Plant Biology Review Flashcards

Flashcards to review plant biology concepts, including evolution, speciation, plant ecology, biomes, and gymnosperms.

What is the difference between evolution and speciation?

Evolution refers to changes in genetic traits in a population over time, while speciation is the formation of new, distinct species from a common ancestor.

What is ancestral species vs derived species?

Ancestral is origin species, derived species comes from ancestral species

What is a species

organisms that share the same gene pool

Micro evolution vs macro evolution

Micro evolution is change within a species, macro evolution is changes that go beyond the level of species and no longer share a gene pool

Impacts on dom vs recessive

Dominant genes are immediately acted on by selection, recessive genes need to wait for high enough frequency

Example of allopathic speciation

A river is cuz and the population is now split into 2 different gene pools

Sympathetic speciation

More rare, share the same environment

Diane Dodd experiment

Took ancestral population of fruit flies and fed them starch and maltose to see what would happen

Hybrid sympathetic speciation

Putting two species together could create a third with a mutation

Prezygotic isolation

How species stay separate

Chromosomal differences

Variations in the number, structures, composition, which can lead to genetic disorders

Postg zygote isolation

Zygote forms but is not viable or non reproductive

Hybrid necrosis

Immune system attacks foreign protein

What group had dominant gametophytes

Mosses

Do true tissues have autotrophy and nuclei in their cells

Yes, true plants are made of eukaryotic cells

What moss produces acid and is found in bogs

Sphagnum moss

What phylum produces spores but has no vascular tissue

Bryophyta (mosses)

What do the archegonia in mosses enclose

The egg cell

What group is sensitive to pollution bc it has no cuticle

Lichens

What spore producing plant has Cyanobacteria

Hornworts

What plant group has a rhizome and commonly microphylls in most members

Lycophytes

Who belongs to polypodiophyta

True ferns

What plants form coal deposits

Seedless vascular plants, like Lycophytes and ferns

What is the dominant phase in horsetails

The sporophyte

How and when did vascular plants come to land

430 mill years ago, through adaptations like vascular tissue, cuticles, and stomata

How are gymno sperms different from mosses and ferns

Seeds, vascular tissue, dominant sporophyte, heterospory

What is strobilus

A cone like structure that hold sporangia, common in club mosses, horsetails and conifers

Tundra biome:

Artic and alpine regions, cold, dry, permafrost, short growing season, poor soil, alpine is at high elevations with no permafrost, arctic is at high latitudes

Taiga:

Warmer temps, deeper soils, longer growing seasons, no permafrost,

Temperate deciduous forest

Long growing season, 4 seasons

Chaparral

Hot, dry, dense small trees, adapted to fires and droughts, found in Mediterranean areas, evergreens, coastal cali

Temperate grasslands

Moderate rainfall, hot summers, cold winters, dominated by grasses, good growing season,

Tropical grasslands

Distinct wet and dry seasons, unpredicted rain, occurs between tropical rainforests and deserts, drought tolerant grasses

Deserts

Less than 25 cm of rain a year, 30 degrees N and S of equator, succulents, cam photosynthesis, sandy soil, high evaporation

Tropical forests

Warm temps year round, most biodiversity,

What is the title and publication date of Darwin’s work?

On the Origin of Species, published in 1859.

Who motivated Darwin’s work on evolution?

Thomas Malthus, whose ideas on population growth and limited resources influenced Darwin’s thinking.

What are the five main components of Darwin’s theory of evolution?

1. Variation exists in populations 2. Traits are heritable 3. More offspring are produced than can survive 4. There is differential survival and reproduction 5. Beneficial traits become more common over generations

What are nine types of evidence that support Darwin’s theory?

1. Fossil record 2. Homologous structures 3. Embryology 4. Biogeography 5. Molecular biology 6. Vestigial structures 7. Observable evolution 8. Artificial selection 9. Comparative anatomy

What do gametophytes produce?

Gametes (sperm and egg cells).

What do sporophytes produce?

Spores.

What do spores develop into?

Gametophytes.

What do gametes unite to form?

A zygote.

What is dichotomous branching?

A form of branching where the stem splits into two equal parts.

Why is Chara important to plant evolution?

It’s a green alga closely related to land plants, showing evolutionary links.

Which plant group has a dominant gametophyte generation?

Bryophytes (like mosses).

Which group has true tissues, is autotrophic, and has nuclei in their cells?

Land plants.

What moss produces acid in its tissues and is found in bogs?

Sphagnum moss.

Which phylum produces spores but has no vascular tissue?

Bryophyta.

In which phylum are antheridia and archegonia found in mosses?

Bryophyta.

Where are spores produced in mosses?

In the sporangium at the tip of the sporophyte.

Which group is sensitive to pollution because it has no cuticle?

Liverworts.

What spore plant has a symbiotic relationship with Cyanobacteria?

Azolla.

Which group has a dominant sporophyte and produces spores?

Ferns.

Which plant group commonly has rhizomes?

Ferns.

