Use your knowledge of indoleacetic acid (IAA) to explain the growth curvature shown in Figure 1 - AQA - A-Level Biology - Question 3 - 2021 - Paper 2
Question 3
Use your knowledge of indoleacetic acid (IAA) to explain the growth curvature shown in Figure 1.
Figure 1 shows an investigation into growth factors in plants.
Tip... show full transcript
Worked Solution & Example Answer:Use your knowledge of indoleacetic acid (IAA) to explain the growth curvature shown in Figure 1 - AQA - A-Level Biology - Question 3 - 2021 - Paper 2
Step 1
Tip produces IAA
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The tip of the plant produces indoleacetic acid (IAA), which is essential for plant growth.
Step 2
IAA diffuses into shoot
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
IAA produced in the shoot tip diffuses down the plant stem, promoting elongation of the cells.
Step 3
Elongation of cells on one side
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
When the tip is placed on one side of the cut shoot, more IAA accumulates on that side which causes the cells on that side to elongate more than those on the opposite side, resulting in growth curvature toward the side opposite to where the IAA diffused.