Sexual Reproduction In Plants Flashcards
What is the female reproductive organ in plants?
The carpel :
Style - supports stigma
Stigma - sticky surface where pollen grains land on
Ovary- the site of meiosis where female gametes are produced
Ovule - contains the female gametes
What is the carpel made up of ?
Style
Stigma
Ovary
Ovules
What is the carpel
The female reproductive organ of a plant
What is the stigma ?
Sticky surface where pollen grains land on
What is the ovary in a plant ?
Site of meiosis where female gametes are produced
Waht is the function of the ovule ?
Contains the female gametes
What is the male reproductive organ of a plant
The stamen :
Filament
Anther
What does the stamen consist of ?
Filament And Anther
What is the filament ?
Stalk that supports anther
Contains vascular tissue to carry WATER AND NUTRIENTS-(sucrose mineral ions) to the anther containing the developing pollen grains
What is the style ?
Tube/ stalk like structure that connects the stigma to the ovary
What is the anther ?
Produce and contains the pollen grains
What is the calyx ?
Outer most ring of the flower
Made up of the sepals
Usually green protect the flower while its still forming the bud
What is the corolla?
On the inside of the sepal- layer/ ring of modified leaves -petals
Can range from absent to small pale green to large and brightly coloured to attracts insects
What is the receptacle ?
Top of stalk from high parts of flower develop
What are nectaries?
May be present at base of stamens
Secrete sweet substance - nectar
Nectar attracts insects that carry pollen from one flower to another
Can also attracts animals (e.g) mice ,hummingbirds and bats
What is the peduncle ?
The stem
The peduncle is the last internode of the main stem of a plant- contains vascular tissue
What are the 4 sets of modified leaves that arise for m the receptacle?
Calyx- outermost
Corolla
Stamens
Carpels-innermost
What is the male reproductive cells and where is it produced?
Pollen grains
In the anther
What is the female reproductive cells and where is it produced ?
Embryo sac
In the ovules of the ovary
What is absent in wind-pollinated flowers?
Petals, scent, and nectaries are absent.
These features are typically present in insect-pollinated flowers.
How are the anthers and stigma positioned in wind-pollinated flowers?
The anthers and stigma hang outside the flower.
This allows pollen to be shed easily into the air.
What adaptations do wind-pollinated flowers have for pollen dispersal?
Anthers are loosely attached and stigmas are usually feathery.
This increases the chance of pollen being dispersed and collected.
What is the size and weight of pollen in wind-pollinated flowers?
Pollen is usually small and light, sometimes with air sacs.
These adaptations help the pollen stay airborne longer.
Why do wind-pollinated flowers produce large quantities of pollen?
To increase the chance of pollen landing on a stigma of the correct species.
This strategy compensates for the randomness of wind dispersal.
Which type of plants are the most common wind-pollinated flowers?
Grasses are the most common wind-pollinated flowers.
They are well adapted to wind pollination.
