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Chapter 13

The Reproductive System

Class 10 - Selina Concise Biology Solutions


Multiple Choice Type

(Select the most appropriate option in each case)

Question 1

Which one of the following is the correct route that a sperm follows when it leaves the testis of a mammal?

  1. Vas deferens → epididymis → urethra
  2. Urethra → epididymis → vas deferens
  3. Epididymis → urethra → vas deferens
  4. Epididymis → vas deferens → urethra ✓

Question 2

When pregnancy does not occur, the life of corpus luteum is about:-

  1. 4 days
  2. 10 days
  3. 14 days
  4. 28 days ✓

Question 3

In female, how much time after fertilization, does the fertilized egg get implanted in the uterine wall?

  1. Few months
  2. One month
  3. Three weeks
  4. About seven days ✓

Question 4

The middle piece of sperm provides:

  1. energy ✓
  2. food
  3. gene
  4. chromosomes

Question 5

The normal gestation period in humans is:

  1. 270 days
  2. 290 days
  3. 280 days ✓
  4. 295 days

Very Short Answer Type

Question 1

Name the following:

(a) The membrane which protects the foetus and encloses a fluid.

(b) The canal through which the testes descend into the scrotum just before birth in human male child.

(c) Uterine wall that is shed during menstruation.

(d) The minute finger-like projections of placenta.

Answer

(a) Amnion

(b) Inguinal canal

(c) Endometrium

(d) Villi

Question 2

Rewrite the terms in the correct order so as to be in a logical sequence.

(a) Implantation, ovulation, child birth, gestation, fertilization.

(b) Coitus, ovum, sperm, sperm duct, urethra, vagina.

(c) Sperm duct, penis, testes, sperms, semen.

(d) Puberty, menopause, menstruals, menarche, reproductive age.

(e) Graafian follicle, Ostium, Uterus, Fallopian tube.

Answer

(a) Ovulation → fertilization → implantation → gestation → child birth

(b) Sperm → sperm duct → urethra → coitus → vagina → ovum

(c) Testes → Sperms → Sperm duct → Semen → Penis

(d) Reproductive age → Puberty → Menarche → Menstruals → Menopause

(e) Graafian follicle → Ostium → Fallopian tube → Uterus.

Question 3

Give appropriate terms for the following processes:

(a) The onset of reproductive phase in a female.

(b) Rupture of follicle and release of ovum from the ovary.

(c) Monthly discharge of blood and disintegrated tissues in human female.

(d) Process of fusion of ovum and sperm.

(e) Fixing of developing zygote (blastocyst) on the uterine wall.

Answer

(a) Menarche

(b) Ovulation

(c) Menstruation

(d) Fertilization

(e) Implantation

Question 4

Match the items in column I with those in column II and write down the matching pairs (some may not match)

Column IColumn II
(a) Acrosome(i) An embryo which looks like human baby
(b) Gestation(ii) Luteinizing hormone
(c) Menopause(iii) Ovum producing cells
(d) Foetus(iv) Semen
(e) Oogenesis(v) Spermatozoa
(f) Ovulation(vi) Complete stoppage of menstrual cycle
 (vii) Time taken by a fertilized egg till the delivery of baby

Answer

Column IColumn II
(a) Acrosome(v) Spermatozoa
(b) Gestation(vii) Time taken by a fertilized egg till the delivery of baby
(c) Menopause(vi) complete stoppage of menstrual cycle
(d) Foetus(i) An embryo which looks like human baby
(e) Oogenesis(iii) ovum producing cells
(f) Ovulation(ii) Luteinizing hormone

Question 5

Name the following:

(a) The body part in which the testes are present in a human male.

(b) The part where the sperms are produced in the testes.

(c) The fully developed part of the ovary containing a mature egg.

(d) The accessory gland in human males whose secretion activates the sperms.

(e) The tubular knot fitting like a cap on the upper side of the testis.

Answer

(a) Scrotum

(b) Seminiferous Tubules

(c) Graafian Follicle

(d) Seminal vesicle

(e) Epididymis

Question 6

Choose the odd one in each of the following:

(a) Oestrogen; progesterone; testosterone; prolactin

(b) Ovary; fallopian tube; ureter; uterus

(c) Seminiferous tubule; ovum; epididymis; sperm duct; urethra

(d) Sperm; implantation; fertilization; ovum; after birth

(e) Relaxin; cervix dilates; amniotic sac ruptures; child birth; follicle.

