Exam 38: Plant Reproduction and Development

Which of these events occurs first in seed germination?

Mosses and ferns tend to be most abundant in warm, moist climates. Why do mosses and ferns have problems with reproduction in deserts?

It is estimated that animal- or insect- pollinated plants produce 1000 pollen grains for each ovule; wind- pollinated plants produce 1,000,000 pollen grains for each ovule. What does that indicate about pollination systems?

Which of these is not a step in the formation of an embryo from a zygote in the seed?

Which of these events happens first in nearly all seed germination?

A summer occupation in the Corn Belt states is de- tasseling the corn: removing unwanted male flowers so that female flowers on the same plant are pollinated by the desired pollen for the hybrid corn. What does this tell you about corn?

What is not true about the carpel of a flower?

ABC model of floral development -According to the ABC model of floral development , which genes would be expressed in a showy ornamental flower with multiple sepals and petals but no stamens or carpels?

What is the male gametophyte made of?

Which theory have biologists associated with the occurrence of pollination syndrome?

In the early plant embryo, cells divide asymmetrically. Which structure does not result from divisions of the apical terminal) cell?

Which of the following is another name for the female gametophyte?

It is possible to make seedless tomatoes by removing the anthers of the flower and putting a hormone auxin) on the stigma of the tomato flower. Weekly applications are required. Over the course of development, the stigma and style fall off, and the ovary develops into a normal- looking tomato with no seeds. Normally, seed and fruit formation are coordinated using hormone signaling. What does the application of auxin indicate?

Meristematic tissue cells in plants are most similar to which kind of cells in animals?

ABC model of floral development -Based on the ABC model , what would be the structure of a flower from the outermost whorl that had normal expression of genes A and C and expression of gene B in all four whorls?

Cottonwood, aspen, and willow trees have drab- coloured flowers with no petals that appear before the tree's leaves are out in the spring; they are dioecious. What does that indicate about these trees?

Unripe fruits protect seeds from predation and early germination. What is the major function of ripe fruits?

The egg of a plant has a haploid chromosome number of 12 n = 12). What is true about the number of chromosomes in the cells of other tissues of this plant?

A population of flowers varies from deep blue to nearly white. Bees are active during the day and prefer colour. Moths are active at night, when colours are not very visible and white is more conspicuous. Design a scenario in which the blue and white flowers form two species where there once was one species. You must end with a conclusion that the two new species cannot interbreed a definition of a species).

Before plowing a field, a farmer thought the bare field looked weed- free. Three days after plowing and turning over the soil, he was amazed to see thousands of tiny seedlings. What kinds of seeds did the plowing help with germination?