Post on 29-Dec-2015
Chapter 10/11 PLANT REPRODUCTION
P. 272
Growing Seasons:
1) annual- lives one
growing season.ex. petunia
ex. marigold
2) Biennials - lives two growing seasons.
Ex. Carrot(it reproduces in
the second year)- most herbaceous
stem plants are annuals or biennials.
3) Perennials - live year after year.
Ex. Maple tree, grass.
- usually woody stem plants.
- each year the stem grows wider and forms the annual growth ring.
- created by the cambium.
ANGIOSPERM REPRODUCTION
Flower Anatomy(p. 285)
1.Stamen
- the male part of the flower.Anther - contains
pollen grains.
Filament - thread-like structure that holds up the anther.
STAMEN- can you
identify which is the anther and the filament?
2) Pistil - the female part of the flower.
Stigma - covered with a sticky substance to capture pollen.
Style - the thin ‘neck’ to support the stigma.
Ovary - holds the ovules which turn into seeds after fertilization.
Which is the pistil?
Which is the stamen?
Sepals- leaves which protect
the developing petals.
Petals- protect the stamen
and pistil.- often colorful and
have an odor to attract insects for pollination.
Perfect Flowers
- have both male and female parts.
Imperfect Flowers
- has a pistil or a stamen - not not both.both.
- needs another needs another plant for plant for pollination.pollination.
Ex. cottonwood Ex. cottonwood treetree
ASSIGNMENT:Worksheet
“Seed Reproduction”
Pollination
- the transfer of pollen from an anther to a stigma.
Cross-pollination- pollen from a anther to a different plant’s stigma- by wind, insects.
Self-pollination
- when the stigma receives pollen from the anther of the same flower.
- must be a perfect flower
More Pollinators
Fertilization
- occurs after pollination.
- a pollen tube grows thru the style.
- The pollen (a male sperm cell) then fertilizes the ovule which turns into a seed.
Pollen tube example: Corn Pollen tube example: Corn “silk”“silk”
Fertilization
After pollination, the petals will fall off. Why?
Pollination has been completed. The petals are no longer needed.
After fertilization, the ovary develops into a fruit.
- it holds and protects the seeds.
Types of Fruit1) Fleshy
Ex. orange, tomato, cherry.
2) Dry
Ex. Beans, corn, peas, walnuts.
Seed Anatomy
Embryo
Seed Coat
Cotyledon
ASSIGNMENT:
WORKSHEET“FLOWER ANATOMY”
Seed Dissemination
- how seeds can be spread. (p. 289)
1) Carried by wind
- “winged” fruit
Ex. dandelions,
cottonwood
2) Carried by animals
Ex. Cockle burrs caught in fur.
3) Eaten by animals
- excreted with the waste.
PLANT PROCESSES
GAS EXCHANGE
- occurs in the leaf’s stomates.
- CO2 enters thru the stomate.
- O2 exits thru the stomate.
- necessary for photosynthesis.
Water vapor also escapes through the stomates.- called
transpirationtranspiration.
More transpiration….
PHOTOSYNTHESIS
- the process of turning light energy into food.
- the needed chemical is chlorophyll.- it traps sunlight.
- it also needs CO2 and H2O to make food and oxygen.
6CO2 + 6H2O + light C6H12O6 + 6O2
6 molecules of carbon dioxide and 6 molecules of water.
chlorophyll
One molecule of glucose and 6 molecules of oxygen.
C6H12O6 = glucose - a sugar which is used as energy or stored in roots and stems.
6CO2 + 6H2O + light C6H12O6 + 6O2
chlorophyll
The oxygen is mostly released as a waste.
- some is used to break down food.
Photosynthesis occurs in the chloroplasts located in the palisade layer of the leaf.
Importance of Photosynthesis
1. Provides food for almost all of the consumers on Earth.
2. Provides oxygen (90%) for organisms and removes carbon dioxide from the atmosphere.
RESPIRATION
- the process used to break down food into energy.
- it also occurs in plants.
C6H12O6 + 6O2 6CO2 + 6H2O + energy
- it occurs in the cell’s mitochondria.
- respiration’s energy is used to build and repair cells and tissues.
Photosynthesis’ and respiration’s raw materials are “linked together”:
Worksheet“Photosynthesis and Respiration”
PLANT RESPONSES
- the response of a plant to a stimulus is a tropism. p.312
1)Thigmotropism
- when touched, a plant ‘closes’ its leaves. (p. 311)
Ex. Venus Flytrap
ASSIGNMMENT:
WORKSHEET:
“PHOTOSYNTHESIS & RESPIRATION”
QUESTIONS
P. 296 8,13,17
P. 322 11,13,14,17
2) Phototropism- the plant grows towards light.
3) Geotropism or Gravitropism- the plant roots grow downward…- stems grow upward.- in response to gravity.
Tropisms are controlled by plant hormones called auxins.
Ex. for phototropism, the auxins move to the ‘shady’ side of the stem.- the auxins create more growth on that side causing the stem to bend into the light.
Photoperiodism- a flowering response
to the changes in the amount of daylight.
- plants need a certain amount of darkness to flower.
Long-day Plants- need short
nights to flower.
Ex. zinnias, potatoes
Day-neutral Plants- can flower
over a wide range of night lengths.
Ex. marigolds, corn.
Short-day Plants- need long
nights to flower.
Ex. poinsettia
Photoperiodism ensures there are lots of pollinators when the plant flowers - less ‘competition’.
ASSIGNMENT:
WORKSHEET“PLANT PROCESSES”
Seed Germination (p. 290)- when a seed sprouts.- conditions must be right
- moisture/warm temps.
- if not, the seed remains ‘dormant’ waiting for good conditions.
The plant uses the food stored in the cotyledon until photosynthesis can begin. (p. 291).
Asexual Reproduction
A) Natural- some plants produce “runners”.- where it touches the ground, a new plant is formed.
Ex. strawberry
- only one parent necessary.
B) Grafting
- attaching part of one plant to another.
Grafting is commonly done with trees - taking the best traits and combining them together.
Ex. orange tree
Very hardy
Sour fruit
Weak - intolerant
Sweet fruit
C) Water propagation
ASSIGNMENT:
WORKSHEET“CHAPTER REVIEW”