Flowers, Seeds, and Tech Flashcards
Difference between complete and incomplete flowers
Complete flowers have all “organs”. Incomplete flowers do not
Whether not flowers are complete or incomplete depends on what?
what pollinators they are trying to attract
Pollen is located where?
in anthers
Microsporocytes undergo _______ to make _ ___________.
meiosis; 4 microspores
Microspores become a _______ _____.
pollen grain
Describe a pollen grain
gametophyte with a spore wall, generative cell (divides into 2 sperm), and tube cell
What is a tube grain
What the tube cell of a pollen grain grows into
Embryo sacs are found where?
ovules
Megasporocytes undergo ______ to form _ ____________.
meiosis; 4 megaspores
Describe the embryo sac
gametophyte with an integument (tough outer layer), egg cell, and two polar nuclei in a central cell
First step of pollination
Transfer of pollen to the stigma
When pollen reaches the stigma, what happens?
Pollen germinates and extends a pollen tube
What does the pollen tube do after extending?
sends two sperm to the embryo sac (double fertilization)
In pollination, one sperm fertilizes the egg forming a _____.
zygote
Describe the endosperm
when the other sperm fertilizes the polar cell and it becomes triploid nutritive tissue
What are the 4 pollination strategies?
colors of flowers, scents, nectar, mimicry
Ways flowers are colored to attract pollinators?
bright, white (night moths), UV
Way flowers are scented to attract pollinators?
sweet (bees), stinky (flies)
Pollinators flowers attract with nectar?
bats, birds, and the bees
Ways flowers use mimicry to attract pollinators?
fake mates (wasps)
________ plants have either male or female flowers to prevent self pollination.
Dioecious
________ flowers only contain stamen to prevent self pollination.
Staminate
_______ flowers only contain carpels to prevent self pollination.
Carpellate
What does it mean when plants stagger their organs?
their stamen and styles are at different heights to prevent self pollination
______ flowers have long stamens and short styles.
Thrums
___ flowers have short stamens and long styles.
Pin
Most plants reject their own pollen. This is called what?
Self incompatibility
______ become fruit to protect and disperse seeds.
Ovaries
What is the pericarp?
When the ovary wall becomes the thickened wall of the fruit called
Sometimes after the pericarp is formed, what happens to the plant?
other organs fall off
Describe simple fruit with example
from one carpel or carpels fused into one (pea pod)
Describe aggregate fruit with examples
from multiple carpels on one flower (strawberry, blackberry)
Describe multiple fruit with examples
carpels from many flowers come together (pineapple, figs)
Describe accessory fruit with example
made from tissues besides the ovary usually the fleshy tissue in the ovary called the receptacle. (apple)
Fruits ripen when?
when seeds are fully developed
Define integument?
a tough outer protective layer
Covering from integument (name this part in seed development)
seed coating
Seed leafs, used for nutrient (name this part in seed development)
Cotyledon
Just below the cotyledons (name this part in seed development)
Epicotyl
What does epicotyl hold?
holds mini leafs and apical meristem
What is the radicle
embryonic root
The hypocotyl is located where
just below the epicotyl attached to the radicle
Name 4 methods of seed dispersal
- Eaten by animals & passed thru digestive tract
- Carried by wind
- Float in water
- Some have hooks to catch fur or feathers
What is the first step of germination?
Imbibition
Describe imbibition
uptake of water by seed
______ breaks through first in germination.
Radicle
After the radicle breaks through, what happens in germination?
The hypocotyle then straightens out raising the cotyledons and epicotyl
After the cotyledons and epicotyl are straightened out, what happens in germination?
The epicotyl spreads the mini leaves
When plants grow through fragmentation, what grows a where the plant is clipped
a callus
Define callus
group of undifferentiated dividing cells
Asexual seed production is called what?
Apomixis
Two related plants can be combined or ______.
grafted
In grafting, a _____ is placed on a ____.
shoot; root
In grafting, the root is the ____ and the shoot is the _____.
stock; scion
What does transgenic means?
plants having genes inserted to promote new phenotypes
Give examples of transgenic use
- bacterium DNA that makes a chemical toxic to insects but theoretically harmless to people
- inserting Daffodil genes into rice to increase beta carotene
