Scribe Post 3/13/12

Today in class we:
- Watered and Measured the plants
- Took a Ch.16 Quiz
- Finished Ch.28 Notes

Homework:
- Complete Ch.28 Study Guide due 3/19
- UP pg.41-54 due 3/19
- UP pg.19-34 read and prep lab for tom.
- Wildland project
- Ch.28 Quiz Tuesday 3/20
- BRING TEXTBOOK TOMORROW!

Plant Reproduction

This diagram shows the reproductive process of the male gametophyte (pollen) and the female gametophyte (embryo inside an ovule).

Process of Double Fertilization



The 2 diagrams above show the 4 steps to Double fertilization:
1. Pollination
- A pollen grain sticks to the stigma and germinates then,
- it travels down the pollen tube and stops midway to:
2. Form into 2 sperms
3. Travels rest of the way through the pollen tube to the ovule
4. Double fertilization occurs
- the first sperm fertilizes the egg, forming a normal 2n zygote.
- the second sperm fertilizes two polar bodies to form 3n or the tripod central wall, which later becomes the endosperm that nourishes the embryo.

Seed Formation

-Cotyledons are organs that absorb nutrients from endosperm for the developing embryo
-Embryos develop a tough protective seed coat when mature
-The seed stays dormant until environmental conditions are favorable

Fruit Formation

Fruit= mature ovary

Seed Germination


-The seed coat ruptures as it expands with water
- The embryos' roots emerge first then its' shoots which from a hook to protect it
- The plants' leaves starts to expand and photosynthesize
- Only a small number of seedlings are able to reproduce

Plant Growth
- Some plants have indeterminate growth with means that plants can continue to grow as long as they live
- They have a finite life span
- Annuals mature and reproduce and die all in 1 season Ex.) wheat, corn, rice, impatients
- Biennials grow in the 1st year and reproduce during the second year Ex.) carrots
- Perennials live and reproduce for many years Ex.) trees, shrubs, some grasses
Primary Growth= lengthening
Meristem- are cells that divide to create new cells and tissues
Secondary Growth= thickening
wood= dead tissue
Vascular cambium- generates secondary xylem and phloem. Secondary xylem produced each year gives the thickness of perennial plants and wood= annual growth of rings
Cork cambium protects the stem when the plants' mature, then it dies.
Everything outside the vascular cambium: secondary phloem, cork cambium, cork = bark

Pollinators and flowers have a mutual symbiotic relationship
Flower benefit through seed dispersal and pollination
Pollinators benefit through nectar and pollen for food
Color and fragrance attract the pollinators
Birds see red/pink
Bees use smell

Sincerely,
Nazia

NEXT SCRIBE POST: ***Michael***

Scribe Post 3/13/12

Today in class we:
- Watered and Measured the plants
- Took a Ch.16 Quiz
- Finished Ch.28 Notes

Homework:
- Complete Ch.28 Study Guide due 3/19
- UP pg.41-54 due 3/19
- UP pg.19-34 read and prep lab for tom.
- Wildland project
- Ch.28 Quiz Tuesday 3/20
- BRING TEXTBOOK TOMORROW!

Plant Reproduction

This diagram shows the reproductive process of the male gametophyte (pollen) and the female gametophyte (embryo inside an ovule).

Process of Double Fertilization


There are 4 steps to Double fertilization:
1. Pollination
- A pollen grain sticks to the stigma and germinates then,
- it travels down the pollen tube and stops midway to:
2. Form into 2 sperms
3. Travels rest of the way through the pollen tube to the ovule
4. Double fertilization occurs
- the first sperm fertilizes the egg, forming a normal 2n zygote.
- the second sperm fertilizes two polar bodies to form 3n or the tripod central wall, which later becomes the endosperm that nourishes the embryo.

