Chapter 38- reproduction of flowering plants Flashcards
Where does flower develop from?
They develop from floral bud.
What does the floral bud consists of?
it consists of apical meristem which give rise to reproductive organs.
what do we call the collection of petals?
We call them corolla
What do we call the collection of sepals?
We call them calyx
How many cells does the pollen grain have?
They have typically two celled male gametophyte contained in the wall of microspores
What are the two cells in pollen grain?
- large tube cell
2. small tube cell
What is the function of large tube cell?
- store protein and lipid for later stages.
2. they form the pollen tube
What is the function of small tube cell?
It is small generative cell that divide into two sperm after pollination.
what surround the pollen grain?
- pollen wall
2. pollen coat
What is the pollen wall made out of?
the pollen wall made out of a tough resistant biopolymer material called sporpolenin
What is the function of pollen coat?
it surround the wall of the pollen grain and it include lipid and protein to aid in the attachment to the stigma.
What are the 7 cells in the embryo sac?
- egg cell
- large central cell with 2 polar nuclei
- 3 antipodal cell
- 2 supportive synergids
What is pollination?
It is the delivery of pollen to the stigma of a pistil by wind or animal pollinator.
What is the process that causes the pollen tube to grow?
It is called tip growth.
What are the steps of pollen tube elongation?
- New cytoplasm and new cell material are added to the pollen tube by golgi vesicles.
- Plugs of the polysaccharides callose seals off older parts of the pollen tube.
What part determine if the pollen is compatible or not?
The stigma
What is endosperm?
it is rich in starch, protein, lipid, vitamins and minerals supplied by the parents sporophyte.
What does the endosperm feed or supply foods for?
it supplies nutritional needs for the developing embryo and often the young seedlings
What does the zygote divide into?
- small terminal cell which become embryo
2. large basal cell which become suspensor.
How does the early embryo get his food?
it gets its food directly by parents through the suspensor.
How does the old embryo get his food?
He get his food from endosperms
where does the seed coat develop from?
it develop form the integuments of the ovule. (sclereid cells)
What is the function of the seed coat?
- serves as water and oxygen barrier
2. shields embryo from UV radiation and microbial attack.
What is imbitition?
It is absorption of water to rehydrate and activate the embryo.
