9.8 XYLEM, PHLOEM, AND PLANT PESTS

Question 1

What is the transportation of glucose in plants?

Answer 1

1. Glucose is produced by photosynthesis
2. Glucose is dissolved in water and transported to parts of plant through phloem
3. Transportation of glucose requires energy

Question 2

What is the adaptation of phloem?

Answer 2

1. Phloem allows bidirectional movement of solutes
2. Composed of sieve element cells which connect to form a tube
3. Supported by companion cells that help with loading/unloading

Question 3

What are the differences between xylem and phloem?

Answer 3

1. Phloem is a living tissue which uses energy to move glucose around the plant
2. Xylem is a dead tissue, made up of tubes that carry water from roots to the leaves

Question 4

What are insect pests and what are their speciality?

Answer 4

1. Insects the target sugar-rich phloem tubes for food
2. Specialised mouth part called stylets
3. Stylets are sharp, pointed, hollow tubes

Question 5

What are the impacts of pests in plants?

Answer 5

1. Weaken plants
2. Reduce crop yields
3. Carries pathogen to plants’ transport system through their stylets when feeding
4. Pathogens blocked xylem tissue, water cannot reach stems & leaves, plant dies