Integrated Science M3 Fertilization, Pregnancy and birth

NEXTNEXT

Integrated Science,Integrated Science,Module 3Module 3 Unit 7 Unit 7 Lesson 9, Lesson 9,

Part A And B Part A And B

This Power point slide presentation supports M3U7L9. It is divided into two parts as follows: Part A – Fertilization and Implantation Part B – Pregnancy and Birth

FERTILIZATION AND IMPLANTATIONFERTILIZATION AND IMPLANTATION

Module 3Module 3 Unit 7 Unit 7 Lesson 9, Part A Lesson 9, Part A Integrated ScienceIntegrated Science

BEGIN


OBJECTIVESOBJECTIVES

How is an egg Fertilized?


ImplantationImplantation

QUICK QUIZQUICK QUIZ

INTRODUCTIONINTRODUCTION Get your mind thinking by doing this QUICK QUIZ from

http://www.neok12.com/vocabulary/Reproductive-System-02.htm You will be using these names of the female

reproductive system throughout this slide presentation so it’s good to make sure you remember each one.

Click, watch and recall the passage of the egg from ovulation at http://www.mayoclinic.com/health/ovulation/MM00108

4

http://www.neok12.com/vocabulary/Reproductive-System-02.htm

http://www.mayoclinic.com/health/ovulation/MM00108







INTRODUCTIONINTRODUCTION When you complete this slide presentation, you should be able to: define fertilization and implantation.distinguish between a zygote, an embryo and a foetus.recognize the importance of fertilization in sexual reproduction.

5







INTRODUCTIONINTRODUCTION Before fertilization, there is normally sexual arousal and copulation, during which, the penis becomes erect and this erection enables its insertion into the vagina.

6

Sperm swim up through the cervix and into the uterus; 30 minutes later, sperm enter the oviducts. In the upper third of one oviduct, sperm meet and encircle the egg.

Stimulation from rhythmic movements during sexual intercourse causes ejaculation. This releases millions of sperm into the vagina.







INTRODUCTIONINTRODUCTION One sperm fuses with the egg surface. The egg completes the second division of meiosis.

Both haploid egg and sperm nuclei fuse. Entry of one sperm prevents others entering, because changes occur in the membrane that keep out any other sperm.

A zygote is formed from fertilization. The sex of the person is determined from this early stage, depending on whether the sperm that fertilized the egg had an X or a Y chromosome in its set of 23 chromosomes.

Click and watch the video of fertilization >(

http://www.bbc.co.uk/schools/gcsebitesize/science/edexcel_pre_2011/genes/reproductionandcloningrev1.shtml Make sure you can define fertilization correctly.

7

http://www.bbc.co.uk/schools/gcsebitesize/science/edexcel_pre_2011/genes/reproductionandcloningrev1.shtml







INTRODUCTIONINTRODUCTION Fertilization serves the following purposes:1. It enables transmission of genes from both

parents to a new organism, thus increasing the chances of survival of the species in times of adversity.

2. It enables restoration of the diploid number of chromosomes that had been reduced during meiosis when gametes were being formed. It initiates the development of offspring

Reference source:http://bookmark.sunfinedata.com/www-content/book/ebooks/online%20biology/BioBookREPROD.html

8

http://bookmark.sunfinedata.com/www-content/book/ebooks/online%20biology/BioBookREPROD.html







INTRODUCTIONINTRODUCTION Aren’t twins cute? So, how do we get twins? 1. Sometimes more that one egg matures and ovulates at the

same time and both/all may be fertilized separately. This can result in fraternal twins or in multiples who can be either same sex or different-sex children. These are non-identical twins or multiples.

2. When the zygote first divides, the halves can separate and each develops into an embryo. This results in identical, same sex twins. Why are they identical and same sex?

9

Feedback: Both persons are formed from a single fertilized egg which becomes the 1-cell zygote. It is the zygote that divides twins!







INTRODUCTIONINTRODUCTION

10

This zygote divides by mitosis and grows into a hollow ball of cells, then into an embryo. It is called an embryo up to about six weeks after conception

This zygote divides by mitosis and grows into a hollow ball of cells, then into an embryo. It is called an embryo up to about six weeks after conception

As it divides, the ball of cells moves down the oviduct/Fallopian tube into the uterus.

As it divides, the ball of cells moves down the oviduct/Fallopian tube into the uterus.

The embryo becomes embedded in the thick, soft layer of tissues that is the endometrial layer of the uterus wall.

The embryo becomes embedded in the thick, soft layer of tissues that is the endometrial layer of the uterus wall.

