CHAPTER 9 : REPRODUCTION & DEVELOPMENT · 2020. 7. 29. · BIOTWO SDS [Type here] SBI015 6 | KMPk...

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BIOLOGY TUTORIAL WORKSHEET

CHAPTER 9 : REPRODUCTION & DEVELOPMENT

SUBTOPIC : 9.1. Sexual Reproduction in Flowering Plants

LEARNING OUTCOMES:

a) State and define the terminologies involve in gamete formation in flowering plants:

i. Male gamete:

Microsporangium / pollen sac, microsporocyte / microspore mother cell, microspore, tetrad,

pollen grain / male gametophyte, generative cell, tube cell

ii. Female gamete:

Megasporangium, megasporocyte / megaspore mother cell, megaspore, female gametophyte /

embryo sac, antipodal cell, polar nuclei, egg cell, synergid cell

b) Explain the development of a pollen grain and the formation of male gamete

c) Explain the development of ovule, embryo sac and formation of female gamete

d) Explain double fertilization in the formation of seed

PART A : MULTIPLE CHOICE QUESTION

Diagram below shows a scheme of embryo sac development of a flowering plant.

1. What are represented by W, X and Y in the scheme above? (C1)

W X Y

A. Meiosis Mitosis Eight haploid nuclei

B. Meiosis Mitosis Four haploid nuclei

C. Mitosis Meiosis Eight haploid nuclei

D. Meiosis Meiosis Four haploid nuclei

One megaspore mother cell

4 cells

Megaspores

Antipodal cell / Synergid cell / Polar nuclei / Egg cell

W

X

Y


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2. In angiosperms, sperms are formed by (C2) A. meiosis in the anther. B. meiosis in the pollen grain.

C. mitosis in the anther. D. mitosis in the pollen tube.

3. In angiosperms, meiosis occurs in the _________________________, producing a spore that develops into a female gametophyte. (C1)

A. anther B. seed C. ovary D. fruit

4. Which of the following undergoes meiosis in the development of pollen grains? (C2)

A. Microspore

B. Megaspore

C. Megaspore mother cell

D. Microspore mother cell

5. Which statement about the megasporocyte is true? (C3)

A. It undergoes meiosis to produce three haploid cells.

B. It is a diploid cell located within an ovule.

C. It divides mitotically to form a male gametophyte.

D. It plays an important role in cross-pollination

6. Each pollen grain produces two cells, one of which may develop into: (C1)

A. a polar nucleus

B. a pollen tube

C. an anther

D. a stamen

7. The female plant structure on which a pollen grain will land is the: (C1)

A. style

B. pistil

C. stigma

D. anther


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8. How many nuclei are present in the embryo sac before fertilization? (C1) A. 2 C. 8 B. 4 D. 16

9. In the double fertilization below, which structures in the embryo sac will combine with the sperm cells to produce zygote and endosperm? (C2)

Zygote Endosperm

A. 1 2

B. 2 3

C. 2 4

D. 3 2

10. Following double fertilization, the ovule develops into ________ and the ovary develop

into ___________.(C1)

A. a cotyledon, an embryo B. an embryo, a seed C. a seed, a fruit D. a fruit, a seed

PART B: STRUCTURED QUESTIONS

1. FIGURE 1 shows longitudinal section of a flower and its reproductive parts during fertilization.

FIGURE 1

Embryo sac

1

2

3

4


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a) Name the male and female reproductive organs of the flower in FIGURE 1. (C1)

i) Male reproductive organ : ________________________________________

ii) Female reproductive organ : ________________________________________

[2 marks]

b) Label structures A, B, C and D in FIGURE 1. (C1)

A : _______________________________

B : _______________________________

C : _______________________________

D : _______________________________

[4 marks]

c) What is the structure that develops just after the pollen grains have landed on A? (C2)

__________________________________________________________________

[1 mark]

2. Name the process and structures involved in the development of pollen grain and formation of male

gametes in FIGURE 2. (C1)

[5 marks]

1.

5.

2.

3.

4.

FIGURE 2


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3. Label the structures involved in the development of ovule, embryo sac and formation of female gamete in

FIGURE 3. (C1)

[5 marks]

4. a) Name the structures involved in sexual reproduction of flowering plants in FIGURE 4 and FIGURE 5.

b) Based on FIGURE 4, name the process that takes place when the pollen tube penetrates the ovule through

the micropyle.

