In-Depth Analysis of the Human Reproductive System & Fertilisation

This report provides a detailed overview of the human reproductive system, encompassing both male and female anatomy and physiology. It explores the interconnected structures and functions of reproductive organs, highlighting the roles of hormones such as oestrogen, progesterone, and testosterone in regulating reproductive processes. The report also examines the changes occurring in the uterus during the menstrual cycle, the pathways of sperm and ovum during fertilisation, and the potential of IVF in assisting couples with infertility. Furthermore, it delves into the key changes in embryo development during the first eight weeks, the crucial role of the placenta in nutrient and waste transport, and the hormonal regulation of birth and lactation. The report concludes with a comparison of hormonal roles in birth and lactation, providing a comprehensive understanding of the reproductive system's complexities. Desklib provides this assignment solution and many more study tools for students.

The Reproductive
System

Table of Contents
INTRODUCTION...........................................................................................................................1
TASK 1............................................................................................................................................1
a. Male and female reproductive system................................................................................1
b. How the structure and functions of female and male organs link together........................2
c. Effects of oestrogen and progesterone on reproductive system and their impacts.............4
TASK 2............................................................................................................................................5
a.Changes that occur in the uterus during the menstrual cycle..............................................5
TASK 3............................................................................................................................................6
a. Flow chart and explanation of pathway and events that occur as sperm travels from the
male testes to the uterine tube to achieve fertilisation............................................................6
b. Flow chart and explanation of pathway and events that occur as an ovum travels from the
female ovary testes to implementation in the uterus..............................................................6
c. Explanation as how IVF could help the couple in achieving fertilisation..........................7
TASK 4............................................................................................................................................8
a. Key changes that take place in the growing embryo up to the eight weeks.......................8
TASK 5............................................................................................................................................8
a. Role of the placental during pregnancy and its importance in the transport of materials
between mother and baby, and also how it acts as a barrier between them...........................8
b. Why it is recommended that alcohol is not consumed during pregnancy..........................9
TASK 6............................................................................................................................................9
a. How hormones regulate birth.............................................................................................9
b. How hormones regulate lactation.....................................................................................10
c. Comparing and contrasting roles played by each hormone in birth with the role played in
lactation................................................................................................................................10
CONCLUSION..............................................................................................................................11
REFERENCES..............................................................................................................................12

INTRODUCTION
A reproductive system refers a system of sex organs which work all together for the main
purpose of sexual reproduction (Kitazato, N. 2019). In the reproduction system, hormones, fluids
and accessories play an important role. This study is going to show importance and functions
played by each reproduction organs of males and females. Further, it will show importance of
IVF techniques which help couples in achieving fertilisation. It will also show some changes
which occur at the time of menstrual cycle in females. Lastly, this study will discuss roles played
by each hormone in birth as well as changes which occur in the growing embryo up to the eight
weeks.
TASK 1
a. Male and female reproductive system
Figure 1Male reproductive system
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Figure 2: female reproductive system
b. How the structure and functions of female and male organs link together
In the context of female reproductive system and organs, it can be said that it all are being
designed to carry out some important functions. One of the main functions which it plays is
production of female eggs cell which is the most important for reproduction and it is being
known as Ova. There are several organs or parts of female reproduction system which all plays
important functions and all together they help them in reproduction.
Vagina: It refers a canal which plays an important role. In the context of relation or link of
vagina with other organs it can be said that vagina it joins the cervix which is an important lower
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part of uterus, to the outside the body. This vagina is known as birth canal (Rabeeth, M.,
Sakthivel and Janarthanan, 2016).
Uterus: It is one of the important hollow shaped organs in reproduction system. This organ is
known as home to a developing fetus. In the context of link and connection of other organs it can
be said that it has direct link with cervix because cervix is a lower part of Uterus that opens into
vagina. This part is being known as corpus. This organ has capability to expand which helps it
out in holding a developing baby. There is a channel at cervix which allows sperm to enter as
well as menstrual blood to exit.
