Botany exam 4

what are 3 examples of basal angiosperms?

amborella, water lillies, stare anise

what are 3 examples of magnolids?

magnolias, laurels, black pepper plants

what are 3 examples of monocots?

banana, rice, flowering grasses

what are 3 examples of eudicots?

oak tree, round-lobed hepatica, california poppy

what percent of extant angiosperms do monocots and eudicots make up?

98%

what are characteristics of gymnosperm seeds?

naked seeds enclosed in a cone of a gymnosperm

what are characteristics of angiosperm seeds

seed vessel enclosed in a fruit of an angiosperm

what are flowers?

reproductive structure of angiosperms

what are characteristics of angiosperm flowers?

enclosed ovule and seeds

what are characteristics of gymnosperm flowers?

exposed ovules and seeds

what are features of more ancient lineages of flowering plants?

numerous flower parts that are not fused together, superior ovaries, radial symmetry

what are features of more recent lineages of flowering plants?

flower parts that have fused together, inferior ovaries, bilateral symmetry

what are characteristics of complete flowers?

calyx, corolla, androcium, gynoecium

what are calyx?

set of sepals

what are corolla?

set of petals

what are androecium?

set of stamens

what is a gynoecium?

carpel

what are characteristics of perfect flowers?

sexual whorls, gynoecium, androecium

what are characteristics of incomplete flowers?

lacking one or more of the four main whorls

what is radial symmetry?

flowers with multiple planes of mirror image symmetry

what is bilateral symmetry?

flowers with just a single plane of mirror image symmetry

what is a carpel?

vessel like an inrolled leaf with seeds along its margins

how do carpel seeds develop?

from an ovule within a carpel and is a part of an ovary that becomes a fruit

what are characteristics of angiosperms?

heterosporous, sporophytes more dominant than in gymnosperms, female gametophytes fully enclosed within sporophyte tissue and reduced to only a few cells, at maturity, male gametophytes consist of a pollen grain with three nuclei

in the development of gametophytes, what occurs while the flower is developing in the bud?

a diploid megasporocyte cell differentiates from all the other cells in the ovule

what happens to the megasporocyte in the development of gametophytes?

the megassporocyte undegoes meiosis, producing four haploid megaspores, three of these degenerate and disappear, the nucleus of the fourth undergoes mitosis, and the cell enlarges

in the development of gametophytes, what happens while the cell is growing larger?

its two haploid nuclei divide once more, the four resulting nuclei then divide another time

what happens to the two outer layers of cells of the ovule in the development of gametophytes?

they differentiate from maternal tissue, these layers, called integuments, later become the seed coat

what happens as the integuments develop in the development of gametophytes?

they leave a pore, called the micropyle, at one end of the ovule

where does the formation of male gametophytes take place?

in the anthers

what happens as an anther develops in the formation of male gametophytes?

four patches of tissue differentiate from the main mass of cells

what do the four patches of tissues in the formation of male gametophytes contain?

many diploid microsporocyte cells, each of which undergoes meiosis, producing a quartet of microspores

what happens as the anther matures in the formation of male gametophytes?

the walls between adjacent pairs of chambers break down, so that only two larger sacs remain

what happens after meiosis in the formation of male gametophytes?

the microspore divides once by mitosis to produce two cells, the members of each quartet of microspores separate from one another, a two-layered wall, whose outer layer is often finely sculptured, develops around each microspore. when these events are complete, the microspores have become pollen grains

what is the exine?

outer layer of the pollen grain wall that is often sculptured

what is a generative nucleus?

one of the pollen grains two nuclei that will later divide, producing two nuclei that become surrounded by a plasma membrane and function as sperm cells

what is a vegetative (tube) nucleus?

involved in events that take place after the pollen grain has left the anther

what is pollination?

the transfer of pollen grains from an anther to a stigma

what is fertilization?

union of egg and sperm

who is double fertilization unique to?

angiosperms

what is the first step in double fertilization?

one sperm migrates from the synergid to the egg, losing most of its protoplasm along the way

what is the second step in double fertilization?

the sperm cell nucleus unites with the egg nucleus, forming a zygote

what is the final step in double fertilization?

the other sperm cell also migrates from the synergid into the central cell nuclei, producing a triploid, endosperm nucleus

what is the endosperm?

major source of nutrition that surrounds the embryo that develops from the zygote

what is apomictically?

without fusion of gametes

what is parthenocarpic?

fruits develop from ovaries having unfertilized eggs

what is an inferior ovary?

when the ovary is embedded in the receptacle and other parts, flower parts attached at the top of the ovary are said to be epigynous

what is a superior ovary?

