human reproduction project file class12

1. BIOLOGY
PROJECT FILE
CLASS-12-
SCIENCE

2. SCHILLER SENIOR SECONDARY
SCHOOL
NAME :-ADITI MALIK
CLASS:-12TH SCIENCE
ROLL NO.-----
SUBJECT:-BIOLOGY
TOPIC :- HUMAN
REPRODUCTION AND
REPRODUCTIVE HEALTH
SUBMITTED TO:-
SHRAMIKA SURABHI
SUBMITTED BY:- ADITI MALIK

3. INDEX
introduction of human
reproduction
male reproductive system
female reproductive system

4. ACKNOWLEDGEMENT
I would like to express my special
thanks of gratitute to my teacher Mrs.
shramika surabhi ma'am who give me
the golden opportunity to do this
wonderful project on the topic human
reproduction and reproductive health
which also helped me in doing a lots of
research and i came to know about so
many new things i am really very
thankful.
secondly i would like to thank my
parents and friends who helped
me a lot in finalizing this project
within the limited time frame
submitted by-aditi malik submitted to :-Mrs. shramika surabhi

5. CERTIFICATE
this is to certify that aditi
malik of class-12th science
has successfully completed
this biology project on the
topic human reproduction
and reproductive health
prescribes by mrs. shramika
surabhi ma'am during the
academic session 2022-2023 as
per the guidelines issue by
the central board of
secondary education.
external examiner

7. WHAT IS REPRODUCTION
Reproduction can be defined as the
biological process of producing a new
individual or an offspring identical to the
parents. This process ensures the increase in
the number of individuals of a species when
conditions are favourable. It is one of the
fundamental characteristics of living things
and an essential life process.
TYPES OF REPRODUCTION
There are two types of reproduction – asexual and
sexual.
Sexual Reproduction –This process of
reproduction is very complex that involves the
formation and transfer of gametes, followed by
fertilization, the formation of the zygote, and
embryogenesis.
Asexual Reproduction — This process of
reproduction involves only one parent and the
new offspring produced is genetically similar to
the parent.

8. ........about human reproduction......
human beings undergo a sexual mode of reproduction. .
In human beings, both males and females have different reproductive
systems; hence, they are known to exhibit sexual dimorphism.
Whether the zygote develops inside or outside gives us two kinds of
organism termed as oviparous if fertilization occurs outside the body
and viviparous if it occurs inside. Humans are viviparous by nature as
we directly give birth to the baby instead of laying eggs. Since humans
are one of the most advanced species, reproduction is highly
complicated. It involves multiple processes sequentially, each more
fascinating than the next.
Human reproduction takes place by the coordination of the male and
female reproductive systems. In humans, both males and females have
evolved specialized organs and tissues that produce haploid cells, the
sperm and the egg. These cells fuse to form a zygote that eventually
develops into a growing foetus. A hormonal network is secreted that
controls both the male and female reproductive systems and assists in
the growth and development of the foetus or the baby.....
INTRODUCTION OF HUMAN
REPRODUCTION
the formation of gamete is
called -gametogenesis
formation of male gamete is
known as -spermatogenesis
male gamete-sperm
formation of female gamete-oogenesis
female gamete-ova or egg

9. transfer of sperm into female
genital tract is called insemination
fusion of male and female
gamete is called-
fertilisation
formation and development of
blastocyst to the uterine wall is
called implantation
embryonic development-
gestation
delivery of baby-
parturition
sperm formation
continue in old
men, but the
formation of the
ovum ceases in
the women
around the age
of fifty years.

12. testes-pair of the testes is present in the scortum
that is to keep outside the body to safeguard against
the excessive heat of the human body and maintain
the optimum temperature of 2-2.5 degree celsius
lower than the normal body temperature. a total of
250 testicular lobules are there ,where each lobule
contain the two-three seminiferous tubules where
the sperm are created.
Two types of cells are present in the internal lining of
the seminiferous tubule :-
spermatogonia-germ cell of male that undergo
meiotic division to form sperms
sertoli cells-they provide the nutrition to the germ
cells
it also secrete the AMF(ANTI MULLERIAN FACTOR )-
inhibits the formation of fallopian tube and the
uterus in males
leydig cells or interstitial cells are also present in
interstitial space outside the seminiferous tubule
that produce and secrete androgens(male and
reproductive hormones
male reproductive system
primary sex organ:-
paired testes
secondary sex organs
accessory ducts
glands
external genetalia

