NU404 Unit 3 Test Guide With
Complete Solution
Fetal development is measured by the number of _________ after fertilization -
ANSWER Weeks
Pregnancy is divided into ________ trimesters - ANSWER Three
An average human pregnancy lasts __________ weeks from the date of the last
menstrual period - ANSWER 40
1st Trimester - ANSWER Month (0-3)
Weeks (0-13)
2nd Trimester - ANSWER Month (3-6)
Weeks (14-27)
3rd Trimester - ANSWER Month (6-9)
Weeks (28-42*)
Preembryonic stage - ANSWER fertilization through the second week
Embryonic stage - ANSWER end of the 2nd week through the 8th week
Fetal stage - ANSWER end of the 8th week until birth
Conception - ANSWER The pre-embryonic stage begins with fertilization
The gametes (ovum or sperm cells) must each have a set of _______
chromosomes - ANSWER 23
,A zygote has ______ chromosomes - ANSWER 46
Sex determination and genetic information is determined at fertilization and
depends on - ANSWER whether the ovum is fertilized by a Y-bearing sperm
(boy) or an X-bearing sperm (girl)
An XX zygote? - ANSWER female
An XY zygote? - ANSWER male
Identical Twins - ANSWER Occurs when one fertilized egg splits and develops
into two
Fraternal twins - ANSWER Two seperate eggs are fertilized by two different
sperm
Implantation - ANSWER Normally, occurs in the upper uterus (fundus) where
a rich blood supply is avaliable
During the embryonic stage the zygote multiplies and divides into an -
ANSWER embryo
Chorion - ANSWER outermost membrane of embryo
Amnion - ANSWER Innermost thin protective membrane over the embryo
that contains amniotic fluid
Di-Di (best case scenario) - ANSWER 2 chronic sacs
2 amniotic sacs
2 placentas
2 fetuses
2 umbilical cords
, Mo-Di (slight risk) - ANSWER 1 chorionic sac
2 amniotic sacs
1 placenta
2 fetuses
2 umbilical cords
Mo-Mo (highest risk) - ANSWER 1 chorionic sac
1 amniotic sac
1 placenta
2 fetuses
2 umbilical cords
Risks of Mo-Mo - ANSWER One singular blood supply, chances of fetal
accident (cord wrapped around baby) extremely high
Di-Di = _________ twins - ANSWER fraternal
Mo-Di and Mo-Mo= _______ twins - ANSWER identical
Longest stage of prenatal development - ANSWER fetal stage
Amniotic fluid surrounds the embryo and increases in volume as the
pregnancy progresses reaching approximately a _________ at term - ANSWER
Liter
Two sources amniotic fluid is derived from - ANSWER maternal blood across
the amnion and fetal urine
Amniotic Fluid - ANSWER helps maintain constant body temp
Complete Solution
Fetal development is measured by the number of _________ after fertilization -
ANSWER Weeks
Pregnancy is divided into ________ trimesters - ANSWER Three
An average human pregnancy lasts __________ weeks from the date of the last
menstrual period - ANSWER 40
1st Trimester - ANSWER Month (0-3)
Weeks (0-13)
2nd Trimester - ANSWER Month (3-6)
Weeks (14-27)
3rd Trimester - ANSWER Month (6-9)
Weeks (28-42*)
Preembryonic stage - ANSWER fertilization through the second week
Embryonic stage - ANSWER end of the 2nd week through the 8th week
Fetal stage - ANSWER end of the 8th week until birth
Conception - ANSWER The pre-embryonic stage begins with fertilization
The gametes (ovum or sperm cells) must each have a set of _______
chromosomes - ANSWER 23
,A zygote has ______ chromosomes - ANSWER 46
Sex determination and genetic information is determined at fertilization and
depends on - ANSWER whether the ovum is fertilized by a Y-bearing sperm
(boy) or an X-bearing sperm (girl)
An XX zygote? - ANSWER female
An XY zygote? - ANSWER male
Identical Twins - ANSWER Occurs when one fertilized egg splits and develops
into two
Fraternal twins - ANSWER Two seperate eggs are fertilized by two different
sperm
Implantation - ANSWER Normally, occurs in the upper uterus (fundus) where
a rich blood supply is avaliable
During the embryonic stage the zygote multiplies and divides into an -
ANSWER embryo
Chorion - ANSWER outermost membrane of embryo
Amnion - ANSWER Innermost thin protective membrane over the embryo
that contains amniotic fluid
Di-Di (best case scenario) - ANSWER 2 chronic sacs
2 amniotic sacs
2 placentas
2 fetuses
2 umbilical cords
, Mo-Di (slight risk) - ANSWER 1 chorionic sac
2 amniotic sacs
1 placenta
2 fetuses
2 umbilical cords
Mo-Mo (highest risk) - ANSWER 1 chorionic sac
1 amniotic sac
1 placenta
2 fetuses
2 umbilical cords
Risks of Mo-Mo - ANSWER One singular blood supply, chances of fetal
accident (cord wrapped around baby) extremely high
Di-Di = _________ twins - ANSWER fraternal
Mo-Di and Mo-Mo= _______ twins - ANSWER identical
Longest stage of prenatal development - ANSWER fetal stage
Amniotic fluid surrounds the embryo and increases in volume as the
pregnancy progresses reaching approximately a _________ at term - ANSWER
Liter
Two sources amniotic fluid is derived from - ANSWER maternal blood across
the amnion and fetal urine
Amniotic Fluid - ANSWER helps maintain constant body temp
