Plant ReproductionFlowers

Functions of Flower Parts 1Petal-

Petals are used to attract insects into the flower, they may have guidelines on them and be scented.

Stigma-

Is covered in a sticky substance that the pollen grains will adhere to.

Style-

The style raises the stigma away from the Ovary to decrease the likelihood of pollen contamination. It varies in length.

Ovary-

This protects the ovule and once fertilization has taken place it will become the fruit.

Ovule-

The Ovule is like the egg in animals and once fertilization has taken place will become the seed.

Receptacle-

This is the flower's attachment to the stalk and in some cases becomes part of the fruit after fertilization e.g. strawberry.

Functions of Flower Parts 2Flower stalk-

Gives support to the flower and elevates the flower for the insects.

Nectary-

This is where a sugary solution called nectar is held to attract insects.

Sepal-

Sepals protect the flower whilst the flower is developing from a bud.

Filament-

This is the stalk of the Anther.

Anther-

The Anthers contain pollen sacs.

The sacs release pollen on to the outside of the anthers that brush against insects on entering the flowers.

Once the pollen is deposited on the insect.it is transferred to the stigma of another flower.

The ovule is then able to be fertilized.

2 Types of flowers: Perfect vs. Imperfect

Imperfecta flower that has

either all male parts or all female parts

EX: cucumbers, pumpkin, and melons

Perfecta flower that has

both male and female parts in the same flower

EX: roses, lilies, and dandelions

Anther splits open when the pollen are mature

Pollen is carried to the stigma by wind, water, or animals. THIS is pollination

Plant reproduction is most successful when pollination rates are high

Pollination is part of -Sexual reproduction, which results

in greater genetic diversity (good for the species survival)

Pollination

Pollination VectorsWind Pollination: Dull, scentless flowers with reduced petalsBees/Butterfly Pollination: Bright color, nectaries, scent. They sip nectar, get pollen on coats, transfer pollen from flower to flower

Bird Pollination: Nectaries, brightcolors, tube-like flowersMoth Pollination: White petals, open at nightFly Pollination:Rank odor, fleshcolored petals

Pollen is carried to the stigma in pollination

A pollen grain grows a tube down the style to the ovary

Two sperm travel down the tubeIn a process called double

fertilization, one of the sperm fertilizes the egg and the other unites with the central cell, forming an endosperm (which becomes food storage tissue)

IS THE UNITING OF THE SPERM AND EGG NUCLEI, CREATING A ZYGOTE.

Fertilization

Following fertilization, the ovary develops into a fruit with seeds inside, while the rest of the flower dies

Fruits help protect the seeds until they mature and help scatter seeds into new habitats

-Fruits are the part of the plant that contains seeds: cucumbers, maple “helicopters”, green peppers, squash are all fruits.

Fruits and Seeds

One or two cotyledons forms, which form leaves that will be used by the germinating seedling.

Food is derived from the endosperm

Thus, the seed is an undeveloped plant embryo with stored food and protective coats

At maturity, seed coat dries and hardens, enabling it to survive harsh conditions

Once conditions are favorable, seed germinates (develops into an embryo) and grows into a new plant.

Germination