13. accessory ducts:- vasa efferentia, rete
testis, epididymis and vas deferens are the
four accessory ducts present their job is to
store and transport the sperm to the
urethra. vas deferens with the ducts from
seminal vesicle function as an ejaculatory
duct that open into the urethra
testes descend from the abdomen
through the inguinal canal to the scortum
in the 7th month of pregnancy because
the testes produce a hormone in the 7th
month -testosterone-responsible for
testes descend
if testes fail to descend from the
abdomen cavity to the scortum so this
can lead to criptorchidism
*hitler suffered from criptorchidism
glands :-prostate gland ,a pair of seminal
vesicle and the bulbourethral glands or
cowper's gland are the three glands that are
responsible for the secretion of the seminal
plasma that is rich in certain enzymes,
calcium and fructose and also provide
lubrication to the penis

14. SPERMATOGENESIS
STARTS AT THE PUBERTY .THERE IS
INCREASE IN THESECRETION OF GNRH
(GONADOTROPIN RELEASING
HORMONES) FROM THE
HYPOTHALAMUS.GNRH STIMULATES
THE PITUITARY TO SECRETE LH
(LUTEINIZING HORMONES) AND FSH
(FOLLICLE -STIMULATING HORMONES)
LH STIMULATES THE LEYDIG CELL TO
SECRETE THE ANDROGEN
.TESTOSTERONE AND
ANDROSTENEDIONEARE THE MAIN
ANDROGEN THAT STIMULATES IN THE
PROCESS OF THE SPERMATOGENESIS
FSH STIMULATES THE SERTOLI
CELLSTO SECRETE THE FACTOR FOR
HELPING IN THE PROCESS OF
SPERMIOGENESIS

16. .spermatogonia are diploid (2n=46) and
divide by the mitotic division to form
multiple cells called primary
spermatocytes
.each primary spermatocyte cell divide
meiotically to first form two haploid
(n=23)secondary spermatocytes that are
equal in size.
.secondary spermatocytes further divide
in the 2nd meiotic division to form the
haploid spermatids of equal size
.so each diploid primary spermatocyte
cell forms four haploid spermatids.
.spermiogenesis is the process of
formation of sperms from the
spermatids.
.the process of releasing of sperm from
the seminiferous tubule is termed as
spermiation.

18. STRUCTURE OF SPERM
semen consists of seminal plasma and
sperms. at a time ,200-300 million sperms
are ejaculated at once. the head contains the
acrosome apically , which contains enzymes
that facilitate the entry of sperm into the
ovum . it is followed by an elongated nucleus
(haploid)
the middle piece has multiple
mitochondria that deliver the energy
for the sperm's movement.
the tail is a flagellum that protrudes
out of the cell body and is responsible
for the vigorous motility of sperms,
the tail helps sperm in swimming to
reach towards the ovum

21. FEMALE REPRODUCTIVE
SYSTEM
primary sex
organs
pair of ovaries
secondary sex organs
pair of oviducts /fallopian tube
uterus
cervix
vagina
external genetalia
mons pubis
labia majora
labia minora
clitoris
cervix opening
vagina opening
ovaries:-two ovaries are present in the female
responsible for producing the ovum and reproductive
hormones. the peripheral cortex is present at the
periphery of the ovarian stroma and the inner
medullary region

22. Perimetrium: Outermost membranous layer
Myometrium: Middle layer consisting of smooth
muscles that give strong contractions because of the
myometrium during the delivery
Endometrium: Glandular layer where blastocyst is
embedded for development. It undergoes cyclic changes
during the menstrual cycle.
fallopian tube or oviduct-a pair of fallopian or oviducts
help to connect the ovaries to the uterus
the infundibulum is the funnel -shaped part of the fallopian
tube near the ovary and terminates into finger-like
projections known as fimbriae. which collects the ovum ,it
leads to the uterus through the ampulla and isthmus.
Uterus or womb: An inverted pear-shaped region where the
embryo develops. Its walls are made up of three layers:
A narrow cervix connects the vagina and the uterus.
Together the vagina and cervical canal constitute the birth
canal.
External Genitalia: Mons pubis (fatty tissue), labia majora
and labia minora (tissue folds) and clitoris form external
female genitalia along with the hymen membrane that
protects the vaginal opening.
Mammary glands: Pair of breasts that contain fat and
mammary glands. Alveolar cells secrete milk.

24. Ovary of the fetus only forms around
two million oogonia.
Oogonia divide further mitotically and
enter prophase-1 of meiotic division. At
this stage, the division stops temporarily,
and the cells are called primary oocytes.
Primary oocytes get surrounded by
granulosa cells to form primary follicles.
Only 60,000 to 80,000 primary follicles
are left at puberty, as most have
degenerated.
Primary follicles develop into
secondary and tertiary follicles,
containing a fluid-filled cavity
known as the antrum.
Oogenesis
It is the formation of a mature female
gamete called the ovum. It differs from
spermatogenesis as It begins during
embryonic development, unlike
spermatogenesis, which starts only at
puberty.