Answer

(a) Testosterone is the odd one here because Oestrogen, progesterone and prolactin are female reproductive hormones whereas Testosterone is a male reproductive hormone.

(b) Ureter is the odd one here because Ovary, fallopian tube and uterus belongs to the reproductive system (female) whereas the ureter belongs to the Excretory system.

(c) Ovum is the odd one here because Ovum is a part of the female reproductive system whereas the rest is a part of the male reproductive system.

(d) After birth is the odd one here because after birth is the discharge after birth takes place whereas the rest of the terms are processes and structures involved in reproduction. After-birth occurs after reproduction takes place.

(e) Follicle is the odd one here because all the other terms are related to childbirth and delivery whereas a maturing egg contained in a cellular sac is called the follicle.

Short Answer Type

Question 1

State whether the following statements are TRUE (T) or FALSE (F). Rewrite any two of the wrong statements by correcting only one word either at the beginning or at the end of the sentence.

  1. Fertilization occurs in vagina. (T/F)
  2. Uterus is also known as birth canal. (T/F)
  3. Nutrition and oxygen diffuse from the mother's blood into the foetus's blood through amnion. (T/F)

Answer

  1. False
    Corrected Sentence — Fertilization occurs in the fallopian tube.
  2. False
    Corrected Sentence — Vagina is also known as the birth canal.
  3. False
    Corrected Sentence — Nutrition and oxygen diffuse from the mother's blood into the foetus's blood through placenta.

Question 2

Complete the following table by writing the name of the structure or the function of the given structure:

StructureFunction
Corpus luteum1. ..........
..........2. Produces male gametes in mass
Leydig cells3. ..........
..........4. Increases the force in uterine contractions
Umbilical cord5. ..........
Fallopian tube6. ..........

Answer

StructureFunction
Corpus luteum1. Secretes progesterone & other hormones to prepare the uterine wall for the receival of the embryo.
Testes2. Produces male gametes in mass
Leydig cells3. Produce the male hormone testosterone
Oxytocin4. Increases the force in uterine contractions during child birth
Umbilical cord5. Connects placenta with foetus
Fallopian tube6. The site of fertilization for the sperm and ovum.

Question 3

Given below are the names of certain stages/substances related to reproduction and found in human body. Answer the questions related to them.

(a) Foetus

  • Where is it contained?
  • How does it differ from embryo?

(b) Hyaluronidase

  • Is it an enzyme or simply a protein?
  • What is its function?

(c) Morula

  • What is this stage?
  • Name the stage which comes next to it.

(d) Amniotic fluid

  • Where is it found?
  • What are its functions?

(e) Placenta

  • What are the two sources that form placenta?
  • Name any two main substances which pass from foetus to mother through placenta.
  • Name any two hormones it produces.

(f) Implantation

  • The development stage that undergoes this process.
  • The approximate time after fertilization, when it occurs.

Answer

(a) Foetus

  • It is contained in the uterus.
  • In foetus, limbs have appeared and resembles the humans unlike the embryo which is a growing or dividing zygote.

(b) Hyaluronidase

  • Enzyme
  • It is an enzyme secreted by the sperm that allows the sperm to penetrate the egg.

(c) Morula

  • It is the stage in the development of human embryo which consists of a spherical mass of cells.
  • Blastocyst

(d) Amniotic fluid

  • Between amnion and embryo
  • The functions of Amniotic fluid are:
    1. It protects the embryo from physical damage by jerks or mechanical shocks.
    2. Keeps an even pressure all around the embryo.
    3. Allows the foetus some restricted movement.
    4. Prevents sticking of the foetus to the amnion.

(e) Placenta

  • Placenta is formed by two sets of minute finger like processes called the villi. One set of villi is from the uterine wall and the other set is from the allantois.
  • Carbon dioxide and Urea pass from foetus to mother through placenta.
  • Two hormones produced by Placenta are Progesterone and Oestrogens.

(f) Implantation

  • Blastocyst
  • It occurs in about 5-7 days after fertilisation.