__________________________________________________________________

[1 mark]

2.

3.

5.

1.

4.

FIGURE 3

FIGURE 4 FIGURE 5

1.

3.

2.

4.

1.

2.

3.


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c) Describe how the process mentioned in 1 (b) occurs in a flower.

___________________________________________________________________________________

___________________________________________________________________________________

___________________________________________________________________________________

[2 marks]

5. Fill in the blanks for steps in double fertilization in plant on FIGURE 6.(C1).

PART C : ESSAY QUESTIONS

1. Explain the development of pollen grains and the formation of male gametes. (C3) [10 marks]

2. Rewrite the double fertilization process in flowering plants based on FIGURE 6 above.(C3) [8 marks]

Pollen grain lands on a _____________ and thorny stigma

It absorbs water and _____________________

Producing _______________that grows down the _______

towards the _______________

Generative nucleus/cell divide by ____________ to produce

two ________________________

Chemical signal from _________________ will attract

pollen tube grows towards the micropyle

2 male gametes discharged enter the ______________ and

fuse with the nuclei

One male gamete fertilizes the __________ to form the

_____________(2n). The other male gamete combine with

two __________________ to form an ______________(3n)

in the central cell.

FIGURE 6

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SUBTOPIC : 9.2. Human Reproductive System

LEARNING OUTCOMES:

a) Overview male reproductive organ (testes) and the structure of spermatozoa

b) Explain the structure of spermatozoa

c) Explain the role of hormones in spermatogenesis: Gonadotropin-Releasing Hormone (GnRH),

Luteinizing Hormone (LH), Follicle stimulating Hormone (FSH) and Testosterone.

d) Explain the stages in spermatogenesis and its hormonal control.

e) Overview female reproductive organ (ovary) and the structure of secondary oocyte.

f) Explain the structure of secondary oocyte.

g) Explain the role of hormones in female reproductive cycle: Gonadotropin-Releasing Hormone (GnRH),

Luteinizing Hormone (LH), Follicle stimulating Hormone (FSH), Estrogen and Progesterone.

h) Explain the stages in oogenesis.

i) Explain female reproductive cycle and its hormonal control:

i. Ovarian cycle

ii. Uterine / menstrual cycle

PART A : OBJECTIVE QUESTIONS

1. In spermatogenesis, the primordial germ cells undergo mitotic division and differentiation to form (C1) A. spermatid

B. sperms

C. diploid spermatogonia

D. haploid spermatogonia

2. The following are stages in spermatogenesis. (C2) P: Spermatogonium.

Q: Primary spermatocyte.

R: Secondary spermatocyte.

S: Spermatid.

Which of the following stages involve haploid cells?

A. P and Q. B. P and S. C. R and S. D. Q and R

3. Where are human sperms produced? (C1) A. Prostate gland B. Vas deferens C. The seminiferous tubules of the testes D. Epididymis

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4. Which of the following produce testosterone? (C1) A. Sertoli cells B. Hypothalamus C. Leydig cells D. Anterior pituitary

5. In oogenesis, the first meiotic division completes during the development of (C1) A. primordial germ cells to oogonium. B. oogonium to primary oocytes. C. primary oocytes to secondary oocytes. D. secondary oocyte to ovum.

6. Arrange the following stages of oogenesis in sequential order (C1) 1. Secondary oocyte 2. Oogonium 3. Ovum 4. Primary oocyte

A. 4,1,2,3 B. 4,3,2,1 C. 3,2,4,1 D. 2,4,1,3

7. In vertebrate animals, spermatogenesis and oogenesis differ in that (C2) A. Oogenesis begins at the onset of sexual maturity. B. Oogenesis produces haploid cells whereas spermatogenesis produces only one functional sperm. C. Oogenesis produces one functional ovum whereas spermatogenesis produces four functional

spermatozoa.

D. Spermatogenesis begins before birth.

8. In the female _____________ stimulates follicle maturation. (C1) A. GnRH B. LH C. FSH D. Estrogen

9. One function of the developing follicle is to: (C1) A. Stimulate ovulation B. Secrete progesterone C. Secrete estrogen D. Secrete prolactin

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10. The graph below shows the level of hormones in a menstrual cycle

Which of the following shows the menstrual period ? (C1)

A. I only B. II to III C. IV to V D. V to I

11. What are three phases of the ovarian cycle? (C1) A. Menstrual, ovulation and luteal B. Follicular, luteal and secretory C. Menstrual, proliferative and secretory D. Follicular, ovulation and luteal

12. Diagram below shows the changes in the thickness of the endometrium in a menstrual cycle. (C2)

At which stage will implantation take place if fertilization occurs?