25. THE FIRST MEIOTIC DIVISION OF PRIMARY
OOCYTES OCCURS INSIDE THE TERTIARY
FOLLICLE. IT IS AN UNEQUAL DIVISION LEADING
TO A LARGE HAPLOID SECONDARY OOCYTE,
WHICH IS LARGE AND HAS A TINY POLAR BODY.
THE TERTIARY FOLLICLE CHANGES INTO THE
GRAAFIAN FOLLICLE (MATURE FOLLICLE). THE
MEMBRANE ZONA PELLUCIDA DEVELOPS
AROUND THE SECONDARY OOCYTE.
OVULATION IS THE PROCESS BY WHICH THE
OVUM (SECONDARY OOCYTE) IS RELEASED ON
THE RUPTURE OF THE GRAAFIAN FOLLICLE.

26. Menarche: First menstruation at
puberty
The menstrual cycle is 28/29 days on average, and an ovum is released at the middle of each cycle (~14th day).
Lack of menstrual cycle indicates
pregnancy or may be due to poor
health or stress.
Menopause is the stage at which
the menstrual cycle ceases (~45-
50 yrs). A female’s reproductive
phase is between menarche and
menopause, whereas males
continue to produce sperm
throughout their lives.
Menstrual Cycle

27. Menstrual phase: Day 1, uterus lining which
is prepared for implantation starts to shed
which lasts 3 to 5 days.
Follicular phase: In this phase, the primary
follicle starts developing into a mature
Graffian follicle. The endometrium also starts
proliferating. The uterus starts preparation
for another pregnancy.
Ovulatory phase: Mid-cycle phase, this is
the phase in which ovulation takes place i.e.,
day 13-17. The end of the follicular phase
along with the ovulation period defines the
fertilisation period.
Luteal phase: It is the post-ovulation phase,
where the fate of the corpus luteum is
decided. If fertilisation occurs, pregnancy
starts. If fertilisation doesn’t occur, it marks
the onset of another cycle.
The menstrual cycle is divided into four phases,
namely:
1.
2.
3.
4.

29. NOTE*-THE PITUITARY RELEASES
GONADOTROPINS (LH AND FSH) WITH A
GRADUAL INCREASE IN THEIR LEVEL TO
STIMULATE FOLLICULAR DEVELOPMENT. IN
THE MIDDLE OF THE CYCLE, THE LEVEL
REACHES ITS PEAK, AND LH INDUCES THE
RUPTURE OF THE GRAAFIAN FOLLICLE.

31. OCCURS AT THE AMPULLARY REGION OF THE FALLOPIAN TUBE
ONCE A SPERM COMES INTO CONTACT WITH
THE ZONA PELLUCIDA OF THE OVUM, IT
INDUCES CERTAIN CHANGES IN THE
MEMBRANE TO PREVENT THE ENTRY OF ANY
FURTHER SPERM
ENTRY OF SPERM INDUCES THE
SECOND MEIOTIC DIVISION OF THE
SECONDARY OOCYTE THAT FORMS A
LARGE OOTID (HAPLOID) AND THE
SECONDARY POLAR BODY.
THE SPERM AND OVUM FUSE
TOGETHER TO FORM THE
DIPLOID ZYGOTE.
FERTILIZATION
THIS STAGE IS RESPONSIBLE
FOR THE SEX OF THE BABY.

32. spermatogenesis involves the
formation of male gametes with
either the X chromosome or the
Y chromosome. The zygote
develops into a female if the X
chromosome containing sperm
fuses with the ovum, else it
develops into a female if the Y
chromosome containing sperm
fuses with the ovum.
The zygote divides mitotically,
forming blastomeres, and
moves towards the uterus
through the oviduct.

33. NOTES
Morula is the stage with 8-16 blastomeres in the embryo.
The continuous division after the morula stage forms the
blastocyst. The blastomeres that arrange themselves in the
outer layer are termed trophoblast, and those on the inner
cells lead to the formation of the inner cell mass.
The trophoblast gets attached to the uterus’s endometrium
lining, and the inner cell mass gets differentiated into the
embryo.
Implantation is the start of pregnancy, which includes
embedding the blastocyst in the endometrium when the
dividing uterine cells completely cover it.
implantation
Stages of Embryo Development

35. Parturition
It is the process of childbirth that is
initiated by neuroendocrine signals.
Once the foetus is completely
developed, mild uterine contractions
start to occur, followed by oxytocin
secretion from the pituitary gland. As
more and more oxytocin is secreted,
the contractions become stronger in
strength and lead to childbirth. The
placenta is also delivered after the
infant. Nowadays, the umbilical cord is
cut and preserved for stem cells that
can help cure future diseases for the
person and the immediate family
members.

36. Doctors often inject oxytocin to
help induce delivery.
Lactation: Mammary glands start
milk production due to increased
prolactin secretion from the
pituitary gland.
Colostrum: First formed
(yellowish) milk from the
mammary glands is rich in
antibodies and proteins and
essential for the immunity of
infants.