Download Parts of the Flower

Chapter 4 Lesson 3 Notes
How do plants reproduce?
Parts of the Flower
 stamen-male part of flower
 Pollen-a grainy, often yellow powder, made of tissue at the top of each
stamen
 Pistil-female part of flower
 Flowers with only ONE of these parts=imperfect flower
 Flowers with BOTH parts=perfect flower
Composite Flowers
 One flower made up of hundreds of little flowers (ex.  sunflower)
Passing Information
 If a species did not reproduce, it would soon become extinct
 Sexual reproduction is the passing of DNA from two parents to their
offspring. In plants, flowers are the organs where sexual reproduction takes
place.
Pollination
 Pollination-moving pollen from the stamen to the pistil
 ways in which pollination happens:
o Wind
o Water
o Insects, bats and birds going from flower to flower
 Fertilization is the FIRST STEP in the life of a new plant
Combining DNA
 The young plant will grow to look much like the parents.
o It will NOT ALWAYS look like the parent. Example: when pollen
from a plant with red flowers pollinates a plant with white flowers, the
offspring may be a plant with pink flowers.
Going to Seed
 A seeds three main parts:
o The seed coat-has two jobs
 Protects new plant called embryo
 Guards a stash of stored food called endosperm
o Embryo-has structures called seed leaves (cotyledons)
o Endosperm
Spreading Seeds
 In some plants, seeds plop on the ground and begin to sprout.
 Animals may spread seeds that are inside tasty fruit (ex.-berries)
 Once the seed is moved from the parent plant, the embryo (new plant) will
stay in the seed until conditions are right (temperature/moisture)...can’t wait
too long, or embryo will die
Spores
 Mosses and ferns are plants that do not make flowers.
 Spore-a single plant cell that can develop into a new plant
 Similar to seeds:
o Stored food
o Some are covered with a protective wall
 some spores can wait a long time for the right conditions before they start to
grow
Reproducing Without Seeds
 reproduce without sperm cells and egg cells  asexual reproduction  one
parent
o one parent is giving all the genetic information
 new plant normally has same genes as parent
Runners and Budding
 Many plants can reproduce asexually (one parent) by growing new plants
from their stems or roots. (ex. Spider plants, strawberries, many types of
grass)

All of these plants can ALSO reproduce with seeds
 Plants can also reproduce by budding (little buds form on the plant and drop
of to grow as separate plants)