gestation

Question 1

embryonic period-week 1

Answer 1

-first eight weeks of development
-fertilization
-zygote
-morula
-blastocyst

Question 2

fertlization

Answer 2

merging of genetic information from sperm cell and oocyte

Question 3

zygote

Answer 3

fertilised egg divides into two cells

Question 4

morula

Answer 4

cluster of cells by day 4

Question 5

blastocyst

Answer 5

32 cell mass with fluid-filled cavity

Question 6

embryonic period-week 2

Answer 6

-chorion becomes a principle part of the placenta

Question 7

how does the placenta protect the embryo from the mother’s immune system

Answer 7

-secreting proteins to block mother’s antibodies
-producing T cells (leukocytes) to suppress mother’s immune response

Question 8

embryonic period-week 3

Answer 8

-gastrulation
-neurulation
-angiogenesis

Question 9

gastrulation

Answer 9

embryonic disc splits into three germ layers:
1. ectoderm
3. mesoderm
3. endoderm

Question 10

ectoderm becomes…

Answer 10

1. digestive system
2. liver
3. pancreas
4. lungs (inner layers)

Question 11

mesoderm becomes…

Answer 11

1. circulatory system
2. lungs (epithelial layers)
3. skeletal system
4. muscular system

Question 12

ectoderm layer

Answer 12

1. hair
2. nails
3. skin
4. nervous system

Question 13

neurulation

Answer 13

cellular components of the nervous system start to form (neural crest, tube and plate)

Question 14

angiogenesis

Answer 14

the formation of blood vessels

Question 15

embryonic period-week 4-8

Answer 15

-organogenesis
-embryonic folding

Question 16

organogenesis

Answer 16

major organs developing

Question 17

embryonic folding

Answer 17

embryo folds into a 3D cylinder in week 4, bone formation, major blood vessels and blood cells start to form

Question 18

embryonic period-week 9-36

Answer 18

-tissues and organs grow and differentiate

Question 19

by week 12

Answer 19

the placenta divides into feotal (chorion) and maternal portions

Question 20

what does the placenta do?

Answer 20

-stores and diffuses nutrients
-excretes wastes into maternal blood
-mediates exchange of oxygen, carbon dioxide and hormones between mother and fetus

Question 21

feotal circulatory system

Answer 21

-umbilical cord
-umbilical vein
-umbilical arteries
-shunt

Question 22

umbilical cord

Answer 22

contains one umbilical vein and two umbilical arteries

Question 23

umbilical vein

Answer 23

carries blood (full of nutrients and oxygen) to the fetus

Question 24

umbilical arteries

Answer 24

carries blood (full of waste and carbon dioxide) from the fetus to the placenta

Question 25

shunt

Answer 25

anatomical diversion to bypass immature organs, present in the heart and liver

Question 26

week 12

Answer 26

-bone formation -heartbeat detected -gender determined -brain expansion -movement begins -urine secreted

Question 27

week 16

Answer 27

-meconium (faeces) accumulate in the intestines -lower limbs strengthen -body systems develop rapidly

Question 28

week 20

Answer 28

-growth slows down -brown fat forms -movements felt by mother -waxy coat and hair protects skin

Question 29

week 24

Answer 29

-weight gain -pink and wrinkled skin -can survive now if prematurely born

Question 30

week 28

Answer 30

-eyes open -subcutaneous (under the skin) formed -red bone marrow produces red cells -lung and nervous systems can control breathing/blood temperature -'practise' breathing

Question 31

week 32

Answer 31

-smooth skin -upside down position -8% fat

Question 32

week 36

Answer 32

-abdomen circumference bigger than the head -growth slows down further -16% body fat

Question 33

prenatal diagnostic tests

Answer 33

-fetal ultrasonography -amniocentesis -abnormalities -chronic villus sampling -maternal alpha-fetoprotein (AFP)

Question 34

fetal ultrasonography

Answer 34

can detect -fetal age -position -confirm pregnancies (or multiple pregnancies

Question 35

amniocentesis

Answer 35

-analyse amniotic fluid -analyse feotal cells for genetic abnormalities -by using a needle guided by ultrasound

Question 36

chorionic villus sampling

Answer 36

-analyse amniotic fluid -analyse feotal cells for genetic abnormalities -reveal genetic abnormalities

Question 37

maternal alpha-fetoprotein (AFP)

Answer 37

-uses a blood sample from the mother -detects if AFP is present after 16 weeks -indicates neural tube defect