©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
NU404 Unit 3 Study Guide with Complete
Solutions
Fetal development is measured by the number of _________ after fertilization - Ans:✔✔-Weeks
Pregnancy is divided into ________ trimesters - Ans:✔✔-Three
An average human pregnancy lasts __________ weeks from the date of the last menstrual period -
Ans:✔✔-40
1st Trimester - Ans:✔✔-Month (0-3)
Weeks (0-13)
2nd Trimester - Ans:✔✔-Month (3-6)
Weeks (14-27)
3rd Trimester - Ans:✔✔-Month (6-9)
Weeks (28-42*)
Preembryonic stage - Ans:✔✔-fertilization through the second week
Page 1/19
, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
Embryonic stage - Ans:✔✔-end of the 2nd week through the 8th week
Fetal stage - Ans:✔✔-end of the 8th week until birth
Conception - Ans:✔✔-The pre-embryonic stage begins with fertilization
The gametes (ovum or sperm cells) must each have a set of _______ chromosomes - Ans:✔✔-23
A zygote has ______ chromosomes - Ans:✔✔-46
Sex determination and genetic information is determined at fertilization and depends on - Ans:✔✔-
whether the ovum is fertilized by a Y-bearing sperm (boy) or an X-bearing sperm (girl)
An XX zygote? - Ans:✔✔-female
An XY zygote? - Ans:✔✔-male
Identical Twins - Ans:✔✔-Occurs when one fertilized egg splits and develops into two
Fraternal twins - Ans:✔✔-Two seperate eggs are fertilized by two different sperm
Implantation - Ans:✔✔-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 - Ans:✔✔-embryo
Page 2/19
, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
Chorion - Ans:✔✔-outermost membrane of embryo
Amnion - Ans:✔✔-Innermost thin protective membrane over the embryo that contains amniotic fluid
Di-Di (best case scenario) - Ans:✔✔-2 chronic sacs
2 amniotic sacs
2 placentas
2 fetuses
2 umbilical cords
Mo-Di (slight risk) - Ans:✔✔-1 chorionic sac
2 amniotic sacs
1 placenta
2 fetuses
2 umbilical cords
Mo-Mo (highest risk) - Ans:✔✔-1 chorionic sac
1 amniotic sac
Page 3/19
FIRST PUBLISH OCTOBER 2024
NU404 Unit 3 Study Guide with Complete
Solutions
Fetal development is measured by the number of _________ after fertilization - Ans:✔✔-Weeks
Pregnancy is divided into ________ trimesters - Ans:✔✔-Three
An average human pregnancy lasts __________ weeks from the date of the last menstrual period -
Ans:✔✔-40
1st Trimester - Ans:✔✔-Month (0-3)
Weeks (0-13)
2nd Trimester - Ans:✔✔-Month (3-6)
Weeks (14-27)
3rd Trimester - Ans:✔✔-Month (6-9)
Weeks (28-42*)
Preembryonic stage - Ans:✔✔-fertilization through the second week
Page 1/19
, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
Embryonic stage - Ans:✔✔-end of the 2nd week through the 8th week
Fetal stage - Ans:✔✔-end of the 8th week until birth
Conception - Ans:✔✔-The pre-embryonic stage begins with fertilization
The gametes (ovum or sperm cells) must each have a set of _______ chromosomes - Ans:✔✔-23
A zygote has ______ chromosomes - Ans:✔✔-46
Sex determination and genetic information is determined at fertilization and depends on - Ans:✔✔-
whether the ovum is fertilized by a Y-bearing sperm (boy) or an X-bearing sperm (girl)
An XX zygote? - Ans:✔✔-female
An XY zygote? - Ans:✔✔-male
Identical Twins - Ans:✔✔-Occurs when one fertilized egg splits and develops into two
Fraternal twins - Ans:✔✔-Two seperate eggs are fertilized by two different sperm
Implantation - Ans:✔✔-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 - Ans:✔✔-embryo
Page 2/19
, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
Chorion - Ans:✔✔-outermost membrane of embryo
Amnion - Ans:✔✔-Innermost thin protective membrane over the embryo that contains amniotic fluid
Di-Di (best case scenario) - Ans:✔✔-2 chronic sacs
2 amniotic sacs
2 placentas
2 fetuses
2 umbilical cords
Mo-Di (slight risk) - Ans:✔✔-1 chorionic sac
2 amniotic sacs
1 placenta
2 fetuses
2 umbilical cords
Mo-Mo (highest risk) - Ans:✔✔-1 chorionic sac
1 amniotic sac
Page 3/19