THIS IS IMPLANTATION. THIS IS IMPLANTATION. THIS IS IMPLANTATION. THIS IS IMPLANTATION.

1111

2222

3333

4444







INTRODUCTIONINTRODUCTION 1. What is the chromosome number of the zygote?

11

NEXT QUESTIONNEXT QUESTION

Feedback: Yes! The zygote is diploid.







INTRODUCTIONINTRODUCTION 2. Do you remember what caused thickening of the endometrial wall with blood?

12


Feedback: The endometrial wall is thickened with blood due to the action of the hormone oestrogen secreted as the follicle developed. Another hormone, progesterone from the corpus luteum, is also responsible.







INTRODUCTIONINTRODUCTION 3. What is the chromosome number of each embryonic body/somatic cell in humans?

13

Feedback: Each has the diploid number or 23 pairs.








INTRODUCTIONINTRODUCTION Read each statement. Click TT if the statement is True and F if False. 1.Fertilization occurs in the upper part of the Fallopian tube.

2.A fertilized egg is called an embryo.

3.The wall of the uterus thickens before fertilization to accommodate an embryo.

4.Normally, only 1 sperm can fertilize an egg. 14

14 MORE FEEDBACKMORE FEEDBACKMORE FEEDBACKMORE FEEDBACK

TT FF

TT FF

TT FF

FFTT







INTRODUCTIONINTRODUCTION 1. Fertilization occurs in the upper part of the Fallopian tube. True - Fertilization occurs in the upper 1/3 of Fallopian tube

2. A fertilized egg is called an embryo. False - A fertilized egg is called a zygote – NOT an embryo.

3. The wall of the uterus thickens before fertilization to accommodate an embryo. True – Yes, every month, to prepare for a possible fertilization, the inner layer or endometrium of the uterus thickens and develops additional blood supply.

4. Normally, only 1 sperm can fertilize an egg. True -Only 1 sperm can fertilize an egg

1515 NEXT QUESTIONNEXT QUESTIONNEXT QUESTIONNEXT QUESTION







INTRODUCTIONINTRODUCTION Read each statement. Click TT if the statement is True and F if False. 5.A zygote normally has the haploid set of chromosomes. 6.Identical twins result if two sperms fertilize the same egg. 7.After an egg is ovulated, it is implanted then passed out in menstruation if it is not fertilized. 8.It is the chromosome from the sperm that determines the sex of the human offspring.

1616 MORE FEEDBACKMORE FEEDBACKMORE FEEDBACKMORE FEEDBACK

TT FF

FFTT

FFTT

FFTT







INTRODUCTIONINTRODUCTION 5. A zygote normally has the haploid set of chromosomes. False – a sperm and an egg each have the haploid number of chromosomes because they are formed during meiosis or reduction division, so when they fuse the diploid number of chromosomes is restored in the zygote.

6. Identical twins result if two sperms fertilize the same egg. False - Some kind of mutation would most likely result if, by chance, two sperms were able to fertilize the same egg. Normally, a membrane forms immediately around the egg once a sperm nucleus enters it for fertilization, and this membrane prevents the entry of other sperms, so this is very unlikely to happen.

7. After an egg is ovulated, it is implanted then passed out in menstruation if it is not fertilized. False – The usual sequence is: Ovulation Fertilization Implantation OR, it could be: Ovulation No Fertilization Menstruation.

8. It is the chromosome from the sperm that determines the sex of the human offspring. True – A male has XY chromosomes. Each sperm contains either an X chromosome or a Y chromosome. Every egg contains an X chromosome. So, to get a male, the Y chromosome sperm must be the one to fertilize the X-chromosome egg to give the XY zygote male human.

1717 NEXT QUESTIONNEXT QUESTIONNEXT QUESTIONNEXT QUESTION

Integrated Science,Integrated Science, Module 3 Module 3 Unit 7 Unit 7 Lesson 9 , Part B Lesson 9 , Part B

PREGNANCY AND BIRTHPREGNANCY AND BIRTHPREGNANCY AND BIRTHPREGNANCY AND BIRTH

Module 3Module 3 Unit 7 Unit 7 Lesson 9, Part B Lesson 9, Part B Integrated ScienceIntegrated Science

BEGINBEGIN

PREGNANCY AND BIRTHPREGNANCY AND BIRTH



Changes during Pregnancy


PregnancyPregnancy

After birthAfter birth

BirthBirth


INTRODUCTION1. Click and watch this video from

http://www.youtube.com/watch?v=xgif4TR-qqQ&feature=related

2. Did you hear some of the symptoms that this woman is experiencing? Her period is already six days late, she’s feeling “nauseated, tired and mean”? From all of these, she suspects that she is pregnant.

