6.1 Chromosomal Mutations

Question 1

What are chromosomal mutations also known as?

Answer 1

aberrations

Question 2

What are chromosomal mutations?

Answer 2

alterations to the chromosome including increases or decreases in total number, deletions or additions to segments, or complete rearrangments

Question 3

How are chromosomes arranged?

Answer 3

in sets

Question 4

What is aneuploidy?

Answer 4

addition or loss of one autosomal chromosome but NOT the set

Question 5

What is the loss of a single chromosome referred to as?

Answer 5

monosomy (2n-1)

Question 6

What is the gain of a single chromosome referred to as?

Answer 6

trisomy (2n+1)

Question 7

What are the most common examples of aneuploidy?

Answer 7

monosomy and trisomy

Question 8

What results from monosomy in the X chromosome?

Answer 8

developmental and health problems but NOT lethal

Question 9

What results from monosomy in autosomal cells?

Answer 9

lethal

Question 10

Where is monosomy more tolerated?

Answer 10

in plant kingdom

Question 11

Which is more tolerated in animals: monosomy or trisomy?

Answer 11

trisomy

Question 12

What is the general rule of trisomy in an animal and its lethality?

Answer 12

the smaller the chromosome the less lethal

Question 13

What does trisomy usually change in plants?

Answer 13

phenotype

Question 14

What is trisomy 21 known as?

Answer 14

down syndrome

Question 15

What is the only human trisomy in which individuals routinely live longer than a year?

Answer 15

down syndrome

Question 16

Who first discovered trisomy 21 and when?

Answer 16

Langdon Down in 1866

Question 17

What is the prevalance of down syndrome in children?

Answer 17

1 in 700

Question 18

What is the average lifespan of an individual with down syndrome?

Answer 18

50 years

Question 19

What increases the risk of having a child with down syndrome?

Answer 19

increased maternal age

Question 20

What is usually the cause of death in an individual with down syndrome?

Answer 20

alzheimers