Plant ReproductionPlant Reproduction

How do plants reproduceHow do plants reproduce

►There are two kinds of ways that There are two kinds of ways that plants reproduce. Do you know what plants reproduce. Do you know what they are???they are???

►The two ways are sexual reproduction The two ways are sexual reproduction and asexual reproduction.and asexual reproduction.

►What is the difference between the What is the difference between the two????two????

Sexual Reproduction in Sexual Reproduction in PlantsPlants► Sexual reproduction in plants is the production of seeds.Sexual reproduction in plants is the production of seeds.

► Producing seeds requires combining a pollen grain and Producing seeds requires combining a pollen grain and ovum (egg).ovum (egg). This combines genes from 2 different parents and causes the This combines genes from 2 different parents and causes the

plants to be genetically different.plants to be genetically different. What are some benefits of genetic variation????What are some benefits of genetic variation????

► Sexual reproduction in seed plants usually involves Sexual reproduction in seed plants usually involves flowers.flowers. What function do the flowers serve?????What function do the flowers serve?????

► There are other ways that plants reproduce sexually There are other ways that plants reproduce sexually that don’t involve flowers but they work in similar ways.that don’t involve flowers but they work in similar ways. Pine trees use cones to reproduce. The cones are both male Pine trees use cones to reproduce. The cones are both male

and female and serve the same purpose as flowers.and female and serve the same purpose as flowers.

Did you know??? That most flowers have both male and female parts on the same flower, and often they are capable of fertilizing themselves.

Plant life cycle: Sexual Plant life cycle: Sexual reproductionreproduction

►A plant starts out as a pollen grain and A plant starts out as a pollen grain and an unfertilized egg.an unfertilized egg.

►This produces a seed through the This produces a seed through the process of fertilization.process of fertilization.

►When the seed settles it grows into a When the seed settles it grows into a seedling.seedling.

►The seedling grows into a mature plant The seedling grows into a mature plant which is capable of producing more which is capable of producing more pollen and eggs, which grow new pollen and eggs, which grow new plants.plants.

The process of fertilizationThe process of fertilization

Parts of a FlowerParts of a Flower► The Stamen is the male reproductive part of the The Stamen is the male reproductive part of the

flower. It contains the pollen.flower. It contains the pollen.► Pollen is responsible for fertilizing the ovum (egg).Pollen is responsible for fertilizing the ovum (egg).► The Pistil is the female reproductive organ.The Pistil is the female reproductive organ.

At the base of the pistil is the ovary, which contains the At the base of the pistil is the ovary, which contains the ovum.ovum.

► Pollen travels down the stigma where it meets the Pollen travels down the stigma where it meets the ovum (egg) and fertilizes it.ovum (egg) and fertilizes it.

► Once the ovum is fertilized the plant concentrates its Once the ovum is fertilized the plant concentrates its energy on producing a seed.energy on producing a seed. The seed must have high energy stores so that the embryo The seed must have high energy stores so that the embryo

inside it can grow until it is developed enough to produce its inside it can grow until it is developed enough to produce its own food.own food.

That is why nuts are so high in energy.That is why nuts are so high in energy.Question: What is the function of the petals on the flower????

Answer: The petals may have more than one function, but the most common function is to attract insects and animals that will move pollen and fertilize the plants.

Pollen and pollinationPollen and pollination

►As we said before pollen is what fertilizes As we said before pollen is what fertilizes the ovum.the ovum.

►Pollination is the process of fertilization.Pollination is the process of fertilization.►Pollinators are the organisms Pollinators are the organisms

(birds/insects) that help in the process of (birds/insects) that help in the process of fertilization.fertilization. Hummingbirds, bees, and other insects get Hummingbirds, bees, and other insects get

pollen stuck to them when they are collecting pollen stuck to them when they are collecting nectar. When the move to the next flower nectar. When the move to the next flower some of the pollen will fall off and fertilize the some of the pollen will fall off and fertilize the that flower. that flower.

Seed distributionSeed distribution► Seeds are dispersed in a number of different Seeds are dispersed in a number of different

ways. How many can you think of????ways. How many can you think of???? Some seeds are dispersed by the wind, like Some seeds are dispersed by the wind, like

dandelions.dandelions. Some fall to the ground and grow only where they Some fall to the ground and grow only where they

fall.fall. Some are eaten by animals and when the animals Some are eaten by animals and when the animals

pass them they are dropped in the soil.pass them they are dropped in the soil. Some seeds stick to the fur of animals and are Some seeds stick to the fur of animals and are

dropped in other places. You’ve probably had these dropped in other places. You’ve probably had these types of seeds stuck to your shoelaces when you types of seeds stuck to your shoelaces when you walk through the forest.walk through the forest.

What is Asexual What is Asexual reproduction???reproduction???

►Asexual reproduction is the process of Asexual reproduction is the process of reproduction which only one parent is reproduction which only one parent is requiredrequired Asexual reproduction in plants is also Asexual reproduction in plants is also

known as vegetative reproduction.known as vegetative reproduction. Asexual reproduction creates plants that Asexual reproduction creates plants that

are genetically identical to one another.are genetically identical to one another.

Questions: What are the advantages and disadvantages of creating genetically identical plants???

What ways do you know of that plants reproduce asexually????

Types of Vegetative Types of Vegetative reproductionreproduction

► Runners: Runners are long stems that grow Runners: Runners are long stems that grow along the surface of the soil. Eventually along the surface of the soil. Eventually they will grow into a new plant.they will grow into a new plant.

► Rhizomes: Stems that run underground and Rhizomes: Stems that run underground and sprout new plants.sprout new plants.

► Suckers: Roots from the parent plant that Suckers: Roots from the parent plant that produce new plants.produce new plants.

► Cuttings: When you cut the stem of a plant Cuttings: When you cut the stem of a plant and put the stem into a good growing and put the stem into a good growing medium (soil, water) the cutting can medium (soil, water) the cutting can produce new roots and continue to grow.produce new roots and continue to grow.

GraftingGrafting►Grafting is another form of asexual Grafting is another form of asexual

reproduction.reproduction. Grafting is when a cutting from one plant is Grafting is when a cutting from one plant is

inserted into the stem of a different plant.inserted into the stem of a different plant. The cutting uses the other plants root The cutting uses the other plants root

systems to grow the cutting.systems to grow the cutting. This means that you could potentially have This means that you could potentially have

and apple tree that grows three different and apple tree that grows three different types of apples.types of apples.

One example of how grafting is One example of how grafting is donedone