Prenatal Period (Conception to Birth) Flashcards
(35 cards)
What are the three main periods of prenatal development?
Stage 1: Germinal
Stage 2 Embryonic
Stage 3: Fetal.
What key event marks the beginning of the germinal period?
Fertilization
What is the blastocyst and what happens to it during the germinal period?
A hollow ball of cells that prepares for implantation in the uterus. The blastocyst contains an inner cell mass (which will become the embryo) and an outer cell mass (which will form the placenta).
What is the main developmental focus of the period of the embryo (weeks 2-8)?
The foundations for all body structures and organs are laid down.
What important structure forms during the period of the embryo that develops into the brain and spinal cord?
The neural tube.
What is the primary characteristic of development during the period of the fetus (week 9 - birth)?
Touch
What is the primary characteristic of development during the period of the fetus (week 9 - birth)?
Dramatic increase in body size and completion of physical structures.
What is the “age of viability” for a fetus?
Around 22-26 weeks, when the fetus has a chance of surviving outside the womb with medical help.
What is a teratogen?
Any environmental agent that can cause damage during prenatal development.
During which period of prenatal development is the developing organism most vulnerable to the effects of teratogens causing major structural damage?
The embryonic period (weeks 2-8).
Give an example of a potent teratogen commonly used to treat severe acne.
Accutane
What are some potential risks for babies born to mothers who use cocaine, heroin, or methadone?
Prematurity, low birth weight, brain abnormalities, physical defects, breathing difficulties, and infant death.
What are gametes?
Specialized reproductive cells (sperm and egg) that carry half the genetic material necessary for reproduction.
What determines biological sex in humans?
The combination of sex chromosomes: XX for females and XY for males.
Name 3 types of fertility treatments
IVF, Surrogacy, Artifical Insemination
Differentiate between meiosis and mitosis
The purpose of mitosis is cell regeneration, growth, and asexual reproduction,while the purpose of meiosis is the production of gametes for sexual reproduction. Meiosis is a type of cell division that produces gametes (sperm and egg cells)while, Mitosis is a where a single cell divides to produce two genetically identical daughter cells.
What is Sickle Cell Disease & Tay-Sachs Disease?
Sickle cell disease is a hereditary blood disorder where red blood cells assume a sickle shape, leading to various complications. While Tay Sachs is a genetic disorder that destroys nerve cells in the brain and spinal cord, typically fatal in early childhood.
Why is genetic counseling recommended for prospective parents?
To assess the risk of inherited disorders and discuss reproductive options.
What are common causes of infertility?
Low sperm count, cancer treatments like chemotherapy, sexually transmitted diseases (STDs), and genetic incompatibilities.
What is IVF (In-vitro fertillization)
A process where eggs are fertilized by sperm outside the body and then implanted into the uterus.
What is an ultrasound?
A non-invasive imaging technique using high-frequency sound waves to visualize the fetus, assess growth, and detect abnormalities.
Name 2 types of prenatal diagnostic techniques and tell me what they do?
CVS is a test where a small sample of placental tissue is taken to detect genetic disorders, usually performed early in pregnancy and Amniocentesis is a procedure where amniotic fluid is extracted to test for genetic conditions, typically done around 14 weeks of gestation.
When is the fetus most vulnerable to teratogens?
During the first trimester, especially between the 3rd and 8th weeks of development
What triggers the onset of labour?
The release of oxytocin from the pituitary gland, leading to uterine contractions.
