Reproductive Flashcards
What are the functions of the reproductive system?
Ensures perpetuation of species , without this system, species become extinct
What are the 3 reproductive processes and what are they controlled by?
Formation of gametes, fertilisation and lactation. They are controlled by the interaction of hormones and the nervous system
What is the function of the female reproductive system?
It is more complex due to the nurture aspect. Produces ova and includes mammary glands
What structures are included in the female reproductive system?
Ovaries, uterine tubes, uterus, vagina and vulva
The female reproductive system produces ova (egg) which allows for?
Accepts sperm from penis, provides a suitable place for the embryo to develop and provides nourishment for the infant
What are ovaries and where are they located?
They are paired organs found close to the lateral walls of the pelvic cavity below the kidneys. They are held in place by various connective tissue ligaments that blends with the broad ligament that supports the uterus and vagina. They are about 3cm long and oval shaped surrounded by a fibrous tunica (membrane) that blends in with the peritonium
What are the 2 regions of the ovaries?
An inner medulla and outer cortex
What does the medulla of the ovary contain?
Loose connective tissue, blood, lymph vessels and nerves
What does the outer cortex of the ovary contain?
Connective tissue (stroma) which contains eggs or ova in various stages of maturity. Is heavily vascular and where follicles are located. At final stage (1 month) ovulation occurs and ovary surface bulges out and ruptures which transforms follicle into corpus luteum
What are the uterine tubes and where are they located?
Known as fallopian tubes or oviducts. Each tube is laden with smooth muscle and is about 12cm long. Attached to the uterus at one end
What does the inner lining of the oviduct consist of?
Ciliated mucous membrane that helps both move and nourish not only the ova but also the sperm
What are the 3 regions of the oviduct?
Ampulla (largest part of the tube and where fertilisation usually takes place), Isthmus (narrow portion near uterus) and Intramural passageway (where it connects with the uterus)
What does the free end (infundibulum) of the oviduct tube consist of?
It is funnel shaped with long finger like projections called fimbrae. They are distal end and do not connect to ovary but have a space (part of peritoneal cavity). When ova released it goes into cavity where the fimbrae create wave like patterns to move it towards tube (ectopic pregnancy is casting into cavity)
What occurs in ovulation day 9-19?
Cervix opens allowing sperm in
What is the uterus and where is it located?
It is a wide thick walled tube about 7.5cm long and 5cm at its widest part (varying on number of pregnancies). Lies in bottom of pelvic cavity anterior to the rectum and posterior to the bladder and held in place by many ligaments, through the pelvic floor muscles are the major support. Collapsing is know as prolapse
What are the regions of the uterus called?
Main part is the body, rounded portion at the top is fundus and lower narrow part is the cervix which connects to the vagina
What is the role of the uterus?
To receive, retain and nourish the ova
What are the 3 layers of the uterus?
Serosa(perimetrium), Myometrium and Endometrium
What does the serosa layer of the uterus consist of?
Outer layer connects the uterus to the peritoneum
What does the myometrium layer of the uterus consist of?
Middle layer. 3 poorly defined layers of smooth muscle to help in childbirth
What does the endometrium layer of the uterus consist of?
Inner layer, during monthly preparations for pregnancy, layer becomes thick and vascular (important as these arteries de and regenerate each cycle). Two parts- superficial (functional) layer that is sloughed during menstruation and deep basilar layer which reforms the functional layer after menstruation
What are the 3 stages of the menstrual cycle?
Menstrual phase, Proliferative phase and Secretory phase
What occurs in the Menstrual phase of the menstrual cycle?
Days 1-5. Functional layer is sloughed off and decreased ovarian hormones though by day 5, follicle stimulating hormone has increased and the new follicle starts to increase oestrogen levels
What occurs in the proliferative phase of the menstrual cycle?
Days 6-14. Endometrial build up which both stimulates and stimulated by elevated oestrogen. Glands and blood vessels increased. Progesterone receptors are readied and ovulation occurs on day 14 in response to a quick release of luteinising hormane. The lutienising hormone also converts the ruptured follicle into corpus luteum
What occurs in the secretory phase of the menstrual cycle?
Day 15-28. Endometrium prepares for embryo implantation. Progesterone levels rise from the corpus luteum. Nutrients are built up in the endometrial lining. If there is no fertilisation then the corpus luteum degrades and luteinising hormone and progesterone levels decline. Without the hormones the area is deprived of nutrients and oxygen leading to a functional layer sloughing.
What occurs when Follicle stimulating hormone is elevated?
