B15.3 - Sexual Reproduction in Plants Flashcards
What is a carpel? [2]
- produces female gametes
- consists of stigma, style and ovary
What is a stigma? [1]
pollen grains attach to this end bit
What is a style? [1]
stalk that holds the stigma in the best position to receive pollen grains
What is an ovary? [2]
- contains female gametes inside ovules
- a hollow chamber that ovules develop from the walls of
What is a stamen? [2]
- produces male gametes
- consists of the anther and filament
What is a filament? [2]
- long stalk that holds the anther in the best position - to release pollen onto a visiting insect
What is an anther? [2]
- contains 4 pollen sacs filled with pollen grains
- each pollen grain contains a male nucleus
What is an ovule? [1]
develops from the walls of the ovary
What is a petal? [2]
- brightly coloured and scented to attract pollinating insects
- may produce nectar, a sugary solution, from small glands at their base
What is a sepal? [2]
- green and protect the flower bud
- usually disappear after pollination
What is pollination? [2]
the transfer of pollen grains from an anther to a stigma
When does fertilisation occur? [2]
when a pollen nucleus fuses with a nucleus in an ovule
Describe the petals of an insect pollinated flower. [1]
brightly coloured
Describe the anthers of an insect pollinated flower. [1]
stiff anthers inside the flower
Describe the pollen of an insect pollinated flower. [2]
- small amount
- very sticky
Describe the stigma of an insect pollinated flower. [1]
sticky to capture the pollen
Describe the petals of a wind pollinated flower. [1]
dull coloured
Describe the anthers of a wind pollinated flower. [2]
- anthers exposed out to disperse the pollen
- outside the flower to catch wind
Describe the pollen of a wind pollinated flower. [2]
- lots of smooth, light pollen is made
- can be easily blown by the wind
Describe the stigma of a wind pollinated flower. [1]
feathery and sticking out to catch pollen in air
Which type of pollination produces genetic variation? [1]
cross pollination
What is meant by the term Agents of Pollination? [2]
vectors that carry the pollen from the anther to the stigma
What are two main agents of pollination? [2]
- insects
- wind
What is fertilisation? [3]
when the nuclei of the male and female gamete (pollen and ovule in a plant) fuse together to form a zygote
What does the zygote become? [1]
the seed
What happens to the ovary wall? [2]
it swells and becomes the fruit
What environmental conditions are needed for germination? [3]
- water
- oxygen
- warm temperature
What does boiled water do in experiments? [1]
- removes any oxygen already present in the water
Why are multiple seeds used in each testtube for checking what conditions are needed for germination? [2]
- it might be dead
- lots of variation