3. If her test is positive, what changes can she expect to occur in her body? And, when it’s time, will she go through labour all right? Will she have a normal healthy baby? Let’s see what happens.

19






PregnancyPregnancy


BirthBirth


OBJECTIVES

When you finish this slide presentation, you should be able to:•describe how the female’s body changes during pregnancy and birth. •outline the development of a foetus up to birth.•state the functions of the placenta.•list the stages of birth

20






PregnancyPregnancy


BirthBirth


1. Pregnancy• What is pregnancy? Many doctors will say that

pregnancy starts at conception when sperm fertilizes egg. Some say it starts at implantation of the foetus.

• The period of gestation or pregnancy is the term used to describe the typically 40 weeks when a woman actually has one foetus, or more, growing and developing inside of her uterus. It ends with labour and childbirth.

• Ovulation, fertilization and implantation are all a part of the preliminary pregnancy process! Click link below and watch from 0.18s:

http://www.youtube.com/watch?feature=fvwp&v=HU5F30JS8U4&NR=1

21

http://www.youtube.com/watch?feature=fvwp&v=HU5F30JS8U4&NR=1






PregnancyPregnancy


BirthBirth


1. Pregnancy – Signs of Pregnancy

I know you have been associated with pregnant persons.

1.Can you think of some of the signs that show that a woman is pregnant?

Perhaps you thought of swelling of feet, nose and face, looking fat… abdomen getting larger. What else happens?

2.Watch the video at the link -http://www.youtube.com/watch?v=3njWm2skG2U&feature=relmfu

22






PregnancyPregnancy


BirthBirth


1. PregnancyFeedback to Question 1.1

Some of the signs that show that a woman is pregnant?

2323

Nausea and vomiting may occur, due to the

increase in progesterone levels. They are among the first changes that occur in pregnancy.

The periods cease until after the baby

is born.

There may be lethargy or tiredness.

Breasts feel tender and they and

abdomen begin to enlarge.

There may be increased irritability,

mood swings and food cravings or food

rejections.






PregnancyPregnancy


BirthBirth


1. Pregnancy - The TrimestersThe Trimesters• Pregnancy is divided into stages, each a called trimester.• “The first trimester is officially from the first day of the last

menstrual period of the mother till the end of the 12th week of clinical pregnancy. The second trimester is from the 13th till the 28th week; and the 3rd trimester lasts from the 29th week till the birth of the baby. “

24






PregnancyPregnancy


BirthBirth


1. Pregnancy – The TrimestersThe Trimesters1st Trimester = 1st 12 weeks1st Trimester = 1st 12 weeks• The heart develops first.• The neural tube develops.• All body systems appear by Week 8 – Now a Fetus2nd Trimester = up to 24 weeks2nd Trimester = up to 24 weeks• Most growth of the foetus occurs during this trimester.• The foetus starts to look more like a baby, less like tadpole.• If born at this stage, a premature baby could survive.3rd Trimester = Up to 40 weeks3rd Trimester = Up to 40 weeks• Tremendous amount of growth of the foetus1• The foetus is active – e.g. kicking, stretching limbs, turning.• The eyes will open and close from about Week 32.• The lungs mature so they can function at birth.• The foetus gets ready for birth by turning its head –down.

25






PregnancyPregnancy


BirthBirth


1. PregnancyClick to open link and watch the start of pregnancy then answer the questions: http://www.youtube.com/watch?v=QHLG-Ari9NA1. When does the developing human become a foetus?

26

Feedback to Question 1: At about the second month.

2.When do muscular movements begin in the developing human?

3. What structure develops early after implantation to assist with nutrition and exchange of gases and waste?

Feedback to Question 2: By the fourth month.

Feedback to Question 3: The placenta.

CHECK

CHECK

CHECK






PregnancyPregnancy


BirthBirth


2. Changes during Pregnancy – Hormone secretion

1. What causes changes during pregnancy?

27

You perhaps remember that the corpus luteum secretes progesterone? However, the majority of the progesterone secreted during pregnancy is not triggered by the corpus luteum. In the video you heard that it is done by the placenta. Let's find out what is the placenta

Hormones and in particular, the ‘pregnancy hormone’ which is progesterone.

2. Where does the progesterone come from?

Answer 2Answer 2

Answer 1Answer 1






PregnancyPregnancy


BirthBirth


2. Changes during Pregnancy - The PlacentaQuestion 2.1

• After implantation, some of the dividing cells form fingerlike projections that dig into the endometrium of the uterine wall.

