Embryology Flashcards
Recall the 4 cellular processes at work in embryological development
Proliferation
Differentiation
Reorganisation
Apoptosis
Recall the 3 stages of renal development in utero
Pronephros
Mesonephros
Metanephros
Describe the location of kidneys as they develop
Ascend into the abdomen as they develop
What is significant about the mesonephros pre-kidney structure?
This is where the mesonephric and paramesonephric ducts develop, that will eventually differentiate into the genital ducts
Describe the arterial supply to the kidneys during embryonic development
Has to form and degenerate and reform as kidneys develop as they move up abdomen
Where do the gonads originate from embryologically?
Intermediate mesdoerm
What are the mesonephric and paramesonephric ducts?
Mesonephric = future wolffian ducts Paramesonephric = future uterine tubes, uterus and cervix
At which week of development do the reproductive systems of male and female embryos begin to differ?
8/9
Recall the 2 hormones that are produced in the presence of the SRY gene
DHT
Anti-mullerian hormone
What is the developmental function of DHT?
Supports development of Wolffian ducts
What is the Wolffian duct?
Duct that gives rise to male reproductive tract
Where is anti-Mullerian hormone produced?
Sertoli cells
What is the developmental function of anti-mullerian hormone?
Causes regression of paramesonephric ducts
Where does heart development begin?
Outside the embryo proper
Describe the first 21 days of heart development
First 2 tubes are formed, these fuse at day 21 to produce a single tube which can pump blood unidirectionally
Where is the foramen ovale located?
Between atria
What does the foramen ovale bypass in the foetus?
Right ventricle + therefore pulmonary circulation
Where is the ductus arteriosus located?
Right ventricle and aorta
What is the Tetralogy of Fallot?
Aorta and RV connected causing transposition of vessels
Recall 3 features of the tetralogy of fallot?
- Pulmonary stenosis
- RV thickening
- Ventricular septal defect
Recall the 5 stages of lung development
Embryonic Pseudoglandular Cannalicular Saccular Alveolar
In which trimester is surfactant produced and why is this significant?
3rd
Prem babies have lung problems
What is a genetic mosaicism?
Meiotic non-disjunction causing different cells within the body to have non-identical genetic makeup
What is the most likely cause of spina bifida?
Folic acid deficiency
Recall 3 severities of spina bifida
Only a spot of hair seen = SB occulta
Slight herniation = meningocele
Significant protrusion of meninges = myelomeningocele
When does the malformation occur in spina bifida and what is the problem?
Around 4 weeks
Faulty neuralation
What is a cleft palate?
Connection between the mouth and nasal cavity
Recall 4 infectious agents that are common teratogens
Rubella
Syphilllis
HIV
HSV
Summarise how illicit drug use can affect the embryo
Addiction once baby is born SIDS Seizures Respiratory problems Mental retardation Pre-term deliver risk LBW Learning difficulties
Recall 3 symptoms of foetal alcohol syndrome
Distinctive facial features
Brain abnormalities
Cognitive defects
