Ulva lactuca (sea lettuce) is a multicellular green alga that lives attached to rocks in marine intertidal zones. Unlike terrestrial plants, Ulva lactuca completely lacks vascular tissues such as xylem.
Suggest how Ulva lactuca is able to transport substances and survive in its marine habitat without xylem tissue.
Ulva lactuca has both multicellular haploid and diploid forms that look morphologically identical.
Figure 1 shows the simplified life cycle of Ulva lactuca.
Identify the type of cell division happening at each stage. Complete each box with the appropriate letter: use 'T' for mitosis and 'E' for meiosis.
Ulva reticulata is another species of green alga that releases flagellated haploid gametes into the same coastal environment.
Suggest and explain one reason why successful reproduction between Ulva lactuca and Ulva reticulata to produce fertile offspring does not happen.
Practise AQA A Level Biology Species and taxonomy with exam-style questions for A Level Biology. 12 questions, matched to the AQA A Level Biology (7402) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