Ovaries: It can be defined as glands which are in oval shaped. These glands are being located on
one side of the uterus. One of the main important functions of this gland is production of eggs
and hormones (Lessey and Young, 2019).
Cervix: It is the lower part of uterus which opens in vagina. It is made up of strong muscles.
This muscles work as like a channel between vagina and uterus by bringing out menstrual blood
from uterus and throw it out in vagina. As like this it also brings out or allows sperms into uterus
during intercourse.
Oviduct: It is mainly known as fallopian tubes whose main function is to allow sperm cell to the
eggs. Other main role of this organ is it creates an environment which helps women in
fertilization and then transports eggs from ovary in an effective manner.
As like female reproductive organs, male also have some organs which perform several
functions in order to produce and transform sperm.
Penis: It is main male organ shaped in a cylindrical which is being used in sexual intercourse. It
consists of 3 chambers which are in circular shaped. It has 3 parts such as: the root, the shaft and
the glans. All 3 chambers of penis are made up of sponge like tissue which consists of 1000 of
large spaces. It is filled with blood when the man is sexually aroused. Its loose skin allows
penetration and changes the size of penis which blocks urine and only allows semen.
Testes: It is other main organ which are in the shape of oval, lies in the scrotum. One of the main
function of testes is making testosterone which is one of the main and primary sex hormone in
males (Creasy and Chapin, 2018).
Scrotum: It is a loose pouch like sac of skin hangs behind the penis. Its main function is climate
control or protection of testes from fluctuation of temperature
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Epididymis: It is a long coiled tube which is secured at testes. One of the main function of this
organ is to store as well as transport sperms cells which are being preliminary produced in testes.
Vas deferens: It is also a tube made up of strong muscle which travels from Epididymis into the
pelvic cavity and located at behind the bladder.
c. Effects of oestrogen and progesterone on reproductive system and their impacts
In the context of reproduction, it can be said that ovaries or main female organ produces
as well as releases 2 sex hormones which is known as: Estrogens and progesterone. Estrogens are
also being divided into 3 other parts of hormones which plays different functions. Estradiol,
oestrone and estriol are main 3 major estrogens.
Hormones, estrogens and progesterone play several functions in which one of the main
functions is preparing the uterus for completing menstruation process. Important reproductive
hormones in female, estrogens assist in endometrial re growth, calcium absorption as well as
ovulation. It is also stated that it is responsible for secondary sexual characteristic of females.
Secondary characteristics for which it is responsible include: breast development and flaring of
hips. On the other hand, progesterone assists in endometrial re-growth as well as inhibition of
main 2 hormones LH and FSH. FSH hormone is mainly responsible for developing of egg cells.
LH hormone also plays some roles in developing egg cells which is also known as ova (Jeon,
Hwang and Choi, 2016).
In the context of effects of these hormones on reproductive system and female body, it
can be said that if estrogens is taken without progesterone can increase a risk for uterus cancer in
women. But if they are being taken together and work properly than it affects reproductive
system in a positive manner by helping to stimulate the growth of the egg follicle. By stimulating
pituitary gland which is responsible for secretion of other hormones, assist in follicular
development. On the other hand, progesterone is responsible for preparing the wall of the uterus
so that it can allow to accept a fertilize eggs. Some side effects of this hormone on reproduction
system include: cough, anxiety, fatigue and irritability.
Testosterone which is the main male hormone is responsible for the development of male
attributes. It also has several effects on the reproduction system such as: it affects competitive
spirit of their body, Intensity of influencing depend upon the level of testosterone hormone. They
also affect sexual desire of males. Brain is one of the most important part of the body which is
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known as control centre of this hormone production. It houses the pituitary and hypothalamus
gland in their body.
TASK 2
a.Changes that occur in the uterus during the menstrual cycle
Understanding menstrual cycle which is not only limited to periods, is important because
it can affect the female body from the head to toe. Some common changes which occur due at
the time of menstrual cycle are related to hair, skin, mental health, headache and chronic disease.
