What are homeotic genes?  Please exaplain ow they control the sequence of whorl development in flowers according to the ABCDE model.

Describe natural and artificial methods of asexual reproduction in plants.

Explain the sequence of events in a flowering plant that begins with formation of a pollen tube and culminates with the formation of a diploid zygote and the 3n cell that will give rise to endosperm in a seed.

Choose the statement that is true. a. All flowers are pollinated by bees. b. Apple trees are propagated by grafting because they are triploid. c. Carpels function to attract pollinators. d. A coleoptile protects the plumule of eudicot seedlings. e. The arrival of pollen on a receptive seed is called pollination. f. In plants, sperm cells are male gametes. g. Nutrients in fruits nourish new seedlings.

A scientist pollinates a true-breeding pea plant with violet, terminal flowers with pollen from a true- breeding pea plant with white, axial flowers. Which of the following observations would most accurately describe the F2 generation? 75% violet flowers; 75% terminal flowers 75% white flowers in a terminal position 75% violet flowers; 75% axial flowers 75% violet flowers in an axial position

15. The sticky cinquefoil (Potentilla glandulosa) is a small, deciduous plant with bright yellow flowers that lives throughout the American West, and its leaf phenotype can vary depending on environmental conditions. Inland, where there are dramatic seasonal temperature swings and unpredictable droughts, plants shed their large “summer leaves” in autumn when the temperature begins to drop. In the spring new leaves are smaller and develop in a compact rosette. This phenotype persists for several months and is thought to be an adaptation that makes the plants drought-resistant (because less water evaporates from reduced leaf surfaces). By contrast, the leaves of P. glandulosa plants growing in a coastal climate are always large. In their habitat, seasonal temperature swings are not as great and the annual cycle of winter rain and summer drought is highly predictable. Suppose you decide to explore the hypothesis that the coastal population is genetically capable of exhibiting the same seasonal shift in leaf morphology as the inland plants. Would you need access to a greenhouse where you can control variables, or would it be just as easy to do experiments in the wild? Explain your reasoning and outline your experimental design—including the variable or variables you will test in the first experiment.

Figure 26.8 At what stage dees the diploid zygote form? when the female cone begins to bud from the tree at fertilization when the seeds drop from the tree when the pollen tube begins to grow

Which of the following is an advantage of asexual reproduction? Cuttings taken from an adult plant show increased resistance to diseases Grafted plants can more successfully endure drought When cuttings or buds are taken from an adult plant or plant parts, the resulting plant will grow into an adult faster than a seedling Asexual reproduction takes advantage of a more diverse gene pool.

INTERPRET DATA Flower parts are arranged in four concentric circles: sepals, petals, stamens, and carpel. According to the ABC model of floral organ development in Arabidopsis, class A genes are needed to specify sepals, the A and B genes to specify petals, the B and C genes to specify stamens, and class C genes to specify the carpel. If a mutation occurs in one of the B genes, rendering it inactive, what will the resulting flowers consist of?

Figure 26.15 If a flower lacked a megasporangium, what type of gamete would not form? If the flower lacked a microsporangium, what type of gamete would not form?