Reproduction system: Female's Flashcards Preview

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Flashcards in Reproduction system: Female's Deck (57):

What is the difference between oocytes, eggs and ovum?

They are all the same


What are the main female reproductive organs?

Vagina, uterus, Uterine tubes and ovaries


What is the physical description of the vagina?

An elastic muscular tube extending from the cervix to the exterior of the body


What are the functions of the vagina?

Eliminates menstrual fluid, receives the penis during sexual intercourse and holds the spermatozoa before they pass into the uterus


What is the shape of the uterus?

A small pear shaped organ


What is the function of the uterus?

Pathways for sperm transport

provides mechanical protection, nutritional support and waste removal for the developing embryo and fetus

Contracts enabling the fetus to be ejected during birth

Source of menstrual flow


What is the normal and abnormal positioning of the uterus?

Normal = anti flexed (90º angle to the cervix pointing anteriorly)

Abnormal = retroflexed (pointing posteriorly)


Can/how does a retroflexed uterus correct itself?

During child bearing it will go back to be anti-flexed


What is the uterine tube?

A tube that connect the ovaries to the uterus


What is the function of the uterine tube?

Provides a rich nutritive environment for the sperm, oocyte and developing embryo while it transports these into the uterus


What are the two types of cells in the uterine tube? What do each do?

Ciliated and non-ciliated

The ciliated grab the egg and transport it down into the uterus (FYI there is also smooth muscle that perform peristaltic action), the non-ciliated provides nutrients for the egg


What can cause the ciliated cells in the uterine tube to be less effective? What can this lead to?

Women who smoke, are older and have pre-eisting damage in their uterine tube (i.e. from STI's) have cilia that don't beat as much therefore the egg doesn't move down the tube fast enough which can lead to an ectopic pregnancy


What are the ovaries?

Small oval structure at the end of the uterine tube


What is the function of the ovaries?

Stores and maintains the eggs


What is the cervix?

The narrow passage way into the uterus


What does the cervix have in it most of the month and why?

Normally blocked off with a mucosal plug to prevent sperm, bacteria etc. getting into the reproductive tract


What is an old fashioned method for predicting fetal growth?

Some women are able to feel the fundus of their uterus (the top of their uterus) and the height in centimetres is approximately the number of weeks of gestation (FYI greater than usual height may indicate twins, breech birth etc., less than may indicate underdevelopment)


Label the diagram

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What is the endometrium?

The mucosal inner membrane layer of the uterus


What is the structure of the endometrium? What is the function of each component?

Inner functional zone, stratum functionalis (on the inside of the uterus) - Contains most of the uterine glands

Outer basilar zone, stratum basalis (i.e. base of endometrium) - attaches the stratum functionalis to the myometrium


How does the structure of the endometrium change? Why?

In the lead up to ovulation the endometrium develops a thicker stratum functionalis so that the uterus is more well nourished for the potential implantation of an embryo. During menstruation this thicker layer of stratum functionalis is removed

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Label the diagram

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What do the fimbriae of the uterine tube do? How do they do it?

They pick up the oocyte from the ovaries and transport it into the uterine tube

They are covered in beating cilia which pick up the oocyte


Label the diagram, YOU MUST KNOW ALL OF THESE

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FYI not all of these structures are present at once, this is just following the developmental cycle of a primordial follicles to a mature follicle

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What is a primordial follicle?

The oocyte/egg once surrounded by a single layer of flat follicular cells


What are primary follicles?

The primordial follicle when it has grown larger and more columnar in shape


What causes the primordial follicle to develop into a primary follicle?

Follicle stimulating hormone (FSH)


What important structures develops during the primary follicle? What are their functions at this stage?

-Zona pellucide, controls the entry of sperm (i.e. only 1 sperm of the same species)

-Thecal cells, help maintain the shape of the egg


What does a primary follicle develop into? What structures develop?

Develops into a secondary follicle which develops a follicular antrum and the thecal cells develops


How does a follicular antrum develop?

A viscous follicular fluid coalesces to form a single follicular antrum


How do the thecal cells from the primary follicle change in the secondary follicle?

The inner theca become more glandular and develop a blood supply (becomes theca interna) and the outer theca becomes more fibrous developing into a more supportive structure (theca externa)


What important hormone does theca interna produce?



What does the secondary follicle develop into? What happens for this development?

The mature (Graafian or pre-ovulatory) follicle

A single secondary follicle (because many have developed into a secondary follicle FYI) is matures increasing the amount of follicular fluid


How is the mature follicle connected to the ovary?

It is connected to the rim of the peripheral granulose cells by a thin stalk of cells


What happens to the mature follicle?

It undergoes ovulation


What is ovulation?

The follicle ruptures carrying with with it the egg and the surround mass of cumulus cells (fluffy cells surrounding the oocyte/egg)


What causes ovulation?

The increasing size of the follicle and its position in the cortex causes it to bulge from the ovarian surface


What happens to the oocyte after ovulation?

It is collected by the cilia on the fimbria (see diagram for what they are)

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After ovulation what happens to the follicle?

The antrum breaks downs and undergoes luteinisation


What is luteinisation? What happens in this process?

The conversion of an empty follicle cell into a major endocrine gland

The empty follicle becomes highly vascular and forms the corpus luteum (hormone secreting cells)


What hormones are produced by the corpus luteum?



How long does the corpus luteum work for? What happens when it stops working?

For a few weeks if fertilisation is unsuccessful (otherwise longer)

If not utilised then it will degrade into a corpus ablicans where it is reabsorbed back into the stromal tissue of the ovary over months


What enables the corpus luteum to work past its normal life aspen?

Human chorionic gonadotrophin hCG, produced by the chorion of the embryo after about 8 days of fertilisation


How does the uterus respond to high levels of oestradiol?

It develops a thick layer of stratum functionalism (the uterus layer that secretes stuff)


What is the menstrual cycle?

The cyclical process of ovulation


How long does the average menstrual cycle last?

~28 days


What are the three phases of the menstrual cycle?

Menstrual, follicular and luteal phase


What is the menstrual phase?

When the stratum functionalism is removed from the uterus


What is the follicular phase?

Where the follicle is developing leading up to ovulation


What is the luteal phase?

Where the empty follicle is converted into a major endocrine organ for producing progesterone


What part of the menstrual cycle varies the most? How does it vary with age?

The follicular phase varies the most (6-16 days) and gets shorter as the female ages


Why do humans have a menstrual cycle? What do other animals do instead?

Humans have a very thick endometrium layer (i.e. the stratum functionalis) and it needs to be removed, also removes any bacteria that may develop

Most other mammal species re-absorb their endometrium layer


Label the hormones on the diagram

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What is the interaction between Progesterone and Estrogens to Follicle stimulating hormone? What does this mean for the menstrual cycle?

There is a negative feedback loop

As the corpus luteum degenerates (i.e. produces less progesterone) the new primordial follicle begins to develop


The menstrual cycle is a negative feedback loop which allows for the cyclical process of menstruation. When is the exception to this? Explain what is happening?

Just prior to ovulation

At ~day 12 a threshold concentration of estradiol is exceeded and if this is maintained for ~36 hours then is is a oestrogen mediated positive feedback trick for GnRH (gonadotropin releasing hormone) which causes the increased release of LH (Luteinising hormone)


What does an increase in LH lead to (i.e. what important hormone is developed and how? How does this then affect itself?)?

Leads to ovulation resulting in the formation of the corpus luteum which cause increasing progestogen which initiates a negative feedback loop inhibition GnRH which then decreases FSH (follicle stimulating hormone) and LH


Label the diagram

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