For knowing changes, it is important to know all main phases of menstrual cycle which are:
Menstrual phase: It is the very first stage of the menstrual cycle when females get periods. This
phase begins when a female egg from the previous cycle is not fertilized. In this phase, females
uterus or eggs releases several tissues and combination of blood. Some changes and effects of
this phase include: mood swings, low back pain, cramps etc.
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Follicular phase: It begins on the first day of period. In this phase, hypothalamus sends a signal
to pituitary gland which release FSH hormone. Among a lot of FSH, only 1 and maturing follicle
sets of a surge in estrogens.
Ovulation phase: It is the phase in which ovary of females’ releases a mature egg. It is the phase
in which female can get pregnant.
Luteal phase: in this last stage of menstrual cycle, the corpus luteal which are formed on the
ovary and secretes many hormones such as FSH. After increasing level of these hormones they
stimulate ovulation (Ikhena and Bulun, 2017).
In the context of changes in all stages or in the uterus it can be said that, the uterus which is a
pear shaped organ, affected a lot at this time. At the time of menstrual phase, uterus sheds its
lining via vagina and for absorbing it they wear tampons. It can also be said that every women
have different menstrual cycle as it varies. Some women get their periods or first phase of
menstrual cycle at the same time each month but some women have irregular menstrual cycle. In
the phase of ovulation, an egg is being released into fallopian tube from ovary.
TASK 3
a. Flow chart and explanation of pathway and events that occur as sperm travels from the male
testes to the uterine tube to achieve fertilisation
There are few organs which plays important role in the pathway of sperm travelling from the
male testes to the uterine which are: seminal vesicle, Vas deferens, Epididymis and testis. Testes
are one of the important organs and place where production of sperm happens in the scrotum.
Epididymis is an effective coiled structure topping the testis.
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Figure 3: Flow chart of Sperm journey
The main function of this is to receive all several immature sperms from the place where all are
being manufactured. After receiving all sperms, it stores all of them for several days. After
ejaculation, sperm is being debarred from Epididymis into deferent duct. Mature sperm than
travel via this duct into pelvic cavity.
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b. Flow chart and explanation of pathway and events that occur as an ovum travels from the
female ovary testes to implementation in the uterus
In the context of pathway of ovum, it can be said that, the whole process of ovum or ova
travelling starts in ovaries which is one of the main female reproductive organ. After that, it goes
to the next organ, called fallopian tubes. These tubes connect the main organs uterus and ovaries.
Uterus is the main female reproduction organ where, fertilized or matured eggs develop into the
fetus.
Figure 4: Journey of Ovum travels
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After this processing and developing of egg, it goes to the cervix (Hoang and Miller, 2017). This
organ also connects vagina and uterus. After reaching egg into uterus, its lining becomes thick in
response to the normal hormones of the reproductive cycle.
c. Explanation as how IVF could help the couple in achieving fertilisation
In vitro fertilization refers an effective technique which is being used to help those
women who face several problems in getting pregnant and make them pregnant. In this
technique, a human egg is being fertilized with several steps with sperm in laboratory. So,
overall it can be said that this techniques is being used for treating infertility as well as some
genetic problems in women. There are several steps by which it can be understood that how this
technique help couples in getting pregnant and achieving fertilisation such as:
Suppressing natural menstrual cycle: In this stage, women who have problem with pregnancy
receive a drug in different forms or a form of daily injection. They get it for approximate of 2
weeks for suppressing their natural menstrual cycle.
Super ovulation: After inserting fertility drugs which contains fertility hormone FSH are being
given to women. This follicle stimulating hormone performs functions of producing eggs. With
the help of vaginal ultrasound scanners, the whole process of ovaries is being monitored.
