Major Milestones in Fetal Growth and Development (Test
1) ||Completely solved.
Conception correct answersthe union of a single egg and sperm
Meiosis correct answersthe process of cell division that occurs in the maturation of sperm and
ova that decreases their # of chromosomes by one-half. (from 46 chromosomes to 23). Occurs
during gametogenesis.
Zygote correct answersformed from the male gamete when united with the female gamete.
When ova is considered fertile: correct answers24 hours after ovulation.
How long can sperm survive: correct answersit can survive in the reproductive tract for 48-72
hours.
Process of fertilization: correct answerswhen a sperm fuses with an ovum to form a new diploid
cell or zygote.
High estrogen levels during fertilization: correct answershigh estrogen levels increase peristalsis
within the fallopian tube helping to move the ovum through the tube to the uterus for
implantation in the endometrium.
Intrauterine Development correct answers-the zygote begins cellular multiplication in the
fallopian tube
-changes from blastomeres to the morula
-blastocyst and trophoblast are formed
Trophoblast correct answerseventually develops into the chorion.
Blastocysts correct answerseventually develops into embryo and the amnion.
Implantation (Nidation): correct answers-where the trophoblast attaches to the surface of the
endometrium
-cells of the trophoblast grow into the thickened lining forming villi
-implantation is completed by the 9th day.
Most frequent site of implantation: correct answersupper part of the posterior uterine wall
Progesterone during implantation: correct answersincreases the endometrial thickness and
vascularity in preparation for implantation.
3rd week AFTER conception correct answersthe primary germ layers form.
Time frame of fertilization: correct answers2-3 days
, Time frame of completed implantation: correct answers9th day from conception.
Ectoderm correct answersepidermis, the glands, the nails & hair, CNS/PNS, pituitary glands,
mammary glands
Mesoderm correct answersbones, teeth, muscles, dermis, wall of digestive tract, cardiovascular
system, lymphatic tissue and cells, pleura, spleen
Endoderm correct answersepithelial lining of the respiratory & GI tract, Vagina (parts), urinary
bladder, urethra, epithelium
Embryonic Stage correct answersstarts on day 15 (after pre-stage) and lasts until approx. 8 weeks
after conception.
Most critical time in development of the organ system and external features: correct answersthe
EMBRYONIC STAGE (first 8 weeks)
The time when embryos are most vulnerable to teratogens: correct answersthe EMBRYONIC
STAGE
Chorion correct answers-outermost embryonic membrane that encircles the amnion, embryo, and
yolk sac
-*thickest* membrane that develops from the trophoblast
-has appendages called chorionic villi
-the chorion begins to degenerate after approx. 10th week to be smooth by the 4th month
Genetic sampling used for what and when can it be done: correct answersused from the chorionic
villi and can only be done up to the 10th week. tests for down syndrome.
Amnion correct answers-second embryonic membrane to form, originating from the ectoderm
-thin protective membrane that contains amniotic fluid
-amnion expands with embryo growth until it comes into contact with the chorion
Embryonic Cavity correct answersspace between the amniotic membrane and the embryo
BOW (bag of waters) correct answers-formed by the two adherent membranes (chorion and
amnion).
-the membrane containing the amniotic fluid and the fetus
-provides fluid to protect the floating embryo.
Amniotic Fluid correct answers-prevents adherence of the embryo to the amnion wall to allow
freedom of movement so that the embryo can change position, thus aiding in musculoskeletal
development
-functions as a cushion to protect against injury
1) ||Completely solved.
Conception correct answersthe union of a single egg and sperm
Meiosis correct answersthe process of cell division that occurs in the maturation of sperm and
ova that decreases their # of chromosomes by one-half. (from 46 chromosomes to 23). Occurs
during gametogenesis.
Zygote correct answersformed from the male gamete when united with the female gamete.
When ova is considered fertile: correct answers24 hours after ovulation.
How long can sperm survive: correct answersit can survive in the reproductive tract for 48-72
hours.
Process of fertilization: correct answerswhen a sperm fuses with an ovum to form a new diploid
cell or zygote.
High estrogen levels during fertilization: correct answershigh estrogen levels increase peristalsis
within the fallopian tube helping to move the ovum through the tube to the uterus for
implantation in the endometrium.
Intrauterine Development correct answers-the zygote begins cellular multiplication in the
fallopian tube
-changes from blastomeres to the morula
-blastocyst and trophoblast are formed
Trophoblast correct answerseventually develops into the chorion.
Blastocysts correct answerseventually develops into embryo and the amnion.
Implantation (Nidation): correct answers-where the trophoblast attaches to the surface of the
endometrium
-cells of the trophoblast grow into the thickened lining forming villi
-implantation is completed by the 9th day.
Most frequent site of implantation: correct answersupper part of the posterior uterine wall
Progesterone during implantation: correct answersincreases the endometrial thickness and
vascularity in preparation for implantation.
3rd week AFTER conception correct answersthe primary germ layers form.
Time frame of fertilization: correct answers2-3 days
, Time frame of completed implantation: correct answers9th day from conception.
Ectoderm correct answersepidermis, the glands, the nails & hair, CNS/PNS, pituitary glands,
mammary glands
Mesoderm correct answersbones, teeth, muscles, dermis, wall of digestive tract, cardiovascular
system, lymphatic tissue and cells, pleura, spleen
Endoderm correct answersepithelial lining of the respiratory & GI tract, Vagina (parts), urinary
bladder, urethra, epithelium
Embryonic Stage correct answersstarts on day 15 (after pre-stage) and lasts until approx. 8 weeks
after conception.
Most critical time in development of the organ system and external features: correct answersthe
EMBRYONIC STAGE (first 8 weeks)
The time when embryos are most vulnerable to teratogens: correct answersthe EMBRYONIC
STAGE
Chorion correct answers-outermost embryonic membrane that encircles the amnion, embryo, and
yolk sac
-*thickest* membrane that develops from the trophoblast
-has appendages called chorionic villi
-the chorion begins to degenerate after approx. 10th week to be smooth by the 4th month
Genetic sampling used for what and when can it be done: correct answersused from the chorionic
villi and can only be done up to the 10th week. tests for down syndrome.
Amnion correct answers-second embryonic membrane to form, originating from the ectoderm
-thin protective membrane that contains amniotic fluid
-amnion expands with embryo growth until it comes into contact with the chorion
Embryonic Cavity correct answersspace between the amniotic membrane and the embryo
BOW (bag of waters) correct answers-formed by the two adherent membranes (chorion and
amnion).
-the membrane containing the amniotic fluid and the fetus
-provides fluid to protect the floating embryo.
Amniotic Fluid correct answers-prevents adherence of the embryo to the amnion wall to allow
freedom of movement so that the embryo can change position, thus aiding in musculoskeletal
development
-functions as a cushion to protect against injury
