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Biology Test 2-Anfiosperms

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Angiosperms
seed plants with reproductive structures called flowers and fruits
What are the reproductive structures of Angiosperms
fruits
flowers
Angiosperms are classified in what phylum
Anthophyte
The two main groups of angiosperms are
Monocot
Eudicot-Dicots
but there are 2 other sm groups..Basal Angiosperms and Magnolids
Monocot means
one cotyledon
Eudicot/Dicot means
more than one cotyledon
Basal Angiosperms
less derived and include the flowering plants belonging to the oldest lineages
Magnolids
another type of angiosperm that share some traits with basal angiosperms but are more closely related to monocots and eudicots
what small lineages constitute the basal angiosperms?
Amborella trichopoda
water lilies
star anise
what is a trait of the basal angiosperms
short stalks
What are the three lineages of the Magnolids
magnolias
laurels
black pepper plants
Between the Magnolids and Basal Angiosperms which is more closely related to the monocots and eudicots
Magnolids
What percentage of angiosperm species are monocots?
25%
What kind of plants are monocots?
grasses; such as barley
How much does the Eudicots make up of the angiosperms species?
more than 2/3
Examples of Eudicots
Snow Pea
Zucchini Flower
Number of cotyledons: Dicot vs Monocot
D-2
M-1
Leaf Veination: Dicot vs Monocot
D-netlike
M-usually parallel
Stems: Dicot vs Monocot
D-vascular tissue usually arranged in ring; Pholem inside Xylem outside
M-Vascular tissue scattered
Roots: Dicots vs Monocot
D-taproot present
M-Root system usually fibrous
Pollen: Dicots vs Monocot
D-pollen grain with three openings
M-pollen grain with one opening
Flowers: Dicot vs Monocot
D-floral organs usually in groups of 4 or 5
M-floral organs usually in multiples of 3
The flower is an angiosperm structure specialized for
sexual reproduction
How may these species be pollinated?
insects
animals
wind
4 modified leaves of a flower
sepals
petals
stamens
carpels
Sepals
enclose the flower and located near the base
Petals
brightly colored and attract pollinators
These modified leaves produce pollen on their terminal ___
Stamens
anthers
This modified leave produces ovules
carpel
the carpel consist of what 3 major parts
stigma
style
ovary
the stamen consists of 2 major parts
anther
filament
In the angiosperm where are the male gametophytes contained?
pollen grains
pollen grains are produced by the micrsporangia of ___?
anthers
Another name for the female gametophye?
embryo sac
The embryo sac develops within an ___ contained within an ___ at the base of a stigma
ovule
ovary
cross-pollination
pollination between flowers form different plants of the same species
process of the pollen grain
stigma-->down style--->pollen tube forms--->ovary
Gymnosperms have single fertilization while angiosperms have ___ fertilization
double
double ferilization
when the pollen tube discharges two sperm into the female gametophyte within an ovule
the ovule is entered by a pore called the
micropyle
What are the three things the 2 sperms does?
fertilizes the egg
combines with two nuclei in the central cell of the female gametophyte
initiates development of food-storing endosperm
what does the endosperm do?
nourishes the developing embryo
cotyledon
seed leaves
what does the embryo consist of?
root
2 seed leaves-cotyledons
Figure 30.10-4
...
what does the fruit do for the seeds?
protect seeds
aid in dispersal
Mature fruits cand either be
fleshy
dry
Examples of fleshy fruits
tomatoes
grapefruits
nectarines
Examples of dry fruits
milkweed
hazelnut
How can seeds be dispersed
wind
water
animals
What are tow important relationships in terrestrial ecosystems
pollination of flowers
transport of seeds by animals
Bees pollinate
1/3 of crops and food in the diet of U.S. citizens
The monetary value of honey bees as commercial pollinators in the US is estimated at about
15-20 billion annually
Human welfare depends greatly on
seed plants
what percentage do wheat rice maize potatoes cassava and sweeet potatoes amount to in calories consumed by humans
40
At the current rate of habitat loss what percent of earths species will be come extinct within the next 100-200 years
50
Figure 30-UN3
...