Causes infertility
What is the vagina and where is it located?
Elastic, muscular tube lies anterior to the rectum and posterior to the urethra and bladder. Contains lots of antigen presenting cells and extends from the cervix to outside of the body.
What does the inner lining of the vagina contain?
Many folds called rugae which allows the vagina to enlarge during sexual intercourse and childbirth
How is the vagina lubricated?
From the cervix mucous glands
What do the cells in the vagina release?
Glycogen that is anaerobically metabolise to become lactic acid which then leads to a highly acidic/protective envrionment
Where are the mammary glands present?
In both sexes and become functional only in females
What is the role of the mammary glands?
To produce milk to nourish a newborn baby and are only important once reproduction has only become accomplished
What causes the female mammary glands to increase in size at puberty?
Stimulation by female sex hormones especially oestrogen
What are the mammary glands contained within?
The rounded skin covered breasts anterior to the pectoral muscles of the thorax. Slightly below the centre of each breast is a pigmented area called the areola which surrounds a central protruding nipple
Internally what does each mammary gland consist of?
15-20 lobes which radiate around the nipple. These lobes are padded and separated from each other by connective tissue and fat
What does each lobe from the mammary glands contain?
Smaller chambers called lobules which contain clusters of alveolar glands that produce milk when a women is lactating (producing milk). These glands and ducts are generally underdeveloped until pregnancy. Size is due to fat deposits
How does milk pass through the breast?
The alveolar glands of each lobule pass the milk into the lactiferous ducts which open to the outside at the nipple
What happens prepuberty to the hypothalamus in females?
Small amounts of oestrogen released inhibit the hypothalamus’ release of Gonatropin Releasing hormone/
What happens post puberty to the hypothalamus in females?
They hypothalamus becomes less sensitive to oestrogen and starts to release Gonotropin Releasing Hormone which stimulates the anterior pituitary to release Follicle Stimulating Hormone and Luteinising Hormone
What does the follicle stimulating hormone in females?
The anterior pituitary secretes follicle stimulating hormone which stimulates development of follicles in the ovary and the secretion of oestrogens by the follicle itself
What does the luteinising hormone do in females?
Luteinising hormone is secreted by the anterior pituitary. It stimulates the final stages of follicle maturation the production of oestrogens and progesterone, and ovulation. Also the development of corpus luteum.
How many years does it take for hormones to stabilise?
Takes up to 3 years post 1st menarche
What is oestrogen and what is it secreted by?
It is a group of hormones secreted by the theca cells of the follicle, the corpus luteum and placenta
What are the 5 roles of oestrogen?
Growth of sex organs, growth of the follicles, growth of the endometrium, stimulation of peristalsis in the uterine tubes and changes to the cervical mucous to a more favourable alkaline pH to ensure sperm survival.
What is progesterone secreted by?
Secreted by corpus luteum and placenta
What is the function of progesterone?
Completes growth of endometrium, stimulates growth of lobules in mammary glands and prepares uterus for pregnancy
What are the anatomical features of the male reproductive system?
Testes, scrotum, spermatic cords, epididymis, ductus deferens, urethra, accessory glands and penis
What is the sequence of the male reproductive system?
Testes, ducts, epididymis, ductus deferens, ejaculatory duct, urethra
What is the function of sperm cells?
To produce sperm cells and deliver them to the female
What nervous system is the male reproductive system controlled by and specifically what functions and how is it done?
Controlled by ANS. The PSNS controls the erection and the SNS controls the ejaculation and is done via a spinal reflex (L1/L2) based on afferent/efferent
What are the testes?
Paired glands which are oval in shape. About 4-5cm long and 2.5 cm wide. Covered by 2 parts; the outer from the peritoneum and the inner by thick, white capsule of CT which extends into interior of the testes and divides it into partitions
What do the testes produce?
Spermatozoa and testosterone
What does the septa in the testes do?
Extension of partitions which separates the testes into 250-300 cone shaped lobules
What do the lobules in the testes contain?
1000 semineferous tubules that produce sperm (factories).
Where do the tubules of the testes go?
Into another tubule (rectus) to another network of tubules (rete testis) into ducts then to the epididymis
What surrounds the epididymis?
Smooth muscle cells that rhythmically contract and may help to propel sperm
What do Leydig cells do?
They produce testosterone(different to sperm)
Where is the scrotum located?
Cavity continuous with abdominal cavity in which testes descend into scrotum before birth through the inguinal canals, IT is divided by septa into 2 cavities. Skin covering is very thin and contains a number of sweat glands and sits outside the body
Why does the scrotum sit outside the body?