Question 4

Describe the functions of the following:

(a) Inguinal canal

(b) Testis

(c) Ovary

(d) Oviduct

Answer

(a) Inguinal canal — It allows the descent of testes along with their ducts, blood vessels and nerves, etc. The sperm duct from each Testis travels upwards into the abdomen passing through the Inguinal canal.

(b) Testis — Testis produce and store sperms.

(c) Ovary — Ovaries produce the egg cells, called the ova. The corpus luteum in the ovary secretes two hormones — Oestrogen and Progesterone.

(d) Oviduct — The two oviducts, also called Fallopian tubes carry the released ovum from the ovary to the uterus.

Question 5

Differentiate between:

(a) Semen and sperm

(b) Hymen and clitoris

(c) Uterus and vagina

(d) Efferent duct and sperm duct

(e) Follicle and corpus luteum

(f) Amnion and allantois

(g) Prostate gland and Cowper's gland

Answer

(a) Difference between semen and sperm —

SemenSperm
Semen is the mixture of sperms and secretions from seminal vesicles, prostrate and cowper's glands. It is a milky fluid.Sperms are human male gametes which are produced in the testes.

(b) Difference between hymen and clitoris —

HymenClitoris
Hymen is a thin membrane that partially covers the opening of vagina in young females.Clitoris is a small erectile structure located in the uppermost angle of vulva in front of the urethral opening.

c) Difference between uterus and vagina —

UterusVagina
Uterus is a hollow, pear shaped muscular organ located in the pelvic cavity.Vagina is the muscular tube extending from the cervix to the outside.

(d) Difference between efferent duct and sperm duct —

Efferent ductSperm duct
Efferent ducts join to form the epididymis.Sperm duct from each testis travels upward into the abdomen passing through an inguinal canal.

(e) Difference between follicle and corpus luteum —

FollicleCorpus luteum
The follicle is a cellular sac that contains the maturing egg.Corpus Lutuem is the remnant of the follicle after ovulation which is converted into a yellow mass.

(f) Difference between amnion and allantois —

AmnionAllantois
Amnion is the innermost thin membrane that develops around the embryo. Amniotic fluid fills the space between the amnion and the embryo.Allantois is another membrane that surrounds the developing embryo. It is an extension of the posterior wall of the yolk sac and lies between the amnion and the chorion.
Amnion protects the embryo from physical damage and keeps an even pressure all around the embryo.Allantois forms one of the villi of placenta and thus helps in the exchange of gases and handles waste from the developing embryo.

(g) Difference between Prostate gland and Cowper's gland —

Prostate glandCowper's glands
Prostate gland is a bilobed structure which surrounds the urethra close to its origin from the bladder.Cowper's glands are two small ovoid glands which open into the urethra just before it enters the penis.
Prostate gland pours an alkaline secretion into the semen as it passes through the urethra. It neutralises acid in female's vagina.The secretion from Cowper's glands serves as a lubricant.

Descriptive Type

Question 1

Define the following terms:

(a) Reproduction

(b) Hernia

(c) Ovulation

(d) Puberty

(e) Fertilization

(f) Hymen

Answer

(a) Reproduction — Reproduction is the process of formation of new individuals by sexual or asexual means, which can repeat the process in their own turn.

(b) Hernia — Hernia is an abnormal condition which is caused when the intestine due to the pressure in abdomen bulges into the scrotum through the inguinal canal.

(c) Ovulation — Ovulation is the rupture of the follicle releasing the egg .

(d) Puberty — Puberty is the period during which immature reproductive system in boys and girls matures and becomes capable of reproduction.

(e) Fertilization — The fusion of the male gamete (sperm) and the female gamete (ovum) to form a zygote is called fertilisation.

(f) Hymen — Hymen is a thin membrane which partially covers the opening of the vagina in young females.

Question 2

Distinguish between the following pairs:

(a) Spermatogenesis and oogenesis

(b) Implantation and gestation

(c) Pregnancy and parturition

(d) Placenta and umbilical cord

(e) Identical and fraternal twins

(f) Menarche and menopause

Answer

(a) Difference between spermatogenesis and oogenesis —

SpermatogenesisOogenesis
It is the process of production of sperms in seminiferous tubules of testes.Oogenesis is the process in which the ova - producing cells give rise to the mature ovum.

(b) Difference between implantation and gestation —

ImplantationGestation
The process of fixing of the blastocyst to the wall of the uterus/endometrium is termed implantation.The full term of the development of the embryo in the uterus is called gestation.