Three F's of angiosperm life cycle
flowers
fertilization
fruits
What are the reproductive parts of the flower?
stamen
carpel
flowers are the reproductive shoots of the angiosperm ___?
sporophyte
the flower attaches to a part of the stem called the?
receptacle
a single carpel or group of fused carpels
pistil
flowers consist of four floral organs
sepals
petals
stamen
carpel
which flowers contain all four floral organs?
complete flowers
which flowers lack one or more floral organs, for example stamens or carpels
incomplete flowers
clusters of flowers are called
inflorescences
anther->____-> ____->meosis->4 ___-> haploid male gamete
microsporangia
microsporocytes(2n)
microspores (n)
If pollination succeeds, a ____ produces a ____ that grows down into the ovary and discharges sperm near the embryo sac
pollen grain
pollen tube
what does the pollen grain consist of?
two-celled male gametophyte
spore wall
the microspores contain 2 cells
generative cell
tube cell
where are the antipodal cells located
the upper portion of the embryo sac
what are the cells on either side of the egg
synergids
what role to the synergids have?
tell the pollen tube where to connect
This results form the discharge of 2 sperm from the pollen the into the embryo sac
double fertilization
One sperm fertilizes the egg, and the other sperm does?
combines with the polar nuclei, giving rise to the triploid food-storing endosperm
what does double fertilization ensure?
the endosperm develops only in the ovules where the egg has been fertilized
In most monocots and some eudicots the endosperm stores?
nutrition
After double fertilization what develops into a seed?
ovule
What develops into the fruit enclosing the seed (s)?
ovary
In other eudicots, the food reserves of the endosperm are exported to the
cotyledons
The first mitotic division of the zygote is transverse, splitting the fertilized egg into what two cells?
basal cells
terminal cells
The basal cells create the
roots
the terminal cells create the
shoots
the embryo and its food supply are enclosed by a hard protective coat know as
seed coat
When the seed doesn't have the right conditions to grow it will enter a state of
dormancy
cotyledons
seed leaves
In some eudicots, such as the common garden bean, the embryo consists of the embryonic axis attached to
two thick cotyledons
above the cotyledon is called the
epicotyl
below the cotyledon the embryonic axis is called the
hypocotyl
the hypocotyl terminates in the
radical
Figure 38-8a
...
a monocot embryo has
one cotyledon
grasses, such as maize and wheat, have a special cotyledon called
scutellum
Two sheathes enclose the embryo of a grass seed; what are they?
coleoptile
colerhize
the coleoptile covers
the young shoot
coleorhize covers
the young root
Breaking seed dormancy often requires environmental cues, such as
temp
light
Germination depends on
imbibition
imbibition
the uptake of water due to low water potential of the dry seed
what emerges from the see first
radicle
After the radicle the ___ breaks through the soil
shoot tip
In many eduicots, a hook forms in the ___ and growth pushed the hook above ground
hypocotyl
what does the hook pull up
cotyledons and the shoot tip
In maize and other grasses, which are monocots, the ___ pushed up thorugh the soil
coleoptile
what depelops from the ovary
fruit
what does the fruit provide for the seeds
protection
aids in dispersal by wind or animals
how is a fruit classified as dry?
ovary dries out at maturity
how is a fruit classified as fleshy
if the ovary becomes thick, soft and sweet at maturity
Three types of fruit
simple
aggregate
multiple
simple fruit
single or several fused carpels; apples
aggregate fruit
a single flower with multiple separate carpels; berry
multiple fruit
group of flowers called an inflorescence; pineapple
accessory fruit
contains other floral parts in addition to ovaries
sexual reproduction
results in offspring that are genetically different from their parents
asexual reproduction
results in a clone of genetically identical organisms
fragmentation
separation of a parent plants into parts that develops into whole plants, is a very common type of asexual reproduction
asexual reproduction is also know as
vegetative reproduction
Problem of asexual reproduction
a clone of a plant is vulnerable to local extinction if there is an environmental change
Benefit of sexual reproduction
generate genetic variation that makes evolutionary adaptation possible
problem of sexual reproduction
only a fraction of seedlings will survive
dioecious species
have staminate and carpellate flowers on separate plants
What is another way besides that of dioecious species to prevent selfing
stamens and carpels mature at different times or are arranged to prevent like that of the Thrum and Pin flower.
Thrum-stamen tall style short; Pin flower-style tall stamen short
self-incompatibility
a plants ability to reject its own pollen
How plants recognize self-incompatibility
if the pollen has a S gene matching an allele in the stigma cells
triggers a signal transduction pathway leading to a block in growth of a pollen tube