-
Seed plants originated ______ years ago!
360 Million years ago!!
-
Seed:
Embryo and it's food supply surrounded by a protective coat
-
Traits of a seed:
- Seeds can move away from mother plant
- Seed plants are dominant producers on land
- 12,000 years ago humans began cultivating plants
-
Which type of plants are dominant producers on land?
Seed plants
-
____ years ago humans began cultivating plants.
12,000 years ago
-
What are the two key adaptions for life on land for plants?
-
Name the 5 derived traits of seed plants (ReGa HOPS)
- Reduced Gametophytes
- Heterospory
- Ovules
- Pollen
- Seeds
-
Reduced gametophytes: microscopic male and female gametophytes (n) are nourished and protected by the _____ (2N).
Sporophyte(2n)
-
Heterospory:
- microspore gives rse to male gametophyte
- megaspore-gives rise to female gametophyte
-
What heterospory:
two different types of spore
-
Microspore:
gives rise to male gametophyte
-
Megaspore:
gives rise to female gametophyte
-
What happens in the Ovules?
Inside each ovule a female develops from a megaspore and and produces one or more eggs.
-
What are the advantages of pollen?
- grains make water unnecessary for fertilization;
- pollination occurs when pollen is transferred to the part of the seed plant that contains the ovules
-
What is the advantage of Seeds vs spores?
- seeds survive better than unprotected spores
- can be transported long distances (by wind or animals)
-
Gymnosperms:
Plants with "naked seeds"
-
Why are gymnosperms called "naked seeds" ?
Beause the ovules are not completely enclosed in sporophyte tissue at pollination
-
Does pollination occur before or after fertilization?
Before!! The gymnosperm must be pollinated before it can be fertilized.
-
Pollination:
pollen has been deposited on the female part of the plant
-
Fertilization:
fusion of sperm and egg nucleus
-
What are the 4 groups of gymnosperms? (ccgg)
- 1. coniferophytes
- 2. cycadophytes
- 3. gnetophytes
- 4. ginkgophytes
-
Which gymnosperms lack flowers and true fruits?
ALL OF THEM!
-
What is the largest gymnosperm phylum?
Conifers
-
Name the traits of Conifers, and give some examples:
- Tallest and oldest vascular plants
- pines
- spruces
- firs
- cedars
-
____ are an exemplary conifer genus
Pines
-
Characteristics of pines
- Clusters of two to five rough, needlelike leaves
- produce male and female cones
- microsporangia develops into four-celled(n) pollen grains
- megasporangium(2n) produces megaspores one of which becomes female gametophyte (2n)
-
The microsporangia of pines develop into ___ celled pollen grains.
four-celes (haploid)
-
Megasporangum produces ____
megaspores
-
One of the megaspores produced by megasporangium in pines becomes the _____.
female gametophyte (diploid)
-
Which of the following components of the pine life cycle is haploid?
A. four-celled pollen is haploid (n)
-
In a fertilized pine gametophyte, which components are diploid and which are haploid?
a. seed coat
b. food reserve
c. embryo
- Diploid: seed coat
- Haploid: Food reserve, embryo
-
Cycads resemble ___ but are NOT flowering plants.
Palms
-
Cycads:
- Heights of 15 meters or more
- Produce cones
- Some female cones are huge
- Sperm have flagella
- Life cycle like that of conifers
-
Gnetophytes:
- Only gymnosperms to have vessels in their xylem
- Welwitschia from southwest Africa
- Ephedra found worldwide; source of ephedrine
-
Which gymnosperms are the only ones to have vessels in their xylem?
Gnetophytes
-
Name two Gnetophytes:
- Welwitschia - found in southwest Africa
- Ephedra - worldwide
-
This gnetophyte is the source of Ephedrine
- Epherda (Mormon Tea)
- Taken off the market because it is linked to strokes and heart attacks
-
Ginkophytes
- Only one species remains in existence
- Ginko Biloba- has broad leaves that are shed in the fall
- Sperm have flagella
- Diecious
- Fleshy covering of female seeds is very stinky like rancid butter
-
What does Dioecious mean?
Two houses: separate male and female trees (Gingko Biloba)
-
What is the only species of ginkophyte left?