(c) Difference between pregnancy and parturition —

PregnancyParturition
It is the state of carrying a developing embryo or a foetus within the female body.It is the act of expelling the full term foetus from the mother's uterus at the end of gestation.

(d) Difference between placenta and umbilical cord —

PlacentaUmbilical cord
Placenta is the intimate connection established between the foetal membranes and uterine wall permitting diffusion of nourishment from the mother's blood to that of the growing foetus and disposal of wastes from the blood of the foetus to that of the mother.It is a cord containing blood vessels which connects the placenta with the foetus.

(e) Difference between identical and fraternal twins —

Identical twinsFraternal twins
Identical twins are produced by a single fertilised egg getting split into two parts during its early stages of cell division.Fraternal twins are produced by two different eggs which are released from the ovaries at a time and both got fertilised together.
Identical twins are either both boys or both girls.Fraternal twins may be either both boys or both girls or one boy and one girl.

(f) Difference between Menarche and Menopause —

MenarcheMenopause
It is the onset of menstruation in a young female at about the age of 13 years.It is the permanent stoppage of menstruation in females at about the age of 45 years.

Question 3

What is the significance of the testes being located in the scrotal sacs outside the abdomen? Can there be any abnormal situation regarding their location? If so, what is that and what is the harm caused due to it?

Answer

Testes are responsible for the production of male gametes i.e. sperms. The normal body temperature does not allow the maturation of the sperms. Being suspended outside the body cavity, the temperature in the scrotal sac is 2 to 3°C lower than that of the body which is the suitable temperature for the maturation of the sperms.
When it is too hot, the skin of the scrotum loosens so that the testes hang down away from the body. When it is too cold, the skin contracts in a folded manner and draws the testes closer to the body for warmth.
In an abnormal condition, in the embryonic stage, the testes do not descend into the scrotum. It can lead to sterility or incapability to produce sperms.

Question 4

Suppose a normal woman has never borne a child. How many mature eggs would she have produced in her lifetime? Your calculation should be based on two clues —

(a) Eggs are produced at the rate of 1 egg every 28 days (one menstrual cycle).

(b) A woman's total reproductive period is 13-45 years of age.

Answer

1 year = 12 months = 12 eggs (approx)

Total reproductive period = 45 - 13 = 32 years

Total eggs produced = 32 x 12 = 384 eggs approximately

She must have produced approximately 384 eggs in her lifetime.

Question 5

What are the secondary sexual characteristics in the human male and female respectively?

Answer

Secondary sexual characteristics in males:

  1. Deeper voice
  2. Hair growth on the face in the form of beard and moustache
  3. Stronger muscular built

Secondary sexual characteristics in females:

  1. High pitched voice
  2. Broad hips
  3. Development of breasts

Question 6

What are the accessory reproductive organs?

Answer

The accessory reproductive organs include all those structures, ducts and glands which help in the transfer and meeting of two kinds of sex cells leading to fertilization and in the growth and development of the egg up to the birth of the baby.

For example: Uterus in females, Penis in males.

Question 7

Differentiate between the primary and accessory reproductive organs.

Answer

Primary Reproductive OrgansAccessory Reproductive Organs
The primary reproductive organs do not help in the development of baby.The accessory organs help in the growth and development of egg up to the birth of baby.
The primary reproductive organs produce sex cells — the sperms and eggs.The accessory reproductive organs help in the transfer and meeting of two kinds of sex cells leading to fertilization.
Example: Testes in males and Ovaries in females.Example: Penis in males, Uterus, Vagina in female.

Question 8

Name and describe very briefly, the stages in the development of human embryo.

Answer

The different stages in the development of human embryo are described below:

Name and describe very briefly, the stages in the development of human embryo. The Reproductive System, Concise Biology Solutions ICSE Class 10.

Question 9

Is it correct to say that the testes produce testosterone? Discuss.

Answer

Testosterone is the male reproductive hormone produced by the interstitial cells or the Leydig cells. These cells are located in the testes. They serve as a packing tissue between the coils of the seminiferous tubules. Therefore, it can be said that the testes produce the male hormone testosterone.

Structured / Application / Skill Type

Question 1

Given below is a diagram of two systems together in the human body.

