Parasitism in Plants

Question 1

Holoparasites

Answer 1

Parasites with no chlorophyll that cannot photosynthesise and are therefore dependant on their host for for all food.

Question 2

Hemiparasites

Answer 2

Parasites that have chlorophyll that can photosynthesise and are therefore only partially dependant on their host for food.

Question 3

Dodder

Answer 3

Holoparasite that lives on a variety of plants including agricultural plants, causing extensive damage leading to great economic loss

Question 4

Structure of Dodder plants

Answer 4

Long, thin, yellow stem

Tiny seeds produced in great quantities

Question 5

Process of finding and attaching to a host

Answer 5

Survival period without a host: 5-10 days after germination
Stem performs swaying movements, coiling around the host plant
Haustoria (sucking roots) penetrate through vascular tissue to extract water, mineral salts and organic nutrients
After establishment, origional root dies
stem grows and forms branches and spread to other plants

Question 6

What happens to the host?

Answer 6

Host weakened and disadvantaged