Gingko biloba
-
Which two types of gymnosperm have sperm with flagella?
-
Angiosperms, aka...
The flowering plants
-
There are more than _____ known species of angiosperms.
250,000
-
What are the two defining characteristics of Angiosperms?
- Enclosed ovules within diploid tissue at the time of pollination
- Produce fruit (from the carpel)
-
What was the first angiosperm?
- Angiosperm origins are a mystery!
- Amborella trichopoda are thought to be the closest living relative to the first angiosperm
-
Two clades of angiosperms?
- Archaefructaceae (extinct family) may be a sister clade, but debated
- Amborella trichopoda
-
What houses the gametophyte generation of angiosperms?
The flower
-
What are flowers, reallt?
Modified stems that bear modified leaves
-
Flowers have ___ whorls:
Four
-
Name the 4 whorls of a flower, from the inside to the outside (GAPS):
- Gynoecium (female house) = one or more carpels
- Androecium: (male house) = stamens
- Petals: 3-5 and often colored
- Sepals: 3-5 and green, leaflike
-
Stamens produce (diploid/haploid) pollen (the male gametophyte)
HAPLOID pollen
-
Carpel has three major regions:
-
In angiosperms, the ___ becomes the fruit.
The ovary
-
Carpals contain the (male/female) gametophyte
Female
-
Why are fruits adapted?
For dispersal
-
What are the three layers of the ovary wall?
-
Collectivly, the three layers of the ovary wall (exocarp, mesocarp, and endocarp) are known as _____.
the Pericarp.
-
The fates of the three layers of the ovary determine wheather the fruit is ____, or ____ and ____.
Fleshy, or dry and hard
-
Why have angiosperms produced seeds?
To colonize large areas
-
What are the main ways that fruit is dispersed for colonization?
- 1. Fruit with black, blue or red colors are dispersed by birds and verterbrates
- 2. Fruits with hooked spines (burrs) are dispersed on animal fur or clothing
- 3. Squirrels and other mammals bury acorns or other nuts that may sprout
- 4. Fruits or maple, ash, and elm trees have "wings" that aid in wind dispersal
- 5. Orchids have dustlike seeds that are wind blown
- 6. Dandelions have seeds with parachutes that float on wind currents. Milkweeds, cottonwood trees, willows, goats beard, etc
- 7. Coconuts can float on water for dispersal to another island.
-
Fruits of which colors are disperse by birds and vertebrates?
Red, Black, Blue
-
___ have dustlike seeds that are wind blown
Orchids
-
What fruit floats on water to be dispersed on other islands?
Coconuts
-
Hesperidium:
Citrus fruit
-
Drupe:
Fruits with a single pit
-
Pomes:
- Apples and pears
- Parts of 5
- Members of the rose family
-
Most species of angiosperms use flowers to do what?
Attract pollinators and to reproduce
-
How do angiosperms use flowers to attract pollinators?
-
Nectaries
Flowers have ultraviolet landing strips for insects that guide them to the pollen
-
Are all flowers pollinated by pollinators?
No. Some are pollinated though wind-pollination
-
The angiosperm life cycle includes ____ fertilization
double
-
-
In angiosperms, the megaspores produce how many nuclei? Haploid or diploid?
8 haploid nuclei
-
Female gametophyte consists of embryo sac and the 8 nuclei in only___ cells.
in only seven cells
-
What is the most important part of the female gametophyte in angiosperm?
- The egg
- Two polar nuclei in the single cell
-
Pollen grains form a ____ toward the embryo sac after landing on the receptive stigma.
pollen tube
-
How many sperms pass through the pollen tube in the reproduction of angiosperm?
Two
-
Two sperm pass through the pollen tube during angiosperm fertilization. What does each do?
- One fuses with the egg to form the zygote
- Other fuses with polar bodis to form triploid endosperm nucleus
-
Where does the triploid endosperm nucleus come from in angiosperm reproductioin?
From the fusion of one out of two pollen sperms with the polar bodies in the female gametophyte.
-
What is the purpose of the triploid endosperm nucleus in angiosperm reproduction?
To nourish the embryo (kind of like the placenta in pregnant females)
|
|
