chromosomal abnormalities

Question 1

numerical abnormalities

Answer 1

aneuploidy and polyploidy

Question 2

what is aneuploidy?

Answer 2

abnormalities in meiosis, missing a chromosome from pair or has extra chromosome in pair

Question 3

trisomy

Answer 3

extra chromosome in pair, eg down syndrome trisomy 21

Question 4

monosomy

Answer 4

turner syndrome - female born with 1 X

Question 5

what is polyploidy

Answer 5

more than 2 pairs of the same chromosome

Question 6

structural abnormalities

Answer 6

ring formation, deletions, duplications, inversion, translocation

Question 7

What are deletions

Answer 7

portion of chromosome is missing, terminal or interstitial

Question 8

consequences of deletions

Answer 8

unmasking of mutant alleles and insufficient gene products eg cri de chat syndrome

Question 9

what are inversions

Answer 9

portion broken off , turner upside down and re attached, can be pericentric or paracentric

Question 10

what causes epilepsy

Answer 10

ring formation abnormality

Question 11

translocations

Answer 11

portions of chromosome transferred to another

Question 12

what is robertsonian translocations

Answer 12

entire chromosome attached to another at centromere

Question 13

what causes schizophrenia

Answer 13

translocation

Question 14

how does mosaicism occur?

Answer 14

abnormality occurs after conception