Figure 18 shows the leaves and flowers of water lily plants (Nymphaea odorata) on a lake - Edexcel - GCSE Biology - Question 8 - 2020 - Paper 1
Question 8
Figure 18 shows the leaves and flowers of water lily plants (Nymphaea odorata) on a lake.
(a) Water lilies have stomata on the upper surface of the leaves.
Explain ... show full transcript
Worked Solution & Example Answer:Figure 18 shows the leaves and flowers of water lily plants (Nymphaea odorata) on a lake - Edexcel - GCSE Biology - Question 8 - 2020 - Paper 1
Step 1
Explain why water lilies have no stomata on the lower surface of the leaves.
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 lower surface of the water lily leaf is submerged under water, meaning it is not in contact with air. Therefore, gas exchange cannot occur, as there is no need for stomata on the lower side.
Step 2
Which structure in leaf cells is the site of photosynthesis?
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
The site of photosynthesis in leaf cells is the D chloroplast.
Step 3
What is the name of this sugar?
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
The name of this sugar is C sucrose.
Step 4
Describe how this sugar is transported from the leaves to the flowers of the water lily.
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The sugar, sucrose, is transported through the plant via the phloem in a process known as translocation. This occurs when the sugar is dissolved in water and moved from areas of high concentration in the leaves to areas of lower concentration in the flowers.
Step 5
Explain why this non-indigenous plant now covers the whole surface of the lake.
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The non-indigenous water lily has likely thrived due to favorable conditions such as abundant sunlight and suitable growth conditions in the lake. As it adapted well to the ecosystem, it outcompeted native plants for resources, allowing it to grow and reproduce rapidly. Furthermore, the absence of natural herbivores that would eat or restrict its growth contributed to its dominance in the lake.
Step 6
Explain how the water lilies will affect the biodiversity of this lake.
97%
121 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The presence of water lilies can reduce biodiversity by decreasing the variety of plant and animal life in the lake. This is because the water lilies may overshadow other plants, leading to fewer species overall. Additionally, with less light reaching the water due to the coverage, fewer plants can photosynthesize, affecting the food chain and oxygen levels, which in turn impacts animal populations.