Retrieving eggs: After monitoring, when the whole process is going in the right track, then with
the help of follicular aspiration process all eggs are collected. In this process, through vagina, a
thin needle is inserted into an ovary. One of the main aims of inserting this needle is because it is
connected to a suction device which helps in sucking eggs out. It is stated that if 15 eggs are
being successfully collected from the ovaries in one cycle than women are more likely to get
pregnant (Crawford and Ledger, 2019).
Fertilization: After collecting all eggs, they all are being placed together with male sperm and
then kept it in an effective environment that has ability to control temperature. After few hours of
keeping eggs in this environment, sperm should enter the egg. Sometimes and in some cases,
sperm are injected directly into the egg. This fertilized egg becomes an embryo.
Embryo transfer: It is one of the critical stage in which embryo is being placed into womb.
Transference of number of embryos depends upon the willingness and capacity of couples and
suggestion of doctors. Normally, more than 1 embryo are being transferred. It is also being done
with the help of a thin tube.
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TASK 4
a. Key changes that take place in the growing embryo up to the eight weeks
In the 8 weeks of pregnancy, baby is referred to as fetus. Legs of fetus from cartilage,
increases in length but some parts of legs such as knees, thigh toes cannot be distinct. Fingers
also started to form, ears also started to being in a shape of shell and eyes are also visible. During
2 weeks, women are referred to be pregnant but in actually yet not pregnant. After 2 weeks of
that, after the 1st day of woman’s last period, doctors count the day of pregnancy. In those 2
weeks, women body make itself prepare for ovulation and then egg is being released. After 2
weeks fertilized egg is moved into fallopian tubes. In the 4-6 weeks, embryo begins to develop
and they create 3 layers. These layers go on the baby’s breathing and digestive system. (Soma-
Pillay and et.al., 2016)
In 6 week, baby’s growth is rapid as heart started to pump blood and so sometimes,
heartbeat can be felt. Some common features of face of the baby also started to form, eyes started
to form. Baby also started to be in a curved shape. By week 7, the embryo can be measured
approximate 10mm and the brain, head and face start to develop rapidly. Inner ear of the baby
also getting started to develop. In the last week of 8, baby is referred as fetus which is already
discussed. This fetus can be measured around 11-14mm in length.
TASK 5
a. Role of the placental during pregnancy and its importance in the transport of materials
between mother and baby, and also how it acts as a barrier between them
Placenta is an important organ which develops at the time of pregnancy in uterus.
Development of this organ is important because it is responsible for providing oxygen as well as
nutrients to developing baby. It is well known that baby take all nutrients from their mother in
womb and it is also important for the baby to release waste products of baby’s blood. Placenta is
the organ who performs this work (Radu and et.al., 2019).
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It is attached to the wall of uterus and baby’s umbilical cord which arises from it. It contains
network of blood vessels which prevents harmful substances in the mother’s blood and act like a
barrier.
b. Why it is recommended that alcohol is not consumed during pregnancy
There are some authors who said that consuming alcohol to the some extent during
pregnancy is quite ok but doctors strictly suggest and recommend women to not consume
alcohol. One of the main reasons of this is it can affect birth and developing a baby. It is stated
that if a pregnant lady have a low level of enzyme or alcohol than there are chances for her baby
to be more susceptible to harm because alcohol may circulate in her body for the long run.
TASK 6
a. How hormones regulate birth
There are some hormones that are responsible for pregnancy and birth of a child such as:
progesterone is one of the main hormones which prevent uterine contractors at the time of
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development of the baby. By decreasing or overriding progesterone hormone in order to creating
labour. Baby enters in the final stretch then it stretches uterus to the extent it can. It requires
physical strain. At the last days of pregnancy, 2 main hormones: corticotrophin releasing
hormone and cortisol increases which helps in giving birth to a baby and the process.
b. How hormones regulate lactation
Lactation refers secretion of milk from mammary glands. In this process, it can be said
that it is being controlled by hormones from some endocrine glands. In the process of secretion
of milk and regulation of lactation, Oxytocin hormone plays an important role as it increases
intramammary pressure by contraction of my epithelial cells. After this contraction, it helps
women in expelling milk from mammary glands (Enjapoori and et.al., 2017).
c. Comparing and contrasting roles played by each hormone in birth with the role played in
lactation
There are several roles are being played by hormones in birth. Each birth hormones play their
separate roles which include:
 Getting body of women ready to give birth.
