Human Development

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1

Back 1

1. Secondary oocyte

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Back 2

2. Fertilization of secondary oocyte

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Back 3

3. 2-cell stage

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Back 4

4. 4-cell stage

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Back 5

5. Morula

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Back 6

6. Blastocyst

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Back 7

7. Implantation of blastocyst

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1

Back 8

1. Yolk sac

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2

Back 9

2. Amnion

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3

Back 10

3. Amniotic cavity

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4

Back 11

4. Bilaminar embryonic disc

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1

Back 12

1. Amniotic cavity

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2

Back 13

2. Embryo

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3

Back 14

3. Yolk sac

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4

Back 15

4. Connecting stalk

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4

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4. Connecting stalk

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5

Back 17

4. Chorionic villus

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1

Back 18

1. Chorionic villi

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2. Fetal blood vessels

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Back 20

3. Decidua basalis

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Back 21

4. Chorion

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5

Back 22

5. Umbilical arteries

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5

Back 23

5. Umbilical arteries

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6

Back 24

6. Umbilical veins