Fertilisation and pregnancy

Fertilisation & pregnancy
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Slide 1: Slide
BiologieMiddelbare schoolvwoLeerjaar 4

This lesson contains 24 slides, with text slides and 3 videos.

time-iconLesson duration is: 30 min

Items in this lesson

Fertilisation & pregnancy

Slide 1 - Slide

- Questions last lesson
- Explanation fertilization & pregnancy
- Do assignments

Slide 2 - Slide

- During which days of a typical 28 day menstrual cycle does the follicular phase occur?
- If the ovum is to be fertilised, where is the most common site of fertilisation?
- What hormone is released from the pituitary gland and stimulates the follicles in the ovary to mature?
- If the ovum is not fertilised, what causes the cycle to end and menstruation to start?

Slide 3 - Slide

Learning objectives
  • You can describe the hormonal changes that occur after fertilisation happens
  • You can describe the hormones involved in pregnancy
  • You can explain how the placenta functions
  • Describe the important stages during pregnancy 

Slide 4 - Slide

Write down for yourself what you see during this video!

Slide 5 - Slide

Slide 6 - Video

Questions about the video?

Slide 7 - Slide

  • Sperm cells carry enzymes

  • Egg cell puts up permanent block

  • Egg cell completes meiosis 2

Slide 8 - Slide

Slide 9 - Slide

Slide 10 - Slide

First period of pregnancy
  • Completion meiosis
  • Cleavage divisions
    - No growth
  • Blastocyst
    - First structures
  • Implantation

Slide 11 - Slide

First period of pregnancy
  • Cleavage divisions
    - No growth
  • Blastocyst
    - First structures
  • Implantation

Slide 12 - Slide

  • Embryo gets nutrients from the endometrium
  • The trophoblast invades the endometrium
  • The placenta is being formed

Slide 13 - Slide

Placenta development
  • Formed by embryo and mother together
  • Exchange of nutrients and waste
  • No direct blood contact!

Slide 14 - Slide

Exchange of nutrients/ waste/O2
  • O2, CO2 , nutrients  and wastes via diffusion, selective absorption and active transport
  • between the fetal capillary beds and the maternal blood spaces
  • No mixing of blood!

Slide 15 - Slide

What arteries and veins?
  • One umbilical vein containing O2 rich, CO2 poor, nutrient rich blood
  • Two umbilical arteries containing O2 poor, CO2 rich, nutrient poor and waste rich blood

Slide 16 - Slide

Slide 17 - Slide

The Cuddle Hormone Oxytocin
- Okytokos: Greek for quick birth
- stimulates the contractions
-made by the posterior lob of the pituitary gland
- is being released by both men and women when they cuddle and or have sex
-increases chances on fertilization
- helps parents to bond with their child

Slide 18 - Slide

Slide 19 - Video

Slide 20 - Video

  • First stage
    - Cervix expands
    - Amniotic fluid released
  • Second stage: delivery
    - Actual birth
  • Third stage
    - Expulsion of the placenta

Slide 21 - Slide

  • Nourishment after birth
  • Hormones
    - Prolactin: promotes milk production
    - Oxytocin: stimulates release milk
  • Drinking baby promotes release of prolactin and oxytocin, but inhibits release LH and FSH
    - Lactational anovulation
  • Colostrum: first milk contains many antibodies

Slide 22 - Slide

What are the three hormones that increase during pregnancy?
What hormone stimulates lactation?
What is the hormone that you can detect with a pregnancy test?

Slide 23 - Slide

Work to be done
Assessment Questions Glencoe pg 1069-1070: Q 12-22.

Assessment Questions Glencoe pg 1070 Q: 25-34 +36.
 - Make a summary for yourself in which you describe
all the stages from fertilization to labour (include hormones)
- Do the LessonUp on sexual Diversity (Teams)

Slide 24 - Slide