Biology: Translocation

Question 1

What vessel is involved with translocation?

Answer 1

phloem

Question 2

Outline the structure of the phloem

Answer 2

consist of sieve tube elements and companion cells

Question 3

How are sieve tube elements structured, state the function for each of these traits

Answer 3

-living cells
-perforated walls: continuous flow
-contain no nucleus: maximum flow
-contain few organelles: maximum flow

Question 4

What is the role of the companion cells?

Answer 4

provide ATP required for active transport

Question 5

What is translocation?

Answer 5

process by which products of photosynthesis are transported from a source to a sink

Question 6

What is a source cell?

Answer 6

cell in which the products of photosynthesis especially sucrose/glucose are made

Question 7

What is a sink cell?

Answer 7

cell in which the products of photosynthesis are used

Question 8

How is a difference in pressure established for translocation?

Answer 8

-photosynthesis forms soluble sugars, lowers water potential, water enters via osmosis, hydrostatic pressure increases
-sink cell uses sucrose/sugar, more positive water potential, water leaves via osmosis, hydrostatic pressure decreases
-source cell has high hydrostatic pressure, solution forced to sink cell via phloem