Given below is a diagram of two systems together in the human body. Name the systems. Name the parts numbered 1-10. Describe the functions of the parts 3, 4, 5 and 6. What will happen if the part 3 on both sides gets blocked? The Reproductive System, Concise Biology Solutions ICSE Class 10.

(a) Name the systems.

(b) Name the parts numbered 1-10.

(c) Describe the functions of the parts 3, 4, 5 and 6.

(d) What will happen if the part 3 on both sides gets blocked?

Answer

(a) Excretory system and Female Reproductive system.

(b) The parts numbered 1-10 are:

  • 1 → Kidney
  • 2 → Ureter
  • 3 → Fallopian Tube
  • 4 → Oviducal Funnel
  • 5 → Ovary
  • 6 → Uterus
  • 7 → Urinary Bladder
  • 8 → Cervix
  • 9 → Vagina
  • 10 → Vulva

(c) Functions of the parts are:

  • Fallopian Tube (part 3) — The fallopian tubes carry the ovum released from the ovary to the uterus.
  • Oviducal Funnel (part 4) — It is the funnel shaped distal end of the ovary which picks up the released ovum and pushes it further on its passage into the fallopian tube.
  • Ovary (part 5) — Ovary produces female gametes i.e. ova.
  • Uterus (part 6) — Uterus allows the growth and development of the embryo.

(d) If fallopian tube (part 3) on both sides gets blocked, the ovum released by the ovary will not be pushed into the oviduct and hence, there will be no possibility of fertilisation.

Question 2

The following diagram represents the vertical sectional view of the human female reproductive system.

The following diagram represents the vertical sectional view of the human female reproductive system. Label the parts indicated by the guidelines 1 to 8. How does the uterus prepare for the reception of zygote? What happens to the uterus, if fertilization fails to take place? The Reproductive System, Concise Biology Solutions ICSE Class 10.

(a) Label the parts indicated by the guidelines 1 to 8.

(b) How does the uterus prepare for the reception of zygote?

(c) What happens to the uterus, if fertilization fails to take place?

Answer

(a) The parts indicated by the guidelines 1 to 8 are:

  • 1 → Fallopian Tube
  • 2 → Funnel of Oviduct
  • 3 → Ureter
  • 4 → Vagina
  • 5 → Ovary
  • 6 → Uterus
  • 7 → Urinary Bladder
  • 8 → Urethra

(b) The lining of the uterus becomes thicker and develops more blood vessels under the influence of the increased amount of oestrogens produced by the ovary to prepare the uterus to receive the zygote and assist in the early implantation of the embryo and its subsequent development.

(c) If fertilization fails to take place, the thickened lining of the uterus (endometrium) restarts shedding on the 28th day of the menstrual cycle. Finally it is discharged out along with the unfertilised ovum as the menstrual flow through the cervix and the vagina.

Question 3

Given below is the schematic diagram of the sectional view of the human male reproductive system.

Given below is the schematic diagram of the sectional view of the human male reproductive system. Name the parts numbered 1-11. State the functions of the parts numbered 1, 2, 3, 5, 8 and 11. The Reproductive System, Concise Biology Solutions ICSE Class 10.

(a) Name the parts numbered 1-11.

(b) State the functions of the parts numbered 1, 2, 3, 5, 8 and 11.

Answer

(a) The parts numbered 1-11 are:

  • 1 → Seminal vesicle
  • 2 → Prostate gland
  • 3 → Bulbo-urethral glands
  • 4 → Epididymis
  • 5 → Testis
  • 6 → Scrotum
  • 7 → Urinary bladder
  • 8 → Sperm Duct (Vas deferens)
  • 9 → Erectile tissue
  • 10 → Penis
  • 11 → Urethra

(b) Functions of the parts are:

  • Seminal vesicle (Part 1) — They produce a secretion which serves as a medium for the transportation of the sperms.
  • Prostate gland (Part 2) — It produces an alkaline secretion which mixes with the semen and helps neutralise acid in female's vagina.
  • Bulbo-urethral glands (Part 3) — They produce a secretion which serves as a lubricant.
  • Testis (Part 5) — They produce the male gamete sperm and the male sex hormone testosterone.
  • Sperm Duct or Vas deferens (Part 8) — They carry the sperms from the epididymis to the urethra.
  • Urethra (Part 11) — It serves as an outlet for delivering the sperms into the vagina.

