Plant reproduction Flashcards
(13 cards)
How do the stamens differ of wind vs insect pollinated flowers?
Insect - Enclosed within flower and stiff so they brush against insects
Wind - Exposed outside flower, long filaments to release pollen grain easily.
How do the stigmas differ of wind vs insect pollinated flowers?
Insect - enclosed within flower and sticky to catch pollen grains when insects brush past
Wind - Exposed outside of petals, feathery to catch airborne pollen grains
How do the petals differ of wind vs insect pollinated flowers?
Insect - large and brightly coloured to attract insects
Wind - Small and usually green
How do the nectaries differ of wind vs insect pollinated flowers?
Insect - Present. Nectar attracts insects.
Wind - Absent.
Describe how plants reproduce asexually using runners (natural method)
Plants grow side branches/stems along the ground that have small plantlets at the end.
Once they touch the soil, the runners grow roots, the plantlets grow and become Independant from the parent plant.
Describe how plants reproduce asexually using cuttings (artificial method)
Gardeners take cutting from healthy parent plants. A section of the parent plant with a new bud is cut off. Placed in water or soil to allow new roots to grow. Eventually grow into into adult plants (genetically identical to parent plant).
How does the pollen differ of wind vs insect pollinated flowers?
Insect - large size, sticky
Wind - large amounts, small size and light
Describe pollination, fertilisation and seed formation of a flower
Pollen grains deposited on stigma
Pollen grain grows a pollen tube down the style
Enzymes secreted at tip of tube digest the tissues of the style
Tube reaches ovule, male gamete travels through tube entering ovule through micropyle (small hole)
Male gamete fuses with female gamete (ovum) during fertilisation
Fertilised ovum divides by mitosis to form embryo
Ovule develops into seed
Ovary develops into fruit
What is the female gamete for plants and where is it produced?
Ova/ovum.
Produced in the ovules in the ovary of plant.
What is the male gamete for plants and where is it produced?
Pollen.
Produced in the anther.
What are the 3 things germinating plants need?
Warmth - Optimum temperature for enzymes to digest starch stores
Oxygen - Needed for aerobic respiration
Water - Provides a solution for enzymes and substrates so reactions can occur.
Describe how the embryo turns into a seedling during germination
Cotyledons surround the embryo, storing food for the seedling.
Water absorption splits the seed coat (testa) allowing the plumule and radicle to emerge
What is the purpose of cotyledons?
Store food for the seedling, providing it with energy until the plant can photosynthesise