Seed Formation
-Cotyledons are organs that absorb nutrients from endosperm for the developing embryo
-Embryos develop a tough protective seed coat when mature
-The seed stays dormant until environmental conditions are favorable


Fruit Formation

Fruit= mature ovary

Seed Germination

-The seed coat ruptures as it expands with water
- The embryos' roots emerge first then its' shoots which from a hook to protect it
- The plants' leaves starts to expand and photosynthesize
- Only a small number of seedlings are able to reproduce

Plant Growth
- Some plants have indeterminate growth with means that plants can continue to grow as long as they live
- They have a finite life span
- Annuals mature and reproduce and die all in 1 season Ex.) wheat, corn, rice, impatients
- Biennials grow in the 1st year and reproduce during the second year Ex.) carrots
- Perennials live and reproduce for many years Ex.) trees, shrubs, some grasses
Primary Growth= lengthening
Meristem- are cells that divide to create new cells and tissues
Secondary Growth= thickening
wood= dead tissue
Vascular cambium- generates secondary xylem and phloem. Secondary xylem produced each year gives the thickness of perennial plants and wood= annual growth of rings
Cork cambium protects the stem when the plants' mature, then it dies.
Everything outside the vascular cambium: secondary phloem, cork cambium, cork = bark

Pollinators and flowers have a mutual symbiotic relationship
Flower benefit through seed dispersal and pollination
Pollinators benefit through nectar and pollen for food
Color and fragrance attract the pollinators
Birds see red/pink
Bees use smell

Sincerely,
Nazia

NEXT SCRIBE POST: ***Michael***

Scribe Post 3-12-12

Today in Class We:

~Watered and Measured Fast Plants

~Notes (Ch. 28: Flowering Plants)

Know Monocots vs. Dicots for Lab!!

*Memorize these characteristics below*

Roots: Root hairs-increase

surface area of root for

absorption.

Large taproots - store food

such as starch for plant (Ex:

carrots, turnips, sugar beets,

sweet potatoes................................Monocot Root --->

<--- Dicot Root

.................................................................................................................................

Stems - Terminal bud is at apex of stem

when plant stem is growing in length.

Axillary buds, in angle formed by a leaf

(and stem) are dormant.

Terminal bud produces hormones

inhibiting growth of axillary buds = apical

dominance, so plant can grow up to sun.

Axillary buds begin growing and develop

into branches under certain conditions.

Types of Stems

Runner in a strawberry plant = horizontal

stem - new plants emerge from tip of

runner = asexual reproduction

Rhizome of an iris plant =horizontal

underground stems = store food, & can

bud new plants

Tubers are rhizomes ending in enlarged

structures (potatoes). Eyes of potato are

axillary buds, can grow when planted.

Leaves - flat blades (for light collection) and

petioles (joins leaf to stem.) Celery is a big

petiole.

Tendrils = modified leaves for climbing

and support .

Spines of a cactus = modified leaf parts

protecting plant. Cactus stem is

photosynthetic.

2 Plant Vascular Tissues:

1. Xylem - contains water conducting cells -

move water & minerals up stem

2. Phloem -contains food conducting cells -

transport sugars from leaves or storage tissue

to other parts of plant

3 Tissue Systems continuous throughout

plant:

1. Dermal-covers, protects, waxy coating

(epidermis)

2. Vascular- xylem and phloem; support,

transport

3. Ground - bulk of young plant, fills spaces

between epidermis and vascular.

Photosynthesis, storage, support.

Types of ground tissue:

Cortex - in root,cells store food, take up

water & minerals.

Endodermis - selective barrier in cortexdetermines which substances pass between

cortex and vascular tissue.

Pith - fills center of stem in dicots, food

storage.

***NEXT SCRIBE**: NAZIA

Scribe Post 3/9/12

Today in class we:

-Measured/watered Fast Plants
- Researched in IMC for Wildlands project

HW: 1. Read CH 28 by Monday
2. bring TEXTBOOK to class ALL next week!
3. wildland project
4. STUDY


Chapter 16 Overview:

*The required pages for Chapter 16 are pages 320-334 & 340-341

Why should we study plants?
Provide us with Oxygen, food, clothing, paper, supplies, energy, and sustain life.

