Question

A pollinator may receive _____ when it visits a flower of a coevolved plant (choose all that apply). a. pollen b. nectar c. pathogens d. fruit

Short answer

Pollinators may receive pollen, nectar, and pathogens.

Step-by-step solution

Understand the Context of Pollination

Pollination is the process by which pollen is transferred from the male part of a flower (the anther) to the female part of a flower (the stigma). Pollinators such as bees, birds, and bats visit flowers to obtain resources that help them survive.

Review the Pollinator Rewards

Flowers often provide rewards to attract pollinators. Common rewards include pollen and nectar. Nectar is a sweet liquid that provides energy to the pollinator, while pollen can be collected by some pollinators as a protein source.

Consider Possible Risks for Pollinators

While visiting flowers, pollinators can also encounter pathogens. These can be bacteria, fungi, or viruses present on the flowers, which may inadvertently be transported by the pollinator.

Evaluate Other Possible Floral Visits

Typically, fruit is not provided to pollinators by flowers. Fruits develop from the fertilized ovary after pollination and are generally not a resource that pollinators collect during their visits to flowers.

Analyze the Options and Choose

Based on our understanding: - Pollen (a) can be collected by pollinators as a food source. - Nectar (b) is a primary reward for pollinators. - Pathogens (c) may be present and affect pollinators. - Fruits (d) do not apply as they are not typically the purpose of a pollinator’s visit.

Key concepts

Pollinator Rewards

Pollinators like bees and butterflies are drawn to flowers by the promise of rewards. These rewards are essential for the survival of both the pollinators and the plants. The most common rewards offered by flowers include:

• Pollen: This is a valuable source of protein for many pollinators. Some insects, like bees, collect pollen to feed their young or to consume themselves.
• Nectar: A sugary liquid, nectar is a key source of energy for pollinators. When a pollinator sips nectar, it often ends up brushing against the flower's reproductive structures, inadvertently aiding in pollen transfer.

These rewards ensure that pollinators keep visiting flowers, thereby facilitating the process of pollination.

Pollen Transfer

When a pollinator visits a flower in search of nectar or pollen, it plays an accidental yet crucial role in the plant's reproductive process. Pollen transfer involves moving pollen grains from the male anther to the female stigma.

• As pollinators reach deep into flowers for nectar, they come in contact with the anthers, coating themselves with pollen.
• Upon visiting another flower, the pollen is then transferred to the stigma, potentially leading to fertilization.

This exchange is mutualistic as plants achieve reproduction, while pollinators receive necessary nutrients.

Nectar

Nectar is a sweet, sugary liquid produced by the flower’s nectaries, situated within or near the floral structures. It serves as the main attraction for pollinators because of its high energy content.

• Nectar's primary role is to entice pollinators to visit the flower. While the pollinator drinks it, there is a high chance of pollen attachment.
• The sweetness of nectar varies among plants, often attracting different types of pollinators like bees, butterflies, or hummingbirds.

The strategical placement of nectar ensures that pollinators must make contact with pollen-rich areas, aiding in the pollination process.

Coevolution of Plants and Pollinators

The intricate dance between plants and their pollinators is a result of a process called coevolution. This is where two or more species reciprocally affect each other’s evolution.

• Plants evolve features like the shape, color, and scent of their flowers to efficiently attract specific pollinators.
• Pollinators, in turn, develop traits that increase their efficiency in locating and extracting rewards from plants.

Over time, these adaptations lead to highly specialized relationships, sometimes to the extent that certain plants depend on only one type of pollinator. Such coevolution ensures the survival and reproductive success of both plants and their pollinators.