Angiosperms Flashcards

Flashcards about Angiosperms and their diversification

Coevolution

Process by which two or more species of organisms influence each other’s evolutionary pathway.

Pollination Coevolution

Pollinators foster genetic variability and plant potential for evolutionary change. Pollinators learn the flower characteristics and visit them preferentially, allowing for precise pollen transfer.

Pollination syndrome

Suites of flower traits that have evolved in response to natural selection imposed by different pollen vectors, which can be biotic or abiotic.

Coevolved flower features of Bees

Often blue, purple, yellow, or white flowers with a sweet odor, that require nectar and pollen for food.

Coevolved flower features of Birds

Often colored red, require a strong, damage-resistant structure, and copious nectar in floral tubes

Coevolved flower features of Bats

Light, reflective colors, strong odors, open at night, and copious nectar and pollen provided.

Wind Pollination

Produce pollen in copious amounts, tiny air sacs, reduced flowers, often unisexual, no petals.

Biotic Pollination by Bees

Flowers often blue, purple, or yellow, are fragrant, and have a corolla with a bilateral landing platform.

Biotic Pollination by Bats

Flowers white or pale green, with a musky odor, open at night, and are large and thick.

Biotic Pollination by Hummingbirds

Flowers red, yellow, or orange, no odor, diurnal, tubular corolla, often pendant, with adaptations to exclude insects.

Fruit Development

Develop from ovary walls, aid in the dispersal of enclosed seeds, preventing competition and aiding in colonization.

Secondary Metabolites

Synthesis of molecules that are not essential for cell structure and growth.

Terpenes and terpenoids

Taxol, citronella, rubber, turpentine, rosin, and amber.

Phenolics

Some flower and fruit colors; flavors like cinnamon, nutmeg, ginger, clove, chilies, vanilla; prevent UV damage; some are antioxidants.

Alkaloids

Caffeine, nicotine, morphine, ephedrine, cocaine, and codeine.

Abiotic Seed Dispersal

Seeds simply drop/shake to ground, float, or flutter away.

Biotic Seed Dispersal

Sticky or barbed (external) attractive, edible, nutritious (internal)

Seed Definition

A propagating organ formed in the sexual reproductive cycle of gymnosperms and angiosperms, consisting of a protective coat enclosing an embryo and food reserves.

Vivipary

The precocious and continuous growth of the offspring when still attached to the maternal plant; restricted primarily to estuarine species.

Seed Dormancy

The failure of seeds to germinate although environmental conditions including water, temperature, light and gases are favorable for germination.

Seed Banks

The natural storage of seeds, often dormant, within the soil of most ecosystems.

Seed Bank Persistence

Transient (less than 1 year), short-term persistent (1-5 years), long-term persistent (more than 5 years).

Domestication

Artificial selection for traits desirable to humans.

Shattering

Wild fruit breaks apart and disperses seeds

Human Influences on Angiosperm Diversification

Plants ~ especially tropical forests, are competing for space with humans. Predictions of loss of rainforest within 25 years due to slash & burn.

Artificial Selection

Selection of individual plants that exhibit desired characteristics; has led to the evolution of new crops that bear little resemblance to their wild ancestors

Evolution

A change in the genetic composition of a population over time

Natural Selection

The process by which organisms better adapted to their environment tend to survive and reproduce more successfully

Adaptive Trait

An inherited characteristic that enhances an organism's ability to survive and reproduce in a particular environment

Genome

The complete set of genes or genetic material present in a cell or organism

Speciation

The generation of new species, which occurs when the divergence between two populations leads to reproductive isolation

Evolutionary change above the species level, including the origin