• These fingerlike projections along with the mother’s tissue that surrounds them form the placenta.

• The placenta performs several roles including an endocrine one; it secretes progesterone.

Question 2.1 Describe some of its other functions.

28CHECKCHECK






PregnancyPregnancy


BirthBirth


2. Changes during Pregnancy - The Placenta Feedback to Question 2.1

Feedback to Question: Describe some of the placenta’s other functions•The umbilical cord, which contains blood vessels, extends from the placenta and attaches the foetus to the placenta. •The placenta facilitates the exchange of materials between the mother and foetus via the umbilical cord, e.g. nutrients and oxygen diffuse from the mother to the foetus; carbon dioxide and other waste from the foetus diffuse in the opposite direction. •The placenta is also a barrier to some pathogens and harmful materials.

29






PregnancyPregnancy


BirthBirth


2. Changes during PregnancyQuestion 2.2

2. Suggest the importance of the changes that occur during pregnancy.

30

Feedback:• The breasts enlarge as the mammary glands expand to facilitate milk production. • The uterine wall actually grows new cells so that it can expand to hold the foetus. • The high levels of progesterone inhibit the production of FSH and LH and this

ensures that no more eggs are ovulated from the ovaries, so the menses stop temporarily during pregnancy.

• The placenta continues to support the foetus throughout gestation (the nine months of pregnancy).

• The abdomen expands to facilitate the growth of the foetus. (See next slide)CHECK






PregnancyPregnancy


BirthBirth


2. Changes during Pregnancy

31

Position of stomach

Bladder

Feedback to Question: •As the foetus grows and takes up more and more space, it pushes upwards against her stomach – see line 9 right up where her stomach would be. This prevents her from being able to eat a large amount of food at one time. So, she must eat several much smaller meals across the day.• As the foetus pushes against her bladder, it causes her to have to empty it more frequently, so she will urinate much more frequently than before.

The red lines show the changes in a woman’s uterus and abdomen size to accommodate the growing foetus.Question 2.3: What effect do you think this enlargening foetus has on her ability to eat a large meal or on the frequency of passing urine?

CHECK






PregnancyPregnancy


BirthBirth


Career Focus

Read about the work of an obstetrician.• “An obstetrician is a medical doctor who specializes in the

care of pregnant women from the time of conception through to childbirth and the immediate postnatal period. Obstetricians have surgical skills, which enable them to perform caesareans when required. They also have special skills that allow them to perform diagnostic and screening tests…. Some obstetricians do further training to become specialists in specific areas, such as high-risk pregnancies or infertility. Most obstetricians are also gynaecologists. “

• In Jamaica, we generally speak of these latter persons as ‘O and G’ doctors, but in many countries, these physicians are commonly referred to as ‘OB/GYNs’.

32






PregnancyPregnancy


BirthBirth


2. Changes during PregnancyHow the foetus changes

Click and watch the changes to the foetus in the second and third trimesters at the sites below:

•http://www.youtube.com/watch?v=DOPQYRPRk8s&feature=relmfu•http://www.youtube.com/watch?v=KJiYBryprcE&feature=relmfu

33






PregnancyPregnancy


BirthBirth


3. Birth

Pregnancy or gestation normally ends with labour and then birth. Click and watch this animation from - http://www.youtube.com/watch?v=duPxBXN4qMg&feature=relmfu

Have you ever wondered what causes a woman to go into labour? Hormones again! Yes, the onset of labour and birth is controlled by yet another hormone.

34






PregnancyPregnancy


BirthBirth


3. Birth

• When the foetus is large and it becomes uncomfortable to remain in such a small space (usually at about 40 weeks), the foetus pushes against the uterus, so, stretch receptors in the uterine wall start to send signals to the pituitary gland in the brain.

• The pituitary stimulates the secretion of the hormone oxytocin.

• The hormone stimulates the muscles of the uterus to contract even further.

35






PregnancyPregnancy


BirthBirth


3. Birth

• So, the stimulus is enhanced and the receptors in the distorted uterus continue to send signals to the brain, and it continues to stimulate the secretion of even more oxytocin.

• This positive feedback loop is what sustains contractions during labour. Remember --- a positive feedback is when the response enhances the original stimulus.

36






PregnancyPregnancy


BirthBirth


3. BirthA positive feedback loop

Remind yourself by clicking and following the sequence of events at http://radiantbeginnings.net/2012/05/03/positive-feedback-system-in-labour/

37






PregnancyPregnancy


BirthBirth


3. Birth – The stages

A woman knows her ‘bundle of joy’ is about to come into the world when uterine contractions start, the amniotic sac or ‘the water-bag’ bursts and the amniotic fluid runs out as the ‘show of water’. Click and watch this from > http://www.youtube.com/watch?NR=1&v=u9xfu1qOJzs&feature=endscreenQuestion 1. List the stages of birth in the box below and then click the next button for feedback.