produced on top of the receptacle, flower parts attached around its base are said to be hypogynous

what is perigynous?

flower parts are usually attached to a corolla tube of fused petals

what are characteristics of complete flowers?

have a calyx, corolla, stamens, and a pistil

what are characteristics of perfect flowers?

have stamens and a pistil

when is something monoecious?

when both male and female imperfect flowers occur on the same plant

when is something dioecious?

if a plant bears only male flowers and other plants of the same species bear only female flowers

what are herbaria?

essentially libraries of dried, pressed plants, algae and fungi, arranged and labeled

how do flowers develop fruit?

the ovary of flowers, once pollinated and the ovules fertilized, ripen into fruits containing seeds. seeds germinate to produce new seedlings, which mature into reproductive adults

what is pericarp?

the outermost part of most of fruits that develop from ripened ovary wall after fertilization, surrounds,protects, and helps disperse the seeds

what is exocarp?

thin and tough outermost covering of the pericarp that accounts for the outermost covering of the pericarp and forms the fruit rind or peel

what is the mesocarp?

fleshy or dry middle layer that accounts for an intermediary layer, tends to be the edible portion of the fruit

what is the endocarp?

accounts for the innermost layer of the pericarp, straightaway encloses the seed

what are characteristics of citris endocarp?

only edible portion

what are characteristics of stone fruit endocarp?

thick and hard

what are characteristics of dry fruit endocarp?

hardcover enclosing the kernel

what are characteristics of simple fruits?

derived from the ovary of a single carpel or several fused carpels

what are pomes?

a simple, fleshy fruit with the ovaries enclosed in a “floral cup” that develops from the receptacle, an accessory fruit because it contains tissue derived from plant parts other than the ovary

what are stone fruits/drupes?

a simple fruit with a thin exocarp, a fleshy mesocarp, and a hard, stony endocarp that encases the seed

what are berries?

simple fruit with a thin exocarp, a soft, fleshy mesocarp, and an endocarp enclosing one to many seeds

what are pepos?

a specialized berry with a tough outer rind consisting of both receptacle tissue and exocarp

what are hesperidiums?

a type of berry, with the exocarp and mesocarp as a hard rind and the endocarp composed of juice vessels

what are two examples of dry, dehiscent fruits that open at maturity to reveal the seeds?

legumes, milkweed

what is an example of a dry, indihiscent fruit that does not open at maturity

nuts - single seed fused to the ovary wall and a very hard pericarp

how are aggregate fruits developed

from a single flower with many separate carpels

what are two examples of aggregate fruits?

raspberry, strawberry

how are multiple fruits developed?

from the fusion of ovaries from many separate flowers on inflorescence

what is an example of a multiple fruit?

pineapple

what is 1?

cotyledon

what is 2?

plumule

what is 3?

embryonic stem and root

what is 4?

radicle

what is 5?

seed coat

how do flowers improve reproductive success?

enhanced pollination efficiency, promotes cross pollination, precise pollen delivery, reduced wasted pollen, protection of reproductive organs

do animals increase or decrease the likelihood of successful pollen transfer?

increase

how is cross pollination beneficial?

increasing genetic diversity and adaptive capacity of populations

how do fruits improve reproductive success?

protect developing seeds and reduce damage to offspring, enhance seed dispersal, increase colonization success

what does dispersal away from the parent plant do?

reduce competition

what is competition?

individuals of different species each use a limited resource, reducing the survival or reproduction of both individuals

what is exploitation?

members of one species benefit by feeding upon members of the other species

what is predation?

an individual of one species, the predator, kills and eats an individual of the other, they prey

what is herbivory parasitism?

a herbivore eats part of a plant or algae, the parasite derives its nourishment from a second organism, its host

what are positive interactions?

members of one species benefit, while members of the other benefit or are not harmed

what is mutualism?

members of both species benefit from the interaction

what is commensalism?

members of one species benefit, while members of the other are not affected

what do plants provide in plant-pollinator mutualism?

food, shelter

what do pollinators provide in plant-pollinator mutualism?

dispersal of plant genes

what do pollinators receive in plant-pollinator mutualism?

pollen, nectar, oils

what are benefits of animal pollination?

increases the chance of recieving pollen from an unrelated individual, advantageous in low wind conditions, less pollen production necessary

what are costs of animal pollination?

energetically costly

what is plant-seed mutualism?

flesh, nutritious fruits evolved to encourage animals to consume them and disperse seeds. Animals transport seeds away from parent plants, reducing competition and promoting colonization of new habitats

what is ecology?

a broad, integrated discipline that examines the relationships of organisms to each other and to their environment

what are populations?

groups of individuals of the same species

what are communities?

composed of populations of different species living together in the same place