Introduction to Embryology Flashcards Preview

Anatomy Test One Material > Introduction to Embryology > Flashcards

Flashcards in Introduction to Embryology Deck (63)
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1

What is the embryonic period?

Fertilization to 8 weeks (56 days)

2

What is the fetal period?

9th week (57 days) to term (38th week)

3

What generally happens during the embryonic period?

Initial development of all major structures and establishment of all organ systems.

4

What generally happens during the fetal period?

Differentiation and growth of organs and tissues.

5

During interphase the cell has how many sets of chromosomes?

2N

6

Preprophase the cell has how many sets of chromosomes?

4N

7

During mitotic prophase, metaphase, anaphase, and telophase the cell has how many sets of chromosomes?

4N

8

During mitosis cytokinesis the cell has how many sets of chromosomes?

2N

9

During meiosis 1 preprophase the cell has how many sets of chromosomes?

4N

10

During meiosis 1 prophase 1, metaphase 1, anaphase 1, and telophase 1 the cell has how many sets of chromosomes?

4N

11

During meiosis 1 cytokinesis 1 the cell has how many sets of chromosomes?

2N

12

During meiosis 2 prophase 2 through telophase 2 the cell has how many sets of chromosomes?

2N

13

During meiosis 2 cytokinesis 2 the cell has how many sets of chromosomes?

1N

14

How many sets of chromosomes does an unfertilized oocyte have?

1N

15

How many sets of chromosomes does a spermatid have?

1N

16

Primordial sex cells (germ cells) originate as what?

Specific cells lining the yolk sac (umbilical vesicle)

17

How many sets of chromosomes do primordial sex (germ cells) cells have?

Diploid 2N

18

Where do the primordial sex cells (germ cells) initially migrate?

They migrate to occupy gonads and mature into gametes (mature sex cells: spermatozoa & oocyte)

19

The genital ridge is also called what?

the gonadal ridge

20

What happens during gametogenesis?

This is a process that reduces chromosomal number by 1/2. Diploid to haploid. 2N to N.

21

What is spermatogenesis?

Spermatogonia to sperm (begins at puberty)

22

What is oogenesis?

Oogonia to oocyte (begins BEFORE birth, halts, continues at puberty)

23

How many oocytes does a female have at three months in the womb?

About 2 million

24

How many oocytes does a female have at five months in the womb?

About 7 million

25

How many oocytes does a female have at birth?

About 600 to 800 thousand

26

How many oocytes does a female have at menarche?

About 400 thousand

27

Are mature sperm 23X or 23Y?

They can be one or the other.

28

Are mature oocytes 23X or 23Y?

They are all 23X.

29

What is the outer most layer of the oocyte called?

Corona radiata

30

What is the layer of an oocyte just deeper than the corona radiata?

The zona pellucida