38






PregnancyPregnancy


BirthBirth


Feedback to Question 1List the stages of birth.

The following occur as birth takes place:• Contractions of the uterus begin and dilation of

the cervix and birth canal follows.• Amniotic sac breaks and fluid runs out and the

baby is delivered normally, head first., with its umbilical cord which is then tied/clamped and cut.

• Expulsion of placenta or “afterbirth”.• The diagrams on the next slide summarize the

stages of birth.

39






PregnancyPregnancy


BirthBirth


3. Birth – The stages

These illustrations summarize the Stages of Birth .

40






PregnancyPregnancy


BirthBirth


3. Birth – Delivery cuts

• Sometimes the mother is given a cut in the perineum to prevent tearing, as a surgical cut will heal better than jaggedly torn flesh.

• If there is a problem with normal, vaginal delivery, the mother’s abdomen is cut and the baby taken out. This is a caesarian section commonly called a ’C-section’.

• Read more at the following link: http://www.babycenter.com/2_live-birth-c-section-surgery_3656510.bc

41






PregnancyPregnancy


BirthBirth


3. Birth –The cry of life!

• Click and watch this >http://www.youtube.com/watch?v=AqG_-

DMSyws&feature=relatedYou think that something must be wrong with this baby why he’s crying, don’t you? Well, No! Nothing’s wrong. That’s a cry of life!

• That cry tells the harassed mother, anxious father and expectant family and the delivery team that a new life has come into this world.

• A baby must cry as soon as s/he is born to take air into the lungs and start to breath on its own. So, as is the norm, this baby is celebrating life with its first cry!

42






PregnancyPregnancy


BirthBirth


3. Birth - Summary

• Click to watch the animation which summarizes the content covered in this slide set - http://www.youtube.com/watch?v=qhrZj2RuNgQ&feature=related

• NOTE: You can read about various topics at -• http://bookmark.sunfinedata.com/www-

content/book/ebooks/online%20biology/BioBookREPROD.html

• If every thing has gone well – ovulation, fertilization, implantation, pregnancy and birth - check the next slide to see the result!

43






PregnancyPregnancy


BirthBirth


3. Birth – New-born Baby Caleb

Here’s the kind of prize that parents get for all that waiting for nine long months! This is new-born Baby Caleb!! He weighed over 8 lbs when he was delivered -- normal and healthy at birth.

44

© 2012, Christopher Edwards,






PregnancyPregnancy


BirthBirth


4. After birth

• After the baby is delivered, the placenta is useless, so, it also is expelled by uterine contractions. If not, it can cause complications that can lead to death of the mother.

• The baby is given a vitamin K injection immediately after birth to help with blood clotting.

• The baby can be sent home once the first stool, meconium, is passed

45






PregnancyPregnancy


BirthBirth


4. After birth

• Oxytocin causes milk to be secreted from the breasts especially under stimulation from sucking by the baby.

• The vagina and uterus gradually contract.• The menstrual cycle will start again later.

46






PregnancyPregnancy


BirthBirth


Menopause• “Menopause occurs as the ovaries stop producing

estrogen, causing the reproductive system to gradually shut down. As the body adapts to the changing levels of natural hormones, vasomotor symptoms such as hot flashes and palpitations, psychological symptoms such as increased depression, anxiety, irritability, mood swings and lack of concentration, and atrophic symptoms such as vaginal dryness and urgency of urination appear. Together with these symptoms, the woman may also have increasingly scanty and erratic menstrual periods.

• Technically, menopause refers to the cessation of menses; whereas the gradual process through which this occurs, which typically takes a year but may last as little as six months or more than five years.”

47






PregnancyPregnancy


BirthBirth


QUICK QUIZ

Try these Quizzes online!

• http://sensiblescience.com/quizzes/female-reproductive-system.html

• http://www.funtrivia.com/newflash/trivia.cfm?qid=264854

• http://www.funtrivia.com/newflash/trivia.cfm?qid=142336

48






PregnancyPregnancy


BirthBirth


End of Activity

• You have reached the end of the Power point slide presentation.

• If you wish to review any of the concepts in this lesson, go to the first slide.

• If you have finished viewing the lesson, click the Close (X) button.

4949

Education

Integrated Science M3 Fertilization, Pregnancy and birth