Plant reproduction-topic 5

• Pollination is the transfer of pollen from the anther of a stamen to the sigma of a carpel to allow for fertilisation to occur. Zygote is formed which conducts cell division to become an embryo. Occur by wind or pollinators
• fertilisation involves the fusion of a male and a femal gamete to form a zygote that undergoes cell division to develop into an embryo
• filament supports the anther
• Seed dispersal is the movement of seeds away from the parent plant once a seed is formed it needs to be dispersed away from the parent plant to avoid competition, if the seed has all the resources it needs then it will germinate and grow into a new plant
• plants need light, water, space, minerals in soil
• Endosperm is a glucose and mineral store which is surrounded by the cotyledon
• Sepal supports the flower
• Water seed dispersal, seeds are large have the ability to float, seeds float in ocean/river to a new area washed onto shore and start to grow e.g coconut
• Explosion seed dispersal, seeds are small and light the seed pod explodes and propelles seeds away from parent plant e.g exploding cucumber
• Animal seed dispersal (external) hooks to attach to fur seeds hook on to animals fur and fall off in a different location e.g burdock
• Animal seed dispersal (internal) seeds are encased in fruit which the animals eat and then expel in faeces e.g apples
• Stigma receives pollen during pollination
• Style supports the stigma
• Stamen is the male reproductive organ
• Anther produces pollen, male sex cell
• Petal is the attractive landing pad for insects
• Carpel is the female reproductive organ
• Male reproductive organ is the stamen female reproductive organ is the carpel male gamete is pollen and female gamete is ovule/egg
• wind seed dispersal seeds are light and adapted to fly seeds are blown away from the parent plant seed have a large SA e.g dandelion
• Asexual Reproduction, mitosis, 1 parent, no gametes involved, identical offspring, e.g bacteria and Komodo dragon, produces individuals without genetic variation, easy and quick and only 1 parent
• Sexual reproduction, meiosis, 2 parents, gametes involved, unique offspring, almost all plants+animals, lots of energy, time and 2 parents, species can adapt
• Germination is the development of an embryo in a seed into a young plant after seed dispersal
• Embryos which are germinating from seeds utilise the glucose and mineral resources stored in the endosperm, these resources are used until the plant grows leaves and is able to photosynthesis to generate glucose
• Asexual natural method, runners plant produces long stems which branch out from the plant, from these a new genetically identical clone of the parent is established
• Asexual artificial method, cuttings, propagation, humans remove parts of the plant which then has the ability to grow roots and become established
• Conditions required during germination are water (soften the seed coat) warmth (provides enzymes with kinetic energy) oxygen (reactant in respiration) plants need to respite to release energy for growth
• step 1 pollination pollen from the anther of a stamen moves between flowers by wind or animal
• Step 2 pollination pollen lands on The stigma of a carpel
• Step 3 pollination, pollen grows a pollen tube through the style, pollen tube curves goes round the ovaries
• Step 4 pollination the style provides the pollen with glucose needed for respiration to release energy in order to grow the cells
• Step 5 pollination this allows the nuclei of the gametes to come into contact with each other pollen+egg- zygote
• step 6 pollination the zygote develops into an embryo of a seed which gets dispersed
• Structure of a flowering plant

  
• Insect vs wind pollinated flowers