BIOLOGY 366 PLANT SYSTEMATICS EXAM POINTS TOTAL (LECTURE 100, LAB PRACTICAL 50)

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1 BIOLOGY 366 PLANT SYSTEMATICS EXAM POINTS TOTAL (LECTURE 100, LAB PRACTICAL 50) SECTION 1 (Short answer; 80 points total): Be as precise as possible in your answers. 1. What makes the alternation of generations life cycle different from the other two types of life cycle found in eukaryotes? (10 points) 2. (A) Name three features that all land plants (embryophytes) share. (B) Name one feature that embryophytes share with the green algae. (10 points) Page 1

2 3. Stems and leaves sometimes are shaped by evolution to acquire novel appearances and/or functions. (A) Define two specialized stem types and two specialized leaf types. (B) Describe how you might determine whether a particular part is homologous to a leaf or a stem. (18 points) 4. Describe the evolution of the angiosperm compound ovary from an ancestral preangiosperm with megasporophylls bearing marginal ovules. Your answer must include clear definitions of and distinctions between these terms: megasporophyll, carpel, locule, ovary, gynoecium, septum, ovule, and placentation. (26 points) Page 2

3 6. Cladistic analysis (23 points total): The genus Yura contains 5 species (Y. messa, Y. obnoxia, Y. beatifica, Y. confusa, Y. foetida). All of them share many character states that distinguish this genus from all closely related genera. The species differ from each other, however, as described below. All species in the most closely related genus, Ima, are upright plants with simple leaves, and have sweet-smelling flowers with large, red, free petals and 10 stamens; fruits in Ima are capsules. Yura messa: Plant upright; leaves simple; petals white, connate; stamens 5; flowers Yura obnoxia: Plant upright; leaves pinnately compound; petals red, free; stamens 10; flowers with a rotten meat smell; fruit a berry. Yura beatifica: Plant vining; leaves simple; petals white, free; stamens 10; flowers Yura confusa: Plant upright; leaves simple; petals white, connate; stamens 10; flowers Yura foetida: Plant vining; leaves pinnately compound; petals red, free; stamens 10; flowers with a rotten meat smell; fruit a berry. Study the data matrix below, in which characters are coded according to whether character states are plesiomorphic (0) or apomorphic (1). Character/ Species Habit Leaves Petal Color Petal fusion Stamen number Flower odor Fruit type Y. messa Y. obnoxia Y. beatifica Y. confusa Y. foetida Outgroup Construct a cladogram from the data matrix. Indicate the evolution of all seven characters on the tree (that is, show all synapomorphies and any autapomorphies or homoplasy) as hash marks labeled with the appropriate character state. (10 points) Page 3

4 Which character state supports the monophyly of Yura in this analysis? (2 points) Which character state is autapomorphic, and for which species? (2 points) Which character state appears to have arisen independently two times, and in which species? (2 points) SECTION 2 (True/False; 2 points each, 20 points total): If a statement is true, mark a T next to it. If the statement is false, mark an F next to it and then indicate how you would correct it to make it true, as in the example below. Note that simply inserting or deleting the word not is not sufficient to correct a false statement. Example: The Earth is flat. 1. The sepals in an individual flower are collectively known as the corolla. 2. A complete flower must be a perfect flower. 3. Vascular plants (tracheophytes) are an example of a paraphyletic group. 4. The pericarp of a fruit is derived from the ovary wall. 5. A monophyletic group includes a common ancestor and all of its descendents. 6. If the cells of a fern frond each contain 50 chromosomes, then the cells of its gametophyte will each contain 50 chromosomes. 7. Bryophytes had to stay small so that their sperm could swim to their eggs for fertilization. 8. The hypanthium is the floral axis that bears all of the flower parts. 9. Of the major groups of plants, gymnosperms have the greatest number of species. 10. Capsules are a type of dehiscent fruit derived from two or more carpels. Page 4

5 SECTION 3: LABORATORY PRACTICAL (50 PTS) Name: Page 5