 Starting labour contractions
 Preparing baby for labour contraction and also for being able to see life outside the body
as they live for 9 months in womb.
 Preparing and telling breast to make milk and getting their baby ready for breastfeeding.
Oxytocin is known as hormone of love as it is involved with fertility, love making as well as
contraction during labour pain and release of milk at the time of breastfeeding. It also makes
women feel happy or triggers nurturing feelings also. It depends upon the level and secretion
of this hormone. As low level of hormone may cause contraction to either stop or slow and
making labour process slow. It may also result in excessive bleeding at placenta. On the other
hand, by being calm and confident, secretion of this hormone can be made balance. It helps
in promoting body’s production of Oxytocin during birth.
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CONCLUSION
From the above case of Jenny it has been summarized that hormones like estrogens,
testosterone and progesterone played a vital role in reproduction system. These hormones are
liable for pregnancy in women. It has also shown process of sperm travels from the male testes
and ovum travels from the female ovary testes and how this process make a couple able in
getting pregnant After that, this study has also shown impotence of IVF techniques and steps as
how it makes a couple able in getting pregnant. It has also shown functions of each organ of
reproduction system of males and females.
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REFERENCES
Books & Journal
Crawford, G.E. and Ledger, W.L., 2019. In vitro fertilisation/intracytoplasmic sperm injection
beyond 2020. BJOG: An International Journal of Obstetrics & Gynaecology. 126(2).
pp.237-243.
Creasy, D.M. and Chapin, R.E., 2018. Male reproductive system. In Fundamentals of
Toxicologic Pathology (pp. 459-516). Academic Press.
Enjapoori, A.K. and et.al., 2017. Hormonal regulation of platypus Beta-lactoglobulin and
monotreme lactation protein genes. General and comparative endocrinology. 242.
pp.38-48.
Hoang, H.D. and Miller, M.A., 2017. Sperm navigation mechanisms in the female reproductive
tract. In Signaling-Mediated Control of Cell Division (pp. 241-267). Springer, Cham.
Ikhena, D.E. and Bulun, S.E., 2017. Uterine fibroids and the endometrium. In The Endometrial
Factor (pp. 120-129). CRC Press.
Jeon, S.Y., Hwang, K.A. and Choi, K.C., 2016. Effect of steroid hormones, estrogen and
progesterone, on epithelial mesenchymal transition in ovarian cancer development. The
Journal of steroid biochemistry and molecular biology. 158. pp.1-8.
Kitazato, N., Saturn Licensing LLC, 2019. Content reproduction apparatus, control information
providing server, and content reproduction system. U.S. Patent 10,171,546.
Lessey, B.A. and Young, S.L., 2019. Structure, function, and evaluation of the female
reproductive tract. In Yen and Jaffe's Reproductive Endocrinology (pp. 206-247).
Content Repository Only!.
Rabeeth, M., Sakthivel, T. and Janarthanan, S., 2016. The internal reproductive organs of
Lygaeid bug, Spilostethus pandurus (Heteroptera: Lygaeidae)-gross morphology and
histomorphology. Journal of Entomological Research. 40(4). pp.347-356.
Radu, I. and et.al., 2019, November. Parents’ experience of risk and health recommendations for
alcohol consumption during pregnancy and breastfeeding. In Swiss Public Health
Congress 2019, Neuchatel, Schweiz, 7. November 2019.
Soma-Pillay, P. and et.al., 2016. Physiological changes in pregnancy. Cardiovascular journal of
Africa. 27(2). p.89.
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