks; its dimensions, however, are about 1 cm 0. The uterus is also slightly heavier and the uterine cavity remains larger. The uterus of a female child is small until puberty , when it rapidly grows to its adult size and shape. After menopause , when the female is no longer capable of having children, the uterus becomes smaller, more fibrous, and paler.
Some afflictions that may affect the uterus include infections; benign and malignant tumours ; malformations, such as a double uterus; and prolapse, in which part of the uterus becomes displaced and protrudes from the vaginal opening. Uterus transplantation , in which a uterus from a healthy female is transplanted into the affected woman, has been considered a potential form of treatment in extreme cases of uterine disease or absence of the uterus; the first birth of a healthy infant to a uterus transplant recipient occurred in Uterus Article Media Additional Info.
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External Websites. The Editors of Encyclopaedia Britannica Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree See Article History. The uterus is an inverted pear-shaped muscular organ of the female reproductive system, located between the bladder and the rectum.
It functions to nourish and house the fertilized egg until the unborn child is ready to be delivered. Read More on This Topic. The uterus, or womb, is shaped like an inverted pear. It is a hollow, muscular organ with thick walls, and it has a glandular lining called Get a Britannica Premium subscription and gain access to exclusive content. Subscribe Now. Learn More in these related Britannica articles:. It is a hollow, muscular organ with thick walls, and it has a glandular lining called the endometrium.
In an adult the uterus is 7. The uterus is a thick-walled, pear-shaped organ measuring seven centimetres about 2. It has a buttonlike lower end, the cervix,…. As the uterus enlarges, it elevates the diaphragm. This in turn pushes the heart upward, to the left, and somewhat forward, so that it is nearer the chest wall beneath the breast.
Near the end of gestation the large uterus may raise the heart until the latter…. History at your fingertips. Sign up here to see what happened On This Day , every day in your inbox! Email address. By signing up, you agree to our Privacy Notice. Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox.
If you create an account, you can set up a personal learning profile on the site. Now that you have completed this study session, you can assess how well you have achieved its Learning Outcomes by answering these questions. You can check your answers with the Notes on the Self-Assessment Questions at the end of this Module. Choose the correct directional terms from Box 3. The uterus is anterior to in front of and superior to above the rectum.
The cervix or cervix uteri Latin, 'neck of the uterus' is the lower part of the uterus in the human female reproductive system. The narrow, central cervical canal runs along its entire length, connecting the uterine cavity and the lumen of the vagina. The opening into the uterus is called the internal os , and the opening into the vagina is called the external os. The lower part of the cervix, known as the vaginal portion of the cervix or ectocervix , bulges into the top of the vagina. The cervix has been documented anatomically since at least the time of Hippocrates , over 2, years ago. The cervical canal is a passage through which sperm must travel to fertilize an egg cell after sexual intercourse.
The uterus is a secondary sex organ. Secondary sex organs are components of the reproductive tract that mature during puberty under the influence of sex hormones produced from primary sex organs the ovaries in females and the testes in males. The uterus is a thick-walled muscular organ capable of expansion to accommodate a growing fetus.
These parts are internal; the vagina meets the external organs at the vulva, which includes the labia, clitoris, and urethra. The vagina is attached to the uterus through the cervix, while the uterus is attached to the ovaries via the fallopian tubes. At certain intervals, the ovaries release an ovum, which passes through the fallopian tube into the uterus.
the gross and microscopic anatomy of the uterine cervix and the physiology of the transformation zone. The cervix is the lower fibromuscular portion of the uterus.
The cervix is the lower portion of the uterus , an organ of the female reproductive tract. Anatomically and histologically, the cervix is distinct from the uterus, and hence we consider it as a separate anatomical structure. In this article, we shall look at the structure of the cervix, its vasculature, innervation, functions, and any clinical relevance. It is lined by stratified squamous non-keratinized epithelium. The opening in the ectocervix, the external os, marks the transition from the ectocervix to the endocervical canal. It is lined by a mucus-secreting simple columnar epithelium. Fig 1.
Colposcopy of Female Genital Tract pp Cite as. It becomes necessary for a gynecologist to be well aware of the anatomy and physiology of cervix as this knowledge forms the basis for an effective program of cervical cancer screening. In this chapter, we attempt to recapitulate both gross and microscopic anatomy of the uterine cervix and the physiology of the transformation zone. Skip to main content.
- Женщина улыбнулась и протянула ему тонкую изящную руку. - Дэвид Беккер. - Он пожал ее руку. - Примите мои поздравления, мистер Беккер. Мне сказали, что вы сегодня отличились.
О! - Старик радостно улыбнулся.
Ты представляешь, что произойдет, если выйдет из строя система охлаждения ТРАНСТЕКСТА. Бринкерхофф пожал плечами и подошел к окну. - Электроснабжение уже наверняка восстановили. - Он открыл жалюзи. - Все еще темно? - спросила Мидж.
У нас вирус. Я звоню Джаббе. Когда он попытался обойти Стратмора, тот преградил ему дорогу.
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