Biotic interactions

Question 1

What caused potato famine

Answer 1

lack of genetic variability by monoculture and the oomycete

Question 2

What was the Dutch elm disease

Answer 2

devastating disease that almost eliminated elm trees in America and Europe. Caused by pathogenic fungi which is spread by elm bark beetles. Elm trees plug its own xylem tissue but that leads to failure of xylem function.

Question 3

What are the three types of insect attacks

Answer 3

1) Phloem feeders
2) Cell-content feeder
3) Chewing insects

Question 4

What is volicitin? Where is it found?

What is it made of?

Answer 4

Volicitin is an elicitor
It is made from fatty acid and amino acid conjugate
It can be found in the larvae of the beet armyworm

Question 5

What are the two steps of the insect elicitor signaling pathway?

Answer 5

1) cytosolic calcium concentration increases. Calcium is used as a secondary messenger
2) Octadecanoid pathway is activated to synthesize jasmonic acid, which in turn activates a wide array of defense responses.

Question 6

Jasmonic acid is similar to what molecule in humans?

Answer 6

Prostaglandin

Question 7

What are the three anti-digestive proteins initiated by JA and what are their functions?

Answer 7

alpha-amylase inhibitors - inactivate amylase

Lectin - interfere with protein absorption

Proteinase inhibitor - tightly bind to key protein hydrolyzing enzymes (trypsin and chymotrypsin)