Lecture 28 - Overview of Congenital Malformations Flashcards
(14 cards)
A ___________ is an abnormality of structure that results from an abnormally functioning tissue (e.g. incomplete growth, duplication).
A. Syndrome B. Malformation C. Mutation D. Deformation E. Disruption
B.
Two examples of malformation abnormalities include:
- incomplete growth
2. duplication
In a __________, tissue formation is normal but abnormalities result from extrinsic causes that do not lead to tissue breakdown and loss.
A. Syndrome B. Malformation C. Mutation D. Deformation E. Disruption
D.
Note: Disruptions are also defined this way, except they DO lead to tissue loss. (They are more severe)
In a __________, tissue formation is normal but abnormalities result from extrinsic causes that lead to severe tissue breakdown and loss.
A. Syndrome B. Malformation C. Mutation D. Deformation E. Disruption
E
A sequence is a type of multiple malformation. How is it defined?
malformations linked to a single initiating event
An __________ refers to malformations that occur together in a nonrandom manner.
association
A syndrome is a complex of malformations having one of two general traits. What are these traits?
- has a defined genetic cause
2. has a defined environmental insult
What are the three types of ‘multiple malformations’?
- Syndrome
- Association
- Sequence
Causes of malformations encompass 5 major categories, including:
- Abnormal chromosome structure or number
- Single gene mutation
- Multifactorial-complex disorders
- Unknown origin (*note: 50% of malformations arise from unknown origin)
- Environmental agent
What is a critical period?
the period of maximum susceptibility to factors causing abnormal development
The critical period of each organ is different, and linked to that organ’s:
time of formation
What are two reasons that abnormalities prior to 3 weeks of development are not generally associated with congenital defects?
- early embryo may be able to correct for damage
2. early embryo may not survive at all
The most common congenital malformations are:
heart defects
A syndrome is distinguished from an association by the fact that:
a syndrome is associated with a KNOWN mutation, chromosomal abnormality, or environmental insult
