Chapter 1 Flashcards
The blastocyst stage of the human embryo
Is the stage at which implantation begins
Which of the following describes the number of chromosomes and amount of DNA in a gamete?
23 Chromosomes, 1N
A young couple hoping for a pregnancy buys an over the counter pregnancy kit. What substance will this test most likely detest?
Human chorionic gonadotropin
hCH
From which primary germ layer is the epidermis of the skin derived?
Ectoderm
The notochord forms the initial axial skeletal element of the body and induces the formation of the neural plate. Which of the following structures is the only post-natal remnant of the embryonic notochord?
Nucleus pulposus of intervetrebral disc
The syncytiotrophobast
Arises from cytotrophoblast
An infant is born with sacrococcygeal teratoma. Biopsy and histologic analysis reveal that it contains intestinal epithelia, cardiac muscle, cartilage and integument tissue. You counsel the mother that the tumor is benign and recommend surgical removal. This tumor was caused by which developmental anomaly?
Failure of primitive streak regression
The chorionic cavity is lined with which of the following?
Extrembryonic mesoderm
Parents bring their 3 year old son to your clinic for evaluation. They complain that, unlike his older sister, his teeth look ‘funny’, some are missing and his hair is very thin. He doesn’t sweat and they have trouble regulating his temperature. He also has vision and hearing problems. This child’s anomalies are related to defects in
Epithelial ectoderm
Which germ layers are present by the end of week three of development
Ectoderm, mesoderm, and endoderm