Plant Kingdom is: -Multicellular
-Eukaryotic
-Autotrophic (by photosynthesis)

Land Adaptations: 

1. Mycorrhizae: root-fungus combinations-fungi absorb water and minerals from soil, plant sugar nourishes fungi

2. Stomata: Microscopic pores through leafs surface exchange CO2 and O2

3. Cuticle: Waxy layer coating leaves and other aerial parts to help retain water

4. Lignin: Chemical which hardens cell walls

5. Roots and Shoots

6. Xylem tissue: (transports water up) and Phloem tissue (transports food around)

7. Protected Embryo: gametangia -a jacket of protective cells surrounding a moist chamber where gametes can develop without drying out

8. Seed Dispersal: Rely on wind or animals

Origin of Plants from Green Algae

Charophyceans: group of multicellular green algae; closest to plants (in evolution)

Four Major Periods of Plant Evolution:

1. Bryophytes (mosses)

2. Ferns

3. Gymnosperms (conifers)

4. Angiosperms (flowering)

1. Bryophytes- Mosses (many plants growing in a tight pack)

Key Characteristics:

• No cuticle
• Need water to reproduce 
• Flagellated sperm
• No vascular tissue
• Like damp/shady places

Green Spongy plant = Gametophyte (male & female are separate plant shoots)(n)

Taller brown shoot with a capsule; grows out of gametophyte = Sporophyte (2n)

Alternation of Generations:

• 2 Generations that "take turns" producing each other
• Gametophytes produce eggs and sperm; unite to form zygote which then forms new sporophytes
• Sporophytes produce spores
• Spores develop new organism without uniting
• New organism produces gametophytes again
• Process repeats
• ***Gametophyte = Larger more obvious plant in mosses

2. Ferns

Key Characteristics: 

• most in tropics/temperate woodlands
• vascular tissue present (Xylem and Phloem)
• Sperm flagellated
• ***seedless (have spores)

Alternation of Generations:

• Sporophytes are diploid and gametophytes are haploid

• ***Sporophyte is the dominant stage in ferns (Gametophyte for mosses)
• Heart Shaped gametophyte = prothallus

3. Gymnosperms:

Key Characteristics: 

• Cone Bearing
• Life cycle on dry land
• oldest organisms on earth
• retain leaves throughout year
• thick cuticle
• source of wood and paper

Reproduction: 

• Pollen contains cells that develop into sperm
• Wind carries pollen to female cones
• Eggs develop in female cones
• ***Evolution of a seed- a plant embryo packaged along with a food supply without a protective coat
• Bear seeds naked on cone scales
• Seeds germinate under favorable conditions
• 2 types of cones
• Female cone is most familiar (hard, woody, scaly)
• Male cone is smaller; lower on the tree; release pollen

4. Angiosperms:

Key Characteristics:

• Dominate most regions
• 250,000 Species
• Vascular tissue
• ***Evolution of a flower = Responsible for unparalleled success
• Flowers display male + female parts
• insects/animals transfer pollen
• Flower: Short stem with modified leaves: sepals, petals, stamens, carpels

Parts Of A Flower + Function:

Sepals: green, enclose flower before it opens

Petals: Attract insects 

Stamen: Filament (stalk) bearing a sac called anther (male organ in which pollen develops)

Carpel: Sticky tip traps pollen (stigma), 

Ovary: Eggs develop here

Angiosperm Life Cycle:

• Pollen lands on stigma, tube goes down to ovule
• Deposits 2 sperm nuclei within female gametophyte = double fertilization
• One sperm cell fertilizes egg making zygote, developing into embryo
• Second sperm cell fertilizes another female gametophyte cell which develops into a nutrient-storing tissue called endosperm

Hope this helps summarize chapter 16 and the notes we did in class.

See you in class,

Mark

Next Scribe:
 Charlie