Embryology

Question 1

The term ecto refers to ____.

Answer 1

outside

Question 2

The ___ somite will eventually from skin fro the embryo

Answer 2

dermatome

Question 3

An ovum develops the size of a yolk by collecting lipid particles that were made in the hen’s ___ from the blood

Answer 3

liver

Question 4

If the hen does not receive enough __ and __ in the feed, she will not make an egg

Answer 4

calcium and phosphorus

Question 5

When fertilization occurs, embryonic development begins and continues for the __hours that it takes to form an egg in the hen

Answer 5

24 hours

Question 6

At about __hours of incubation, blood vessels coming from the embryo join with those coming from the area opaca, replacing this area with the yolk sac

Answer 6

48 hours

Question 7

the extraembryonic membranes are __ of the embryo and never become part of it

Answer 7

outside

Question 8

Which membrane is visible when a chick first hatches as it lies next to the shell

Answer 8

chorioallantoic

Question 9

it is expected that more than __ sequences will be discovered in the chicken genome

Answer 9

20,000

Question 10

formation of the central nervous Sstem is dependent upon the __

Answer 10

neural tube

Question 11

Less than __ of the chicks with head in wrong part of the egg malposition hatch

Answer 11

One half

Question 12

all of the parts of a chick are in place by day __ of incubation

Answer 12

10 days

Question 13

The correct position for a chicken embryo to be in the egg is ___

Answer 13

head tucked under right wing located toward round (large) end of egg

Question 14

the most common standard for the developing chick embryo was prepared by ___, who divided the standard into 45 stages

Answer 14

hamburger and Hamilton

Question 15

The neural __ is a region that folds inward to form the neural tube

Answer 15

plate

Question 16

the inner part of the blastoderm is hollowed out and is ___ indicating that light can pass through it to give is an almost transparent appearance

Answer 16

Pellucida

Question 17

Another category of defects is called __ in chickens and birth defects in humans

Answer 17

malformations

Question 18

the outer part of the blastoderm is ___ meaning not much light can pass through

Answer 18

opaca

Question 19

At about day ___ of incubation, the embryo has used much of the yolk

Answer 19

19

Question 20

when does cell division begin for the embryo

Answer 20

fertilization

Question 21

The __ catche steh yolk, which then starts its journey through the oviduct to add the albumen and shell

Answer 21

infundibulum

Question 22

cell division for the embryo starts from the back of the pellucida and creates a thin layer of cells as it moves in a forward direction, creating a ___

Answer 22

triangle

Question 23

When the egg is laid, the blastoderm can be compared to a ___

Answer 23

doughnut

Question 24

A small white dot called the __ is attached to the vitelline membrane and contains the genetics information that is supplied by the female

Answer 24

blastodisc

Question 25

which of the following is not a function of the chorioallantocia membrane

Answer 25

provide nutrients to the growing embryo

Question 26

a healthy embryo will cause the egg to have a ___ appearance when candled

Answer 26

red

Question 27

once a chick hatches, what happens to the solid waste a chick excretes during incubation

Answer 27

remains on the shell

Question 28

which two factors can impact embryonic development

Answer 28

genetics and nutrients

Question 29

once the cells have buckled and formed the primitive groove the primitive streak I snow shaped like a ___

Answer 29

pear

Question 30

one of the membranes that forms soon after incubation which appears as a sac on the outside of the embryo is called the ___

Answer 30

allantois

Question 31

the term meso refers to ___

Answer 31

middle

Question 32

as the cells continue to bunch an move toward the middle of the area pellucida on the blastoderm they cause buckling and create a ___

Answer 32

primitive groove

Question 33

the term ending refers to ___

Answer 33

inside

Question 34

when the egg is laid and the temperature drops below ___, cell division stops until the egg is brought to incubation temperature

Answer 34

85 degrees

Question 35

in commercial poultry, the combination of malposition and malformations decrease the overall hatchablility at about __ percent

Answer 35

5%

Question 36

on of the membranes that is formed soon after incubation and extends around the embryo and lies next to the shell is called ___

