Plants: Angiosperms

Remember….. What is the group of flowering plants? In what structure is the plant embryo found which is made from a flower? What is the protective structure that surrounds a seed called? Angiosperms Seeds Fruits

A. Flowers 1. Flowers are organs of reproduction in angiosperms 2. Flowers contain male and female reproductive parts

3. Parts of a flower a. Sepals- kinds of leaf that protect the bud, can be green or brightly colored b. Petals- kinds of leaf inside the sepals, protect reproductive parts of a flower sometimes have brightly colored petals and nice smell to attract pollinators (exs. roses and lilies) sometimes white or green and no smell (exs. grasses)

c. Reproductive structures of a flower 1. Pistil (carpel)- female reproductive structure Usually one per flower, in the center contains stigma, style and ovary 2.Stamen- male reproductive structure Usually several per flower, around the pistil (carpel) Contains anther and filament

4. Types of flowers a. Perfect flowers- both male and female parts, stamen and pistil/carpel Ex lily b. Imperfect flowers- only male (stamen) OR female (pistil/carpel) parts but not both Ex zucchini

B. Reproduction with Flowers Seeds and Fruits

Stamen: Male reproductive Structure 1. Stamen- contains anthers and filaments a. Filament- stalk that holds anther b. Anther- produces pollen grains which contain plant sperm, pollen released when it bursts open

Pistil/Carpel: Female Reproductive Structure 2. Pistil/carpel contains stigma, style and ovary a. Stigma- sticky top that catches pollen b. Style- tube that connects stigma to ovary c. Ovary- bottom of pistil that contains ovules with eggs inside Ovary

Pollination 3. Pollination- movement of pollen from anther of stamen to stigma of pistil/carpel Can occur by wind, insects, bats, birds, and water

Pollination a. Self pollination- pollen travels from anther of stamen of a flower and lands on stigma of pistil of SAME flower, or on different flower on SAME plant, must be perfect b. Cross pollination-pollen travels from stamen of a flower to pistil of another flower on a DIFFERENT but similar plant, flowers can be perfect or imperfect

Self pollination vs Cross pollination Same Plant Different Plants

Fertilization 4. Fertilization- as part of sexual reproduction it is the joining of the nuclei of male (sperm) and female (egg) sex cells of flowers Takes place inside the pistil

Steps of pollination and Fertilization a. Pollen grain from anther of stamen lands on stigma of pistil b. One cell from pollen forms a pollen tube from stigma through style to ovary c. Other cell from pollen is called sperm & moves through pollen tube to ovule of ovary where egg is d. Nuclei of sperm and egg join (fertilze) to form a zygote e. Fertilzed egg develops into a seed f. Seed contains an embryo,or baby plant, plus a cotyledon (endosperm)

seed embryo

5. Seeds and fruits a. Seeds- formed from mature (eggs in) ovules b. Fruits- from mature ovary, form around seeds to protect them c. Name some plants that have fruits. All angiosperms have fruits

C. Parts of a seed and germination

1. Seed parts a. Seed coat- protects the embryo b. Cotyledon- inside seed, used to absorb food from endosperm of seed for developing plant embryo Monocots (1 cotyledon) vs dicots (2 cotyledons)

Seed parts c. Embryo- baby plant; has tiny root, stem and cotyledons (develop into leaves) d. Hilum- scar where seed was attached to ovary of flower

2. Germination of seeds Germination- development of embryo inside seed into a new plant with good soil and water

3. Seed dispersal Seed dispersal- Movement of seeds for germination By wind, water, animals eating fruits and depositing seeds or carrying seeds on fur

D. Asexual reproduction in plants

Asexual reproduction 1. Asexual Reproduction involves one parent Offspring are genetically identical to their parents

Types of Asexual Reproduction Vegatative propagation- asexual reproduction that uses plant parts to grow new plants Runners- underground stems Tubers- “buds or eyes” part of underground stems Spores- airborne particles stored in spore cases Bulbs- leafy, underground stems Cuttings- root, leaf or stem pieces

Tubers Exs potatoes, yams Cuttings- asparagus roots bulbs runners

E. Tropisms

Tropisms/Plant Responses Tropism- growth response to a stimulus, (usually by growing in a certain direction) Stimulus- a change that causes response Ex: light, touch, gravity or water

5. Types of tropisms & Positive Vs Negative Tropisms

Positive Tropism Negative Tropism Growth toward the stimulus Growth away from the stimulus

a. Phototropism Plant’s growth in response to light Leaves and stems grow towards light

b. Gravitropism Plant’s growth in response to gravity Roots grow towards gravity and stems grow away from it

c. Hydrotropism Plant’s growth in response to water Roots grow towards water

d. Thigmotropism Plant’s growth in response to touch stems grow due to touch, grow around a structure Example: poison ivy