Question 4

The diagram below represents two reproductive cells A and B. Study the same and then answer the questions that follow:

The diagram below represents two reproductive cells A and B. Study the same and then answer the questions. Identify the reproductive cells A and B Name the specific part of the reproductive system where the above cells are produced. Where in the female reproductive system do these cells unite? Name the main hormone secreted by the (1) ovary (2) testes. Name an accessory gland found in the male reproductive system and state the function of its secretion. The Reproductive System, Concise Biology Solutions ICSE Class 10.

(a) Identify the reproductive cells A and B

(b) Name the specific part of the reproductive system where the above cells are produced.

(c) Where in the female reproductive system do these cells unite?

(d) Name the main hormone secreted by the (1) ovary (2) testes.

(e) Name an accessory gland found in the male reproductive system and state the function of its secretion.

Answer

(a) The reproductive cells A and B are:

  • A → Ovum
  • B → Sperm

(b) Parts of the reproductive system where the above cells are produced are:

  • Sperms are produced in the testis.
  • The ovum is produced in the ovary.

(c) The reproductive cells unite in the fallopian tubes of the female reproductive system.

(d) The main hormone secreted are:

  • Ovary → Oestrogen and progesterone
  • Testis →Testosterone

(e) Accessory glands found in the male reproductive system along with their functions are mentioned below:

  • Seminal vesicle — They produce a secretion which serves as a medium for the transportation of the sperms.
  • Prostate gland — It produces an alkaline secretion which mixes with the semen and helps neutralise acid in female's vagina.
  • Bulbo-urethral gland — They produce a secretion which serves as a lubricant.

Question 5

The diagram below is that of a developing human foetus in the womb. Study the same and answer the questions that follow:

The diagram  below is that of a developing human foetus in the womb. Study the same and answer the questions. Name the parts 1 to 5 indicated by guidelines. What term is given to the period of development of the foetus in the womb? How many days does the foetus take to be fully developed? Mention two functions of the parts labelled 2 other than its endocrine functions. Name any one hormone produced by the part labelled 2. The Reproductive System, Concise Biology Solutions ICSE Class 10.

(a) Name the parts '1' to '5' indicated by guidelines.

(b) What term is given to the period of development of the foetus in the womb?

(c) How many days does the foetus take to be fully developed?

(d) Mention two functions of the parts labelled '2' other than its endocrine functions.

(e) Name any one hormone produced by the part labelled '2'.

Answer

(a) The parts 1 to 5 are:

  • 1 → Umbilical cord
  • 2 → Placenta
  • 3 → Amnion
  • 4 → Mouth of uterus
  • 5 → Muscular wall of uterus

(b) Gestation

(c) 280 days

(d) Placenta provides the foetus with oxygen and nutrients. In addition, the placenta also removes carbon dioxide and waste products of the foetus.

(e) Progesterone

Question 6

Given below is a portion of the diagram to show the diagrammatic highly magnified view of a single human sperm. Complete the diagram to show its internal structure.

Given below is a portion of the diagram to show the diagrammatic highly magnified view of a single human sperm. Complete the diagram to show its internal structure. The Reproductive System, Concise Biology Solutions ICSE Class 10.

Answer

Completed diagram of a highly magnified view of a single human sperm is given below:

Given below is a portion of the diagram to show the diagrammatic highly magnified view of a single human sperm. Complete the diagram to show its internal structure. The Reproductive System, Concise Biology Solutions ICSE Class 10.

Question 7

Given below is the outline of the male reproductive system. Name the parts labelled 1 to 8. Also name the corresponding structure of part (4) in the female reproductive system.

Given below is the outline of the male reproductive system. Name the parts labelled 1 to 8. Also name the corresponding structure of part (4) in the female reproductive system. The Reproductive System, Concise Biology Solutions ICSE Class 10.

Answer

  • 1 → Urinary bladder
  • 2 → Ureter
  • 3 → Bulbo-urethral glands
  • 4 → Sperm duct/Vas deferens
  • 5 → Urethra
  • 6 → Testis
  • 7 → Scrotum
  • 8 → Epididymis

Fallopian tubes (oviducts) in females are analogous to sperm ducts in males. Sperm ducts carry sperms to the urethra, while fallopian tubes carry ova to the uterus.

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