Evaluate these statements about double fertilization. Select True or False for each sentence.

T/F Two zygotes are formed, but only one survives.

T/F One sperm fuses with an egg while the other sperm fuses with polar nuclei.

T/F It results in the formation of a diploid embryo and triploid endosperm.

T/F Both sperm involved in double fertilization form within the same pollen tube.

In angiosperms, are sperm and eggs produced by mitosis or meiosis?

Which cells are spores?

Which structures are gametophytes?

Which of the following does not occur during embryogenesis?

a. Formation of the radial axis

b. Production of the suspensor

c. Formation of the cotyledons and hypocotyl

d. Formation of the leaf lateral and proximal–distal axes

When does the apical–basal axis first become apparent?

a. When the epidermal, ground, and vascular tissues form

b. When the cotyledons, hypocotyl, and root form

c. When the first cell division produces the apical cell and basal cell

d. During the globular stage, when the suspensor is complete

Why is the emergence of the radicle an important first step in germination?

a. Its hook helps protect the shoot that emerges later.

b. It carries out photosynthesis to supply the embryo with food.

c. It is important for establishing a supply of water to the growing embryo.

d. It is necessary to break the seed coat.

What are the advantages and disadvantages of self-fertilization versus those of outcrossing?

In what sense are the tissues produced in the shoot and root apical meristems of a 300-year-old oak tree 'embryonic'?

Human embryonic stem cells are capable of forming all types of cells in the human body. How are these cells similar to meristem cells in plants?

Consider the following fruits: an acorn, a cherry, a burr, and a dandelion seed. Based on the structure of each of these fruits, predict how the seed is dispersed.

Design a study that would estimate the average distance that each type of seed is dispersed from the parent plant.

Make a sketch of a simplified flower with all four organs, and indicate how the pattern of expression for just two genes (e.g., 'D' and 'E') could, hypothetically, regulate the development of each organ.

Consider that what's important is whether a gene is on or off and that a structure can be specified when neither gene is expressed.

Most flowering plants can achieve pollination in several different ways. Those that produce pollen and carpels on the same plant may be self-pollinated, but they may also be cross-pollinated by insects or other pollinators. The cape gooseberry (Physalis peruviana) shown here is able to produce seed whether it is self- or cross-pollinated.

Is one type of pollination better for reproductive success than the other?

Considering the gooseberry flower shown here, what types of cues might attract bees to the plant?

What type of rewards do bees seek?

Most flowering plants can achieve pollination in several different ways. Those that produce pollen and carpels on the same plant may be self-pollinated, but they may also be cross-pollinated by insects or other pollinators. The cape gooseberry (Physalis peruviana) shown here is able to produce seed whether it is self- or cross-pollinated.

Is one type of pollination better for reproductive success than the other?

Researchers conducted controlled experiments to test for effects of different types of pollination on cape gooseberry fruit size and seed production. The types of pollination included self-pollination, cross-pollination by bees, and manual cross-pollination (transferring pollen from one plant to another by hand). Results are shown in the graphs here. Compared to self-pollination, do bees have a significant impact on fruit mass?

How about on seed formation?

Most flowering plants can achieve pollination in several different ways. Those that produce pollen and carpels on the same plant may be self-pollinated, but they may also be cross-pollinated by insects or other pollinators. The cape gooseberry (Physalis peruviana) shown here is able to produce seed whether it is self- or cross-pollinated.

Is one type of pollination better for reproductive success than the other?

Why might it be advantageous for plants to promote cross-pollination?

What are the advantages of self-pollination?

Most flowering plants can achieve pollination in several different ways. Those that produce pollen and carpels on the same plant may be self-pollinated, but they may also be cross-pollinated by insects or other pollinators. The cape gooseberry (Physalis peruviana) shown here is able to produce seed whether it is self- or cross-pollinated.

Is one type of pollination better for reproductive success than the other?

In general, larger fruits tend to earn higher profits for farmers who grow cape gooseberries as a crop.

Compared to self-pollinated flowers, what is the approximate percentage of difference in fruit size of bee-pollinated flowers?

Most flowering plants can achieve pollination in several different ways. Those that produce pollen and carpels on the same plant may be self-pollinated, but they may also be cross-pollinated by insects or other pollinators. The cape gooseberry (Physalis peruviana) shown here is able to produce seed whether it is self- or cross-pollinated.

Is one type of pollination better for reproductive success than the other?

Based on the data in the graphs provided, approximately how many ovules are found in each gooseberry carpel?

Most flowering plants can achieve pollination in several different ways. Those that produce pollen and carpels on the same plant may be self-pollinated, but they may also be cross-pollinated by insects or other pollinators. The cape gooseberry (Physalis peruviana) shown here is able to produce seed whether it is self- or cross-pollinated.

Is one type of pollination better for reproductive success than the other?

Global bee populations have been declining over the past decade.

What impact might this have on the world's human population?