To lower temperature by 2 degrees to favour sperm production (37 is best)
What is the scrotum supported by and what is it reliant on?
Supported by cremaster (from internal obliques) and dartos muscles (lifts and drops scrotum). It is also heavily reliant on blood flow to control temperature
What does the spermatic cord do?
Conduction of sperm and vascularity
What does the spermatic cord contain and what is it used for?
Arteries, veins, nerves and the conducting tubes are contained within the cord. The sperm is transported to outside of the body through a series of conducting tubes
What is vasectomy?
The cutting of the spermatic cord
What does the epididymis do?
Storage and maturation of sperm cells
What is the epididymis?
A large number of small ducts exciting from the testis and passing into a large, single coiled tube wh
Where is the epididymis located?
Lies along the posterolateral side of the testes. Main body of the spididymis more than 6 metres so very coiled to fit into small spaces in testes
What is the continuation of the epididymis?
Into the ductus deferens
What does the epididymis store?
Storage area of sperm cells allowing them to mature
What cells are the epididymis made from?
Constructed of psuedo stratified epithelial cells that help at both a nutrient and antimicrobial level
How long does it take to go through the epidiymis?
takes around 20 days and is where sperm learn to swim
What happens that is stored longer than a few months?
Usually phagocytized
What is the ductus deferens?
Sperm duct
What is the role of the ductus deferens?
Muscular duct passes from the scrotum to the ejaculatory duct through the inguinal canal into the pelvic cavity where it loops around the ureter and joins at the ejaculatory gland into the prostate and urethra
What is the urethra and its role?
The ejaculatory duct joins the sperm duct to the urethra which opens to the outside of the body. Sperm and urine leave the body through the urethra although not at the same time
What do the accessory glands do in the male reproductive system?
Assist nourishment, enhance motility and protect sperm. These are the glands located around the urethra as it emerges from the bladder
What do seminal convoluted vesicles do?
Produce sperm (alkaline) that nourishes sperm when they leave the body on the posterior bladder and thick muscle layers
What is semen?
60% seminal fluids, 40% prostate fluid with hormones; relaxin and prostaglandins which helps sperm motility and fertilising power
What do the prostate glands do?
Secreted a thick, milky, acid secretion that helps sperm motility
What do Bulbourethral glands do?
Secrete fluid that neutralises acidity in the urethra and lubricates the penis
What is the penis?
It consists of a long shaft that enlarges to form an expanded tip called the glans penis which contains many sensory nerves and blood vessels
How long is the penis?
It is about 9cm long when relaxed erect (due to 3 layers of erectile tissue and a lot of dense CT) the penis may enlarge to 16cm
What is foreskin or prepuce?
Covered by loose fitting skin
What is the main role of the penis?
To allow sperm to be deposited in the vagina
When does spermatogenesis start and where?
Begins at puberty and in the seminiferous tubes
Every day how many sperm are produced per day?
Approx 400 million sperm
What does the seminiferous tube contain?
Spermatogenesis, mitochondria and golgi apparatus
What occurs when developing sperm cells mature?
They move towards the lumen of the tubules
How do the sperm learn to swim?
Takes 64-72 days and they cannot swim but learn after being pushed into the epididymis and in this journey become specialised
What are the parts of a sperm?
A head, mid piece and tail
What is found in the head of the sperm?
The nucleus
What occurs at the tip of a sperm?
An acrosome (contains enzymes) is formed from the golgi complex.
What does the acrosome produce?
Enzumes which help to dissolve the material surrounding the egg cell during fertilisation
What does the mid piece of the sperm contain?
A large number of mitochondria which provide the energy needed to move
What is the role of the tail of the sperm?
Move backwards and forwards to propel the sperm forward
What temperature does the production and naturation of the sperm require?
37 degrees
What is the process of spermatogenesis and the development of the sex organs controlled by?
Hormones called androgens which are mainly produced by interstitial cells in the tubules
What is the most abundant male reproductive hormone?
Testosterone
Where is testosterone produced?
In the testes usually from the onset of puberty
How is testosterone produced?
In puberty, follicle stimulating hormone stimulates semineferous tubules to produce sperm. Leutenising hormones stimulates intersistial cells and testosterone is produced continuously. It stimulates primary and secondary sex characteristics
What are the primary male sex characteristics?
Testosterone stimulates maturation of reproductive organs and underlies sex drive
What are the secondary male sex characteristics?
Deepening of voice (larynx enlarges), increased hair growth, enlargement of skeletal muscle and thickening of bone