I II III IV V

Thickness of

endometrium

A B C D

28 Time

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13. Ovulation usually occurs on or about day ____ of a 28-day ovarian cycle? (C1) A. 1 B. 7 C. 14 D. 21

14. Peaks of LH and FSH production occur during (C1) A. The flow phase of menstrual (uterine) cycle. B. The beginning of the follicular phase of the ovarian cycle. C. The period just before ovulation. D. The end of the luteal phase of the ovarian cycle.

15. After ovulation, high levels of ______________ inhibit _____________ secretion. (C1) A. FSH and LH; estrogen and progesterone B. Estrogen and progesterone; FSH and LH C. HCG; estrogen and progesterone D. Estrogen; FSH

16. The function of corpus luteum is to: (C1) A. Nourish and protect the egg cell B. Produce prolactin in the mammary gland C. Produce progesterone and estrogen D. Convert into a hormone-producing follicle after ovulation

17. Which of the followings best describes the menstrual cycle? (C2) A. It begins with the follicular phase. B. It continues from puberty until death. C. The cycle length is 26 days. D. It refers specially to changes that occurs in the endometrium of the uterus.

18. The secretory phase of the menstrual cycle (C2) A. Is associated with dropping levels of estrogen and progesterone. B. Starts with the endometrium begins to degenerate. C. Corresponds with the luteal phase of the ovarian cycle. D. Corresponds with the follicular phase of the ovarian cycle.

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PART B :STRUCTURED QUESTIONS

1. FIGURE 1 shows the stages of spermatogenesis.

a) . Identify A, B and C. (C1)

A: C:

B:

[3 marks]

b) State the ploidy number of cell B and cell C. (C2) B:

C:

[2 marks]

c) Name the hormone produced by Cell X that stimulates spermatogenesis. (C1)

[1 mark]

d) Cell Y is important in the development of D into E. Name Cell Y and its function. (C2)

Cell Y:

Function:

[2 marks]

FIGURE 1

Cell X

Capillary

Basement

membrane

Fibrous connective

tissue

A

B

C

Cell Y

Nucleus of

Cell Y

D

E

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e) Why do cell X and cell Y important during spermatogenesis in terms of negative feedback mechanism? (C3)

[2 marks]

2. Fill in the blanks with the correct answers based on FIGURE 2. (C1)

FIGURE 2

……………………………cells (2n) divide by mitosis to form spermatogonia (2n)

Some of spermatogonium (2n) remains at the

basement membrane as precursor stem cells

and another spermatogonium (2n)

differentiate/increase in size forming primary

spermatocytes (2n).

Primary spermatocytes (2n)

undergo ……………… forming two

secondary spermatocytes (n).

Secondary spermatocytes (n)

undergo ……………... forming four

spermatids (n).

Spermatids (n) are non-motile and become

embedded in ……………………..to get

the …………………

Spermatids (n) undergo ………………….. to

form spermatozoa/ sperm cell (n).

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3. Label the structures of spermatozoa in FIGURE 3. (C1)

4, Name the hormones involved in spermatogenesis in FIGURE 4. (C1)

4.

2.

3. 1.

5.

6.

7.

1.

5.

2.

4.

3.

FIGURE 4

FIGURE 3

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5. Name the process involved in oogenesis in FIGURE 5 below. (C1)

FIGURE 5

1.

2.

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6. Fill in the blanks with the correct answers based on FIGURE 6. (C1)

…………………………. cells (2n) divide repeatedly by mitosis forming oogonia (2n)

Oogonia (2n) divide by mitosis to form

primary oocytes (2n)

Primary oocytes (2n) undergo meiosis I but

arrested at …………………

At puberty, follicle-stimulating hormone

(FSH) stimulates the growth and

development of follicles. Only one follicle

fully matures each month, with its primary

oocyte completing meiosis I forming

secondary oocyte (n)

and ………………………….. (n)

Secondary oocyte (n) undergoes meiosis II

but arrested at ………………

The secondary oocyte (n) is released

during …………………….

Meiosis II complete to form ovum

and …………………………….. when

sperm (n) penetrates the secondary oocyte

(n) and fertilization occurs

The entry of sperm triggers completion of

meiosis II in ……………………….

