Fetal Development and Genetics

Flashcards about fetal development and genetics.

What occurs during the preembryonic stage of fetal development?

Fertilization through the second week, involving fertilization, cleavage, morula, blastocyst, trophoblast, and implantation.

What occurs during the embryonic stage?

From the end of the second week through the eighth week, during which basic structures of major body organs and main external features develop.

What occurs during the fetal stage?

From the end of the eighth week until birth.

What does the ectoderm layer form?

Forms the central nervous system, special senses, skin, and glands.

What does the mesoderm layer form?

Forms skeletal, urinary, circulatory, and reproductive organs.

What does the endoderm layer form?

Forms the respiratory system, liver, pancreas, and digestive system.

What are the functions of the placenta?

Interface between the pregnant person and fetus, makes hormones, protects the fetus from immune attack, removes waste products, induces the patient to bring more food, and produces hormones for fetal organ maturation.

What does hCG stand for?

Human chorionic gonadotropin.

What does hPL stand for?

Human placental lactogen or human chorionic somatomammotropin.

What are the characteristics of the umbilical cord?

Formed from the amnion, lifeline from the pregnant person to the growing embryo, contains one large vein and two small arteries, surrounded by Wharton jelly to prevent compression.

What is the role of amniotic fluid?

Maintains constant body temperature, permits symmetric growth and development, cushions the fetus from trauma, allows the umbilical cord to be free of compression, and promotes fetal movement.

What does the ductus venosus do?

Connects the umbilical vein to the inferior vena cava.

What does the ductus arteriosus do?

Connects the main pulmonary artery to the aorta.

What is the foramen ovale?

Anatomic opening between the right and left atrium.

What is genetics?

Study of heredity and its variation.

What is pharmacogenomics?

Study of genetic and genomic influences on pharmacodynamics and pharmacotherapeutics.

What was the goal of the Human Genome Project?

Map, sequence, and determine the function of all human genes.

What is a genotype?

Genes inherited from parents.

What is a phenotype?

Observed outward characteristics.

What is a karyotype?

Pictorial analysis of number, form, and size of chromosomes.

What are genes?

Individual units of heredity of all traits.

What are abnormalities of chromosome number?

Monosomies, trisomies, and polyploidy.

What are abnormalities of chromosome structure?

Deletions, inversions, and translocations.

What are examples of structural chromosomal abnormalities?

Cri du chat syndrome and Fragile X syndrome.

What are examples of sex chromosome abnormalities?

Turner syndrome and Klinefelter syndrome.

What does genetic evaluation and counseling involve?

Ideal time is before conception; involves advising patients or relatives at risk of an inherited disorder.