In which plant group are microphylls common?

Lycophytes.

Which plants have cell walls containing carbon and silica?

Horsetails (Equisetum).

Who belongs to the phylum Polypodiophyta?

True ferns.

The plant deposits found in fossil fuels are remains of which group?

Ancient ferns and fern allies.

What is the dominant phase in the lifecycle of Equisetum?

Sporophyte.

What is the earliest known land plant?

Cooksonia.

What did Cooksonia look like?

It had terminal sporangia and no true leaves.

What are key adaptations for living on land?

Cuticle, vascular tissue, stomata, and seeds.

Why is Rhynia important to plant evolution?

It shows early development of vascular tissues in land plants.

How are gymnosperms different from mosses or ferns?

Gymnosperms produce seeds and have a dominant sporophyte, while mosses and ferns rely on spores and often require water for reproduction.

What is heterospory?

The production of two different types of spores: microspores (male) and megaspores (female).

What is the gametophyte generation in gymnosperms?

It’s microscopic and retained within the cones—female gametophytes develop in ovules; males in pollen grains.

How are cycads fertilized?

By flagellated sperm that swim to the egg, often aided by beetles or wind.

Are cycads bisexual or unisexual?

Unisexual—there are separate male and female plants.

What is a strobilus?

A cone-like reproductive structure found in many gymnosperms.

To which phylum does Ginkgo biloba belong?

Ginkgophyta.

Is Ginkgo biloba unisexual or bisexual?

Unisexual—it has separate male and female trees.

What are the three main genera in Gnetophyta?

Ephedra, Gnetum, and Welwitschia.

What use does Ephedra (Navajo tea) have?

Traditionally used for medicinal purposes and herbal tea.

To which phylum do pines, spruces, and redwoods belong?

Coniferophyta.

A woody pine cone is of which gender?

Female.

How do pines reproduce?

Via wind-pollinated cones producing seeds on scales.

What is dendrology used for?

The scientific study of trees.

Where are most redwoods distributed today?

On the west coast of North America, especially in coastal California.

Which plants have seeds that are “naked” on bracts instead of enclosed in fruit?

Gymnosperms.

Do gymnosperms need free water for reproduction?

No, they rely on wind to transport pollen.

What phylum do Ginkgo, Ephedra, and Welwitschia belong to?

Ginkgo: Ginkgophyta, Ephedra & Welwitschia: Gnetophyta.

What ecological advantage do gymnosperms have over ferns?

Seeds provide protection and sustenance, allowing them to thrive in drier environments.

Name the four phyla of gymnosperms and a representative of each.

● Coniferophyta (Pinus) ● Ginkgophyta (Ginkgo biloba) ● Cycadophyta (Cycas) ● Gnetophyta (Ephedra)

How is the dawn redwood (Metasequoia) a living fossil?

It was known only from fossils until living specimens were discovered, showing little evolutionary change.

What happens during the development from a megaspore mother cell to an embryo?

The megaspore mother cell undergoes meiosis to form four megaspores, one of which develops into the female gametophyte, which eventually forms the embryo after fertilization.

What does a fertilized egg cell become?

It becomes the zygote, which then develops into the embryo.

What do the polar nuclei become when fertilized?

The polar nuclei fuse with one sperm cell to form the endosperm, which nourishes the developing embryo.

What is double fertilization, and which plants have it?

Double fertilization is the process where one sperm fertilizes the egg, forming the zygote, and another sperm fertilizes the polar nuclei, forming the endosperm. It occurs in angiosperms (flowering plants).

What is the microphyle/hilum?

The microphyle is the small opening through which the pollen tube enters the ovule, while the hilum is the scar on the seed where it was attached to the ovary wall.

What are two developmental patterns in zygotes?

The two patterns are the development of the embryo within the seed and the growth of the seedling from the seed after germination.

What embryo types are found in monocots and dicots?

Monocots have one cotyledon, while dicots have two cotyledons.

What does the epicotyl become?

The epicotyl becomes the shoot of the plant, including the stem and leaves above the cotyledons.

What does the hypocotyl become?

The hypocotyl becomes the part of the stem below the cotyledons, connecting to the root.

What protects the young shoot/root in corn seeds?

The coleoptile protects the young shoot, and the coleorhiza protects the young root.

What are the four steps to seed maturation?

The four steps are: 1. Development of the embryo. 2. Accumulation of food reserves. 3. Formation of a seed coat. 4. Drying and dormancy of the seed.

What is a quiescent seed, and which plants have them?

A quiescent seed is a seed that is alive but not actively growing; it remains dormant until favorable conditions occur, like in many temperate plants.

What does a dormant seed require to grow?

It requires the right environmental conditions, such as water, light, temperature, and sometimes physical damage or chemical treatments to trigger germination.

What is scarification (mechanical and chemical)?

Scarification is the process of breaking or softening the seed coat to allow water to enter, triggering germination. Mechanical scarification involves physical abrasion, and chemical scarification uses chemicals to weaken the coat.