……………………………. (n) will eventually degenerates.

FIGURE 6

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7. Label the parts of secondary oocyte in FIGURE 7. (C1)

8. Label the phases involved in ovarian cycle in FIGURE 8. (C1)

FIGURE 7

a)

b)

c)

d)

e)

f)

FIGURE 8

2. 1.

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9. Name the phases involved in uterine cycle in FIGURE 9. (C1)

10. Arrange the following statements in the correct order for ovarian cycle in FIGURE 10 below. (C3)

Secretion of estrogen increases as the follicle grows bigger and stimulates the secretion

of FSH and LH by the positive feedback mechanism.

After ovulation, LH stimulates the development of corpus luteum from the empty

Graafian follicle.

LH indirectly stimulates the secretion of estrogen by the developing/Graafian follicle.

Surge of LH stimulates the maturation of follicle and ovulation.

GnRH stimulates anterior pituitary gland to secrete follicle-stimulating hormone (FSH)

and luteinizing hormone (LH).

LH also stimulates corpus luteum to secrete progesterone and estrogen

FSH stimulates the development of follicles in the ovary from primary follicle to

become Graafian follicle.

As the level of progesterone and estrogen increase, they exert negative feedback on the

hypothalamus and anterior pituitary gland to inhibit the secretion of LH and FSH.

Without maintenance from LH, the corpus luteum disintegrates and the levels of

progesterone and estrogen decrease.

Hypothalamus starts to secretes Gonadotropin-releasing hormone (GnRH) to stimulate

the growth of new follicles in the ovary.

As the estrogen level rise, it causes the decrease of FSH by the negative feedback

mechanism to ensure only one follicle to be developed at one time

Hypothalamus free from negative feedback and the next cycle begins.

3. 2. 1.

FIGURE 9

FIGURE 10

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1. Rewrite the development of spermatozoa in spermatogenesis based on FIGURE 2 above. (C3)

[10 marks]

2. Discuss the roles of hormones and negative feedback mechanism in spermatogenesis by referring to

FIGURE 4 above. (C3)

[10 marks]

3. Rewrite the development of ovum in oogenesis based on FIGURE 6 above. (C3)

[10 marks]

4. Compare and contrast the spermatogenesis and oogenesis. (C2)

[10 marks]

5. Rewrite the ovarian cycle based on FIGURE 10 above. (C3)

[10 marks]

6. Describe the uterine cycle in female based on figure below. (C3)

[10 marks]

Menstrual flow phase

Proliferative phase

Secretory phase

Estrogen and

progesteron Corpus

luteum

Endometrium

wall

Estrogen Endometrium

wall

Estrogen and

progesteron Corpus

luteum

Endometrium

wall

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SUBTOPIC : 9.3. Fertilization and foetal development

LEARNING OUTCOMES:

a) Explain the stages that lead to fertilization:

i. Capacitation

ii. Acrosomal reaction

iii. Fusion of sperm head membrane and oocyte

iv. Cortical reaction

b) Define embryogenesis.

c) State developmental stages from zygote to the formation of morula, blastocyst and gastrula through

cleavage.

d) Define organogenesis.

e) State the organ formed from each germ layers during organogenesis.


1. Before a sperm can complete in fertilization, it must undergo a maturation process in the female reproductive tract known as: (C1)

A. the acrosomal reaction. B. the cortical reaction. C. spermatogenesis. D. capacitation.

2. Which of the following statement about capacitation is true? (C1) A. The increase in estrogen level to stimulate the formation of oxytocin receptor. B. The production of prostaglandin that contracts endometrium wall. C. The formation of fertilization membrane by zona pellucida. D. The enhancement of sperm function in the oviduct.

3. During the acrosomal reaction, the acrosome: (C1) A. Detaches, allowing the sperm to penetrate the egg. B. Releases enzymes that digest the outer layer of the egg. C. Secretes calcium ions, which cause the sperm to fuse with the egg. D. Releases inhibin, which causes the sperm to bind to the egg.

4. The cortical reaction of eggs functions directly in the (C2) A. formation of a fertilization envelope. B. production of a fast block to polyspermy. C. release of hydrolytic enzymes from the sperm cell. D. generation of an electrical impulse by the egg cell.

