Specialized Root Function

Question 1

root specialization: asexual reproduction

Answer 1

• roots form adventitious buds, from these aerial stems (suckers) form; suckers develop their own roots and can survive independently
• common strategy in shrubs and fruit trees

Question 2

root specialization: gas exchange

Answer 2

plants growing near water or swamps can have pneumatophores that extend above surface and use lenticels to obtain oxygen

Question 3

root specialization: aerial roots

Answer 3

• epiphytes such as orchids grow on other plants for support but nourish themselves (not parasite)
• velamen layer: epidermis several cell layers thick to reduce water loss
• epiphyte roots absorb water and nutrients from rain
• aerial roots can also aide in climbing

Question 4

root specialization: aerial (prop) roots

Answer 4

• tropical trees have stilt-like prop roots that grow down from branches
• once reach ground, continue secondary growth to expand radius and stability

Question 5

root specialization: additional support

Answer 5

buttress roots extend from base of tree trunks to help stabilize tree in shallow soil; common in tropical trees

Question 6

root specialization: parasitism

Answer 6

• parasitic roots (dodders) have no chlorophyll and depend on chlorophyll-bearing plants for nutrition
• dodders use peg-like projections (haustoria) to tap into vascular system of host plant
• not beneficial to host