Notes 8 Flashcards
The 3 Fs of angiosperm sex are what?
Flowers, fruits, and double fertilization
The male parts of the plant are called ____ and are made of the ___ and the ___.
Stamen, anther and filament.
The stamen produces 4 _____?
microsporangium or pollen sacs.
Each microsporangium has many diploid cells called ____?
microsporocytes (microspore mother cells)
Microsporocytes then undergo ___ to form 4 ___ microspores
Meiosis, haploid.
Each microspore undergoes unequal ____ to become a ___ male gametophyte (pollen grain).
Mitosis, haploid.
The male gametophyte is made of 2 cells, a ____ and a -______.
Smaller generative cell and larger tube cell.
The smaller genertaive cell and larger tube cell of the male gametophyte + a spore wall=??
A pollen grain
The female parts of the plant are called the ___ and are made of the ___, ____ and ___.
Carpel, stigma, style, ovary
The ____ is the container in which seeds are enclosed and contains one or more ____ in the _____ (base of the carpel).
Carpel, ovules in the ovary.
What is the tissue in which the embryo sac (female gametophyte) forms?
Megasporangium.
What are the 2 layers of practice tissue that surround the megasporangium called?
Integuments
The integuments will develop the seed coat with a gap called the _____.
Micropyle
One cell in each megasporangium (ovary) is known as the what?
Megasporocyte
The megasporocyte enlarges and undergoes meiosis to become 4 _____ _______.
Haploid megaspores.
Of the 4 megaspores that are developed, how many survive?
One survives the other 3 degenerate
The megaspore that surives divides by ______ without _____ to create a large cell with ___ ____ nuclei.
The surviving megaspore nucleus divides by mitosis without cytokinesis which creates a large cell with 8 haploid nuclei.
The large cell with 8 nuclei divides by membranes to form what?
The embryonic sac
In the female gametophyte, at the micropyle end, what 2 cells flank the egg and help guide the male gametophyte (pollen tube) to the embryo sac?
Synergid cells
Where are polar nuclei?
Polar nuclei are not in cells but in the cytoplasm of the large central cell.
Female gametophyte (ovule) has ___ nuclei within __ cells and an embryo sac enclosed by the megasporangium and __ integuments.
8,7,2
When a pollen grain lands on the sticky stigma end, the tube cell does what?
The tube cell elongates to form a pollen tube which travels down the style to the ovary.
While travelling down the generative cells divide by mitosis to form 2 ___ that travel down the tube to the micropyle which is guided by chemicals from the ____.
sperm, synergid cells
One sperm fertilize the egg=?
zygote
One sperm combines with 2 polar nuclei forming a triploid (3n) nucleus= ?
endosperm. This is what is meant by double fertilization
Whats the purpose of an endosperm?
Endosperm nourishes seed until it can create its own food.
After fertilization the ovule develops into a ____ (embryo and endosperm) and the ovary develops into a _____.
seed, fruit.
The fertilized egg (zygote) splits via mitosis to form a -____ cell and ____ cell.
basal cell and a terminal cell
What can be credited to giving rise to majority of the embryo?
Terminal cell gives rise to most of the embryo.
The basal cell divides into a thread of cells called what? What is its purpose?
The basal cell divides into a thread of cells (suspensor) which anchor the embryo to the parent and help transfer nutrients from the parent to the embryo. In some plants the suspensor becomes the endosperm.
The terminal cell divides to form what?
Terminal cell divides to form a proembryo: cotyledons form as bumps on the proembryo. A root apex forms at the opposite end.
Seeds are adapted to stay dormant until conditions are what?
Optimal for germination.