5. Degeneration of the corpus luteum and spontaneous abortion can occur due to lack of: (C2) A. Estrogen B. Progesterone C. LH D. hCG

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6. Which of the following is the correct sequence through which early development proceeds? (C1)

A. Morula cleavage gastrula blastula

B. Cleavage blastula morula gastrula

C. Cleavage blastula gastrula morula

D. Cleavage morula blastula gastrula

7. Each cell in an early embryo is called a (C1)

A. blastopore

B. blastocoel

C. blastomere

D. archenteron

8. What is the stage of human embryo during implantation? (C1)

A. Blastocyst

B. Gastrula

C. Morula

D. Neurula

9. Which of the following initiates implantation by secreting enzymes that breakdown the endometrium? (C1)

A. Inner cell mass

B. Endoderm

C. Chorion

D. Trophoblast

10. Which of the following consists of a hollow ball of cells? (C1)

A. Gastrula

B. Morula

C. Blastula

D. Blastocoels

11. The process that involves the movement of the cells and results in the establishment of three germ tissue

layers is called: (C1)

A. determination

B. cleavage

C. gastrulation

D. neurulation

12. After gastrulation, the outer-to-inner sequence of tissue layers in a vertebrate is (C1)

A. endoderm, ectoderm, mesoderm

B. mesoderm, endoderm, ectoderm

C. ectoderm, mesoderm, endoderm

D. ectoderm, endoderm, mesoderm

13. Embryonic endoderm gives rise to _______________ while mesoderm to _____________. (C1)

A. muscle, epidermis

B. lining of the digestive tract, excretory system

C. nervous system, lining of the digestive tract

D. skin, pituitary gland

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14. The first system to develop in the vertebrate embryo is the: (C2)

A. circulatory system

B. digestive system

C. excretory system

D. nervous system

15. Which of the following is mismatched? (C1)

A. mesoderm- notochord

B. endoderm- lining of respiratory system

C. ectoderm- liver

D. mesoderm-muscle

PART B : STRUCTURED QUESTIONS

1. Name the stages that lead to fertilization of ovum by sperm in FIGURE 1. (C1)

1.

2. 3.

4.

FIGURE 1

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2. Name the stages of fertilization in FIGURE 2. (C1)

Stages Description

Final maturation of the spermatozoa.

Remove the glycoprotein layer – expose the sperm’s receptor

Sperm’s mortality increase

Sperm’s head bind with specific receptor in on zona pellucida

Hydrolytic enzyme discharge to hydrolyze zona pellucida

Sperm’s head reach the plasma membrane of secondary oocyte,binds

and fuses with the egg plasma membrane.

complete meiosis ll

Cortical granule release enzyme to zona pellucida by exocytosis

Zona pellucida harden

Prevent polyspermy

FIGURE 2

3. Label the stage and process involved in embryogenesis in FIGURE 3. (C1)

2. 3.

1.

4.

FIGURE 3

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4. Label the parts of embryo in FIGURE 4 and FIGURE 5. (C1)

5. FIGURE 6 shows the process of ovulation, fertilization and implantation in human.

a) Name the structures labelled M, N, P and Q. (C1)

M:_______________________

N:_______________________

P:_______________________

Q:_______________________ [4 marks]

1. 2.

3.

FIGURE 5 FIGURE 4

P

O Q

Uterus wall N

Process Y Early stage of

implantation

Ovary

M

FIGURE 6

1.

3.

2.

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b) Name process Y. State the hormone which triggers this process. (C1)

_________________________________________________________________________

[2 marks]

c) Name the hormone which is produced by M and their function for Q implantation. (C1)

_______________________________________________________________________

_______________________________________________________________________

[2 marks]

d) Briefly explain what happen to N, immediately after fertilization process. (C1)

__________________________________________________________________________

__________________________________________________________________________

[2 marks]

6. Match the correct pairs of development of germ layers to the formation of organ during organogenesis in FIGURE 7. (C1)

Germ layers Develop into

Ectoderm skeletal, muscular, reproductive & excretory systems, skin dermis,

‘notochord’.

Endoderm skin epidermis, mouth & rectum lining, nervous system.

Mesoderm lining & glands in digestive tract & respiratory system, lining of

urinary bladder.