Answer 36

chorion

Question 37

if present, toxic compounds may also enter the egg, either from __ or ___ and these compounds can cause the death of the developing embryo

Answer 37

hen's feed or egg environment

Question 38

when the cells on the triangular wedge of the growing embryo bunch toward the middle and form a concentration of cells that is called the ___

Answer 38

primitive streak

Question 39

during the last few days of incubation when the yolk sac absorbed and the chick begins to breath, an increase in __ muct occur

Answer 39

humidity

Question 40

producing the right amount of each __ t the right time is what regulates development and life

Answer 40

sugar

Question 41

the chorion membrane fuses with the allantois membrane to form __

Answer 41

chorioallantoic membrane

Question 42

what happens to the yolk that is not used by the embryo ?

Answer 42

absorbed in chick's abdomen

Question 43

After __ days of incubation, cartilage is present

Answer 43

8 day

Question 44

in about ___, an ovum develops to the size of a yolk by collecting lipid particles

Answer 44

1 week

Question 45

the egg must have the proper amounts of about ___ different nutrients for the embryo to develop

Answer 45

40

Question 46

by day __ of incubation all of the muscle groups present in an adult have been established

Answer 46

10 day

Question 47

after __ to __ days of incubation, the embryo appears to be floating in a bed of water, which helps prevent injury to the embryo and keeps the embryo bathed in fluid

Answer 47

4-6 days

Question 48

a very serious malposition is __

Answer 48

head toward pointed end of egg

Question 49

myotome rom somites 27 through 32 form the __ muscles

Answer 49

leg

Question 50

by the time the hen lays the egg, enough embryonic cells have formed to be visibly changed, the blastodisc has changed into the ___

Answer 50

blastoderm

Question 51

the cells of the triangular wedge in the area pellucida move towards the middle of the area in a process called __

Answer 51

gastrulation

Question 52

yolk contents are retained by the ___

Answer 52

vitelline membrane

Question 53

the somites exist for only __ days

Answer 53

few

Question 54

eventually the embryo will have ___ pairs of somites after about ___ hours of incubation

Answer 54

22; 55

Question 55

what provides the first physical evidence that an egg is fertile ?

Answer 55

blood vessels on the yolk sac seen

Question 56

one of the membranes that is formed soon after incubation and forms under the embryo and collects water from the albumen is the ___

Answer 56

amnion

Question 57

There are more than ___ vertebrae in the newley hatched chick, and some vertebrae attach to ribs

Answer 57

40

Question 58

the area __ is the part of the blastoderm from which the embryo development

Answer 58

pellucida

Question 59

Having __ is one malposition and it is not as serious

Answer 59

head on outside of head

Question 60

once the yolk sac is absorbed b the embryo, the __ becomes the main source of nutrition fro the embryo

Answer 60

yolk

Question 61

cells from they myotome somites form leg Buds between days __ and __

Answer 61

6, 8

Question 62

if the embryo is not positioned correctly , the condition is known as ___

Answer 62

malposition

Question 63

the first pair of somites appear at about __ hours of incubation

Answer 63

24

Question 64

around day __, an increase number of embryos die, with an even larger percentage at day ___

Answer 64

4; 18

Question 65

the sperm will locate the ___ and penetrate it in the process of fertilization

Answer 65

blastodisc

Question 66

when the yolk is the correct size, it is released from the ovary to the hen's ___

Answer 66

abdomen

Question 67

if the female has mated within the last few weeks , sperm should be present in the ___.

Answer 67

infundibulum

Question 68

more than ___ specific kinds of defects have been identified, which commonly affect the skeleton, parts of the head, wings, and legs

Answer 68

40

Question 69

supporting structures called extraembryonic membrane develop mostly in the area __ of the blastoderm

Answer 69

opaca

Question 70

deficiencies in the hen's diet such as __ and __ can impact embryonic development

Answer 70

minerals and vitamins

Question 71

the white spots are __ tat were caused b the sperm that penetrated the egg's vitelline membrane

Answer 71

bullet holes

Question 72

An ___ egg has a dark middle caused by the yolk when candled

Answer 72

infertile