Developmental Anomalies (Ex3)

Question 1

What are the types of anatomic defects?

Answer 1

• failure to fuse
• failure to canalize/separate
• cysts
• failure of a structure to develop
• abnormal development of a structure
• ectopic development

Question 2

Explain the pathogenesis of arthrogryposis

Answer 2

• limbs do not move during development
• muscles don’t develop correctly
• connective tissue matures
• limbs are fixed in place

Question 3

What is hydraencephaly?

Answer 3

• cerebral hemispheres have not developed

- affected calves called dumby cows

Question 4

What are the four main causes of developmental anomalies?

Answer 4

• genetic defect
• in-utero infection
• in-utero exposure to teratogens
• in-utero nutritional deficiencies

Question 5

What is palatoschisis?

What is the etiology?

Answer 5

• failure of the roof of the mouth to fuse
• cleft palate
• Griseofulvin (teratogen)

Question 6

What is synophthalmia?

What is the etiology?

Answer 6

failure of the orbit to separate

- ingestion of veratrum californicum at day 14 of gestation

Question 7

Define aplasia

Answer 7

failure to develop

Question 8

What are the 4 genetic etiologies of developmental anomalies?

Answer 8

• inherited genes: often autosomal recessive
• spontaneous somatic genetic defect
• chromosomal anomalies
• breed dispositions

Question 9

What is spina bifida?

Answer 9

cleft in the dorsal tissues of the spine

Question 10

What is cheiloschisis?

Answer 10

cleft lip

Question 11

What is hypospadias?

Answer 11

cleft in the penis, exposing the urethra

Question 12

What is coloboma?

Answer 12

cleft in the internal structures of the eye

Question 13

What is intraventricular cardiac septal defect?

Answer 13

a hole communicating between the ventricles of the heart

Question 14

What is meningeoencephalocele?

Answer 14

failure to fuse of the skull

Question 15

Define atresia

Answer 15

failure to canalize

Question 16

What is polydactyly?

Answer 16

too many digits

Question 17

What is polymelia?

Answer 17

too many limbs

Question 18

Describe biochemical defects

Answer 18

• involve an inability to synthesize adequate amounts of a particular enzyme or other protein
• usually no grossly visible malformations
• usually due to genetic mutation

Question 19

What is mannosidosis?

Answer 19

• vacuolar neuronal degeneration
• due to genetic defect for mannosidase
• mannis accumulates in cytoplasm, so neurons unable to function normally

Question 20

What are lysosomal storage disease?
How do they appear histologically?
What cells are most susceptible?

Answer 20

• genetic deficiency of particular lysosomal enzymes
• histo: vacuoles filled with the accumulated substrate of the deficient enzyme
• post-miotic cells most susceptible: neurons, skeletal and cardiac muscle

Question 21

What is Neiman Pick disease?

Answer 21

• vacuolar neuronal degeneration

- genetic defect for sphingomyelinase