FIGURE 7


1. Describe the events that occur during human fertilization until the stage when the sperm enters the cytoplasm of

the egg. (C2)

[10 marks]

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SUBTOPIC : 9.4. Roles of hormones during pregnancy and parturition

LEARNING OUTCOMES:

a) Explain the roles of hormones during pregnancy

i. Progesterone

ii. Estrogen

iii. Human chorionic gonadotropin (hCG)

b) Explain the roles of hormones during parturition / birth process.

i. Progesterone

ii. Estrogen

iii. Oxytocin

iv. Prostaglandin


1. Which of the following hormones is incorrectly paired with its action? (C1) A. Oxytocin – stimulate the contraction of the uterus

B. Estrogen – stimulate the thickening of the endometrium lining

C. Human chorionic gonadotropin - maintain secretions from the corpus luteum

D. Progesterone – stimulates maturation of follicle

2. What is the factor that caused miscarriage in pregnant woman? (C2) A. Low level of luteinizing hormone B. Low level of progesterone C. Low production of estrogen D. Insufficient of oxytocin

3. During human pregnancy, rudiments of all organs develop (C2) A. in the first trimester B. in the second trimester C. in the third trimester D. while the embryo is in the oviduct

4. Fetus is very active Fetal movement may be visible through abdominal wall

Level of hCG hormone decline

The corpus luteum deteriorate

Placenta secretes progesterone

The statements above show that the fetus is in _____________ stage. (C2)

A. first trimester B. second trimester C. third trimester D. final

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5. Which of the following hormones inhibits contraction of the uterus? (C1) A. Cortisol B. Oxytocin C. Prostaglandins D. Progesterone

6. What would happen if a woman in the later stages of pregnancy were given a combination of estrogen and oxytocin? (C2)

A. Oxytocin receptors would develop on uterine smooth muscle B. Prostaglandins would be secreted from the placenta C. Contractions of uterine muscles would begin D. All of the above are correct

7. During the second stage of labor: (C1) A. the cervix begins to dilate B. the cervix relaxes C. the fetus is delivered D. the uterus begins to contract

8. Afterbirth refers collectively to: (C1) A. the fetus and the placenta B. the fetus and the surrounding fetal membranes C. the fetus and the umbilical cord D. the placenta and the fetal membranes

9. Colostrum is: (C1) A. the hormone that stimulates lactation B. the hormone that stimulates the ejection of milk into the breast C. the earliest protein fluid produced by the mammary gland D. the hormone that stimulates the mammary gland to produce milk

10. Which of these is not a correct statement about human reproduction? (C2) A. Early division of the embryo occurs in the oviduct B. Implantation occurs about 24 hours after fertilization C. By eighth week, organogenesis is complete and the embryo is referred to as a fetus D. Lactation is the production and release of milk from the mammary glands

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PART B : STRUCTURED QUESTIONS

1. Name the hormones involved during parturition in FIGURE 1. (C1)

2. Complete FIGURE 2 below for hormones during pregnancy and lactation. (C1)

Hormones Produced by Functions

1. Corpus luteum : from

fertilization until placenta

is formed

2. Placenta : after

placenta is fully

developed.

- Maintains & thickened the endometrium.

- Maintains the placenta.

- Inhibit uterus contraction.

- Stimulates growth of mammary glands & ducts.

- Inhibit lactation until after the birth

- Strengthens the mucus covering the cervix to prevent

infection.

- Strengthens the pelvic walls in preparation for labor.

1. Corpus luteum : from

fertilization until placenta

is formed

2. Placenta : after

placenta is developed.

-Stimulate & regulate the production of progesterone

by placenta.

- Maintains the endometrium during pregnancy

- Maintain the fetus organ’s development.

- Facilitate the development of female sexual

characteristics by protecting female fetus from the

effects of androgens in the mother's system.

- Regulates bone density in a fetus

- Promotes blood flow within the uterus

- Stimulates the growth of mammary glands and ducts.

FIGURE 1

1. 2.

3.

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Produced by the embryo

after implantation.

-Stimulates the corpus luteum to continue producing

progesterone and estrogen until placenta is fully

developed.

Produced by anterior

pituitary

-Stimulates milk production in mammary glands.

Produced by mother’s

posterior pituitary.

- Control the release of milk by mammary glands.

- Stimulated by the sucking of the baby on the

mother’s breast which stimulates the contraction of

smooth muscle around the mammary glands.

FIGURE 2


1. Explain the role of hormones during pregnancy. (C2) [10 marks]

2. Describe the role of hormones during parturition. (C2) [10 marks]

CHAPTER 9 : REPRODUCTION & DEVELOPMENT · 2020. 7. 29. · BIOTWO SDS [Type here] SBI015 6 | KMPk...

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