Chromosomal Abnormalities

Question 1

What is euploidy?

Answer 1

entire haploid chromosomal sets lost/added

Question 2

What is aneuploidy?

Answer 2

individual chromosomes lost/added

Question 3

What are the effects of monoploidy?

Answer 3

• sterile

- typically do not develop due to allele unmasking

Question 4

What does colchicine do?

Answer 4

prevents microtubules from forming in meiosis

Question 5

What are the effects of tetraploidy?

Answer 5

• fertile

- larger yields

Question 6

What is allopolyploidy?

Answer 6

combining two separate chromosome sets from different species, which doubles the chromosome count

Question 7

How do you make a triploid?

Answer 7

• expose diploid to colchicine, making it tetraploid

- cross tetraploid with diploid to create triploid

Question 8

What are the effects of triploidy?

Answer 8

• sterile (seedless)

- higher yields

Question 9

What gametes are produced during a single CO with pericentric inversion?

Answer 9

• 2 viable gametes (one identical to parent, one with functional inversion)
• 2 inviable gametes (missing key genes)

Question 10

What are the effects of deletion?

Answer 10

• overproduction of protein (attached to strong promoter instead of weak)
• creation of new protein
• underproduction of functional RNA (attached to weak promoter instead of strong)
• spontaneous abortion

Question 11

What are the effects of duplication?

Answer 11

• gene families evolve
• produces different phenotypes due to gene imbalance
• can produce genes when needed

Question 12

What are the effects of inversion?

Answer 12

• 50/50 chance of viable offspring

Question 13

What are the effects of translocation

Answer 13

• chromosomes can get lost if they are too small

Question 14

What is Robertsonian translocation?

Answer 14

• when the majority of one chromosome is attached to tip of another chromosome
• causes trisomy 21

Question 15

What is reciprocal translocation?

Answer 15

DNA is swapped and nothing is lost