The Uterus Flashcards
What are the physical characteristics of the uterus?
- hollow
- pear-shaped
- thick-walled
- muscular
Where is the uterus situated?
- between the bladder and the rectum
What happens to the uterus during and after pregnancy?
- during pregnancy it enlarges considerably
- soon after birth it almost returns to its original size
What is the lower part of the uterus called?
- the cervix
Where does the cervix go?
- it projects into the vagina
How large is the opening of the cervix normally?
- normally only millimetres in diameter
Why does the cervix have an opening (aside from to birth a child)?
- to allow menstrual blood to leave the body
- and sperm to gain access
What keeps the uterus closed during pregnancy and why?
- the sphincter muscles of the cervix
- to prevent a miscarriage
What does the uterine wall consist of?
- myometrium
- endometrium
What is the myometrium?
- a thick, involuntary muscle layer of the uterine wall
What is the endometrium?
- a lining of the uterine wall that is richly supplied with blood vessels
Why do the walls of the uterus need to be thick?
- so that it can stretch when a baby develops inside it
What happens to the endometrium at ovulation?
- progesterone causes the endometrium to thicken
- to prepare for the implantation of the blastocyst
What happens to the endometrium if fertilisation does not occur?
- the upper layer of the endometrium becomes detached
- and is passed out together with the unfertilised egg
- (menstruation)
What are the functions of the uterus?
- The uterus is the organ in which the blastocyst implants, develops and grows
- The contraction of the myometrium enables the baby to be pushed out during birth
What does the myometrium do?
- contracts to enable the baby to be pushed out during birth