Flowering Plant Sex

PetalsStigma

Anther

FilamentOvary

Sepals

OvulesNectaries

Style

Label your diagram on your worksheet

Carpel

female parts

Stamen male parts

What do the parts do?

Sepals- protect the flower when it is a bud

Petals- colourful to attract the insects

Nectaries- give out sugary liquid to attract insects

Stamen- anther produces male sex cells (pollen)

Carpel- stigma traps pollen

Style is where pollen tube grows down to female sex cells.

Carpel- ovary produces female sex cells (ovules)

Add these notes into your table on your worksheet

Pollination

• Pollination involves the transfer of pollen (male gamete) from the anther to the stigma (outermost female part)

• If it is in the same flower it is calledself-pollination.

• If between different flowers it is calledcross-pollination

• Plants are pollinated by insects, wind, birds or animals

Pollination

Pollination

Sexual reproduction in flowers

Sexual reproduction in flowers

Fertilisation

• Fertilisation involves the fusion of the nucleus of the male gamete (in the pollen) with the nucleus of the female gamete (in the ovules).

Fertilisation

• The pollen grain grows a tube.• The tube reaches an ovule.• The gamete nuclei fuse (fertilisation)

and a zygote (seed) forms.

Let´s have a look at some pollen tubes underneath the microscope!

Fertilisation

Fertilisation

Once fertilisation has taken place the zygote (fertilised ovule)becomes a seed, and the ovary becomes a fruit.The petals die and fall off.The plant seeds are in the fruit.

Fruit Formation and Seed Dispersal

Seeds must be carried away (dispersed / scattered) from the parent plant to:• Reduce overcrowding

Seed Dispersal- why?

• Reduce competition for:- Water- Light- Nutrients

Learning about Seed Dispersal

Use the next few slides, the Blog link and the video clip to help you fill in the rest of your worksheet

relating to seed dispersal

A wee introduction to seed dispersal!