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Repreductive System
Chapter 23
Question | Answer |
---|---|
fusion of male and female pronuclei | fertilization |
solid ball of embryonic cells | morula |
process of rapid mitotic cell division without intervening growth periods | cleavage |
combination of egg and sperm | zygote |
process involving cell rearrangement to form the three primary germ layers | gastrulation |
embryonic stage in which the embryo consists of a hollow ball of cells | blastula |
(Blank) embryonic stage in which the embryo consists of a hollow ball of cells | ICM |
(Blank)becomes the chorion and cooperates with the uterine tissue to form the placenta | trophoblast |
(Blank)produces the amnion, yolk sac, and allantois | placenta |
(Blank)produces the primordial germ cells (an embryonic membrane) | epiblast |
(Blank)an embryonic membrane that provides the structural basis for the body stalk or umbilical cord | mesoderm |
How many days after ovulation is implantation generally completed? | six to seven days |
. What event in the female menstrual cycle ordinarily occurs just about this time if implantation does not occur? | miscarry |
What name is given to the part of the uterine wall directly under the implanting embryo? | endometrium |
That surrounding the rest of the embryonic structure? | amnion |
Which two organ systems are extensively developed in the very young embryo? | (blank) |
the direction of development | (blank) |
When does the human embryo come to be called a fetus? In week number | (blank) |
What is the tissue origin of the placenta? | (blank) |
Define zygote | A zygote is a fertilized egg that occurs after a sperm and egg fuse together. Zygotes contain 23 pairs of homologous chromosomes or diploid chromosome number of 46. |
Cleavage is | Cleavage is (embryology) the repeated division of a fertilized ovum. |