History of embryology

Question 1

Hippocrates

Answer 1

“father of medicine”

earliest recorded embryologic studies

Question 2

Aristotle

Answer 2

“founder of embryology”

described development of chick

Question 3

Spontaneous Generation Theory

Answer 3

“new life arises from slime and decaying matter”

ex. maggots appearing on cadavers

Question 4

Jacob Rueff

Answer 4

suggested fetus developed from coagulum of blood and semen in uterus

Question 5

Preformation Theory

Answer 5

suggested completely formed tiny homunculus contained within sperm and ovum

Question 6

Epigenesis Theory

Answer 6

“since eggs lack internal organization, some outside force causes development through use of cells”

Question 7

Germ Layer Theory

Answer 7

proposed 3 germ layers

Question 8

Von Baer

Answer 8

“father of modern embryology”

described the oocyte in the ovarian follicle of a dog

Question 9

Schleiden and Schwann

Answer 9

formulated cell theory

Question 10

Haeckel

Answer 10

“ontogeny recapitulates phylogeny”–>life of an individual reflects life of entire species
Recapitulation Theory
Biogenetic Law

Question 11

Biogenetic Law

Answer 11

each embryo in its development passes through abbreviated stages that resemble developmental stages of evolutionary ancestors

Question 12

Charles Darwin

Answer 12

“Origin of Species”

emphasized hereditary nature of variability

Question 13

Gregor Mendel

Answer 13

described principles of heredity, dominant and recessive traits

Question 14

Walter Fleming

Answer 14

described chromosomal behavior during animal cell division

Question 15

Felix von Winiwarter

Answer 15

first observed human chromosome

Question 16

Tijo and Levan

Answer 16

reported 46 chromosomes in embryonic cells

Question 17

James Watson and Francis Crick

Answer 17

deciphered molecular structure of DNA

Question 18

Lejeune

Answer 18

discovered cause of some congenital abnormalities as abnormal chromosome number

Question 19

chimaera

Answer 19

mixed-sex human embryo

Question 20

amniocentesis

Answer 20

prenatal diagnostic tool
can determine maturity of lungs of fetus, diagnose or rule out uterine infection, or determine chromosomal or genetic abnormalities

Question 21

chorionic villus sampling (CVS)

Answer 21

prenatal diagnostic tool

can detect up to 200 genetic or chromosomal diseases

Question 22

beginning of fetal period

Answer 22

8th week

Question 23

true age

Answer 23

counts from time of fertilization or conception

~38 weeks total

Question 24

ovulation age

Answer 24

true age + 1 day

Question 25

copulation age

Answer 25

true age + 1-3 days

Question 26

menstrual/gestational age

Answer 26

true age + 14 days

counts from time of last menstrual period

Question 27

embryology

Answer 27

anatomy subspecialty, restricted to developmental processes during prenatal period

Question 28

fetology

Answer 28

obstetrics subspecialty

study, diagnosis, and treatment of fetus in utero

Question 29

perinatology

Answer 29

=maternal/fetal medicine
obstetrics subspecialty
study, diagnosis, and treatment of fetus/newborn from 20-28 weeks of gestation to 4 weeks after birth

Question 30

neonatology

Answer 30

pediatrics subspecialty

study, diagnosis, and treatment of newborn during first 4 weeks of life

Question 31

Greatest Length (GL)

Answer 31

used during embryonic period

Question 32

Crown-Rump Length (CRL)

Answer 32

sitting height, used during embryonic period

measure from head to buttocks

Question 33

Crown-Heel Length (CHL)

Answer 33

standing height, used during fetal period

Question 34

chorionic sac first seen

Answer 34

~13 days

Question 35

beginning of heartbeat

Answer 35

21-23 days

Question 36

Biparietal Diameter

Answer 36

measurement across skull between 2 parietal bones

Question 37

anlage of extremities

Answer 37

5th week

Question 38

anlage of all basic organ systems

Answer 38

10th week