Chapter 3: Principles of Plant Growth

Plant cell

Cell Wall

Cell Wall

A rigid outer layer of the cell composed primarily of cellulose and lignin. The cell wall is durable enough to give plants structure and support, yet porus enough to allow water and other materials to pass in and out of the cell

Cytoplasm

The fluid surrounded by plasma membraneMade up of a complex protein matrix or gel

Endoplasmic Reticulum (ER)

Endoplasmic Reticulum (ER)A complex structure consisting of folded sacs & tunnels. Proteins produced by the ribosomes are passed through the ER membrane into the ER lumen, where they are sealed in vesicles for transport to the cell membrane, golgi apparatus, or other cell organelles. ER covered with ribosomes if referred to as “rough ER”. Whereas ER with few or no attached ribosomes is termed “smooth ER”

RibosomesThe site of protein synthesis. When found floating freely in the cytoplasm, they produce protein that will be used in the cell. When attached to the ER, they produce proteins used outside the cell.

Chlorophyll

Chlorophyll

The site of photosynthesis. Chloroplasts synthesize the pigment chlorophyll, giving plants their green color. Chlorophyll, along with other pigments, allow plants to capture and store energy from sunlight, which can later be utilized for photosynthesis.

Mitochondria

Mitochondria

The site of respiration within the cell. Mitochondria utilize oxygen to produce adenosine triphosphate (ATP). In turn, ATP provides energy for almost all the cell’s chemical reactions. Mitochondria contain DNA and are capable of manufacturing their own proteins.

Nucleus

Nucleus

The control center of the cell. The nucleus contains chromosomal DNA that regulates the production and structure of proteins within the cell. The nucleus is surrounded by the nuclear membrane, a porous membrane that allows materials to pass in and out of the nucleus.

Golgi Complex

Golgi Complex

A series of flattened sacs and vesicles. Proteins, as well as other molecules such as hormones & carbohydrates, pass through the various sacs of the golgi complex where they are chemically modified. After modification, the molecules are placed in vesicles for transport within ad out of the cell

Vacuoles

A fluid filled cavity that stores water, salts, enzymes, food, and other materials required by the cell. They can make up 90% of the cell. The help support the cell.

Plant TissuesGroups of cells that function as a unit. 4 groups.

Meristematic- a region in which undifferentiated cells divide.

Fundamental- parenchyma tissue in monocots. (equivalent of cortex and pith in dicots). Storage units.

Protective- Epidermal “skin” protects.

Vascular- Xylem & Phloem is the transport system.

Plant Organs

Groups of tissues form organs.

RootsStemsLeaves

Root

Stem

Terminal budAxillary budNodeInternodeLenticelTerminal bud scarBundle scarLeaf scar

Leaves

Photosynthesis

6 CO2 + 12 H20 Green Plant C6H12O6 + 6 H20 + 6 O2

Light Energy

Transpiration

Loss of water by the plant.

How does the plant protect itself from losing to much water?

Heredity

Plant breeding.

Growth –vs- Time

S – shape growing curve.Why is important to know when the plant is going to start a flush of growth?

Temperature

minimum, maximum, optimal temperatures for a crop

wheat min=40 max=90 (when flowering)

crops generally don't grow in areas where average 24 hour temperature <50 or >130

Radiant Energy (Amount, quality & duration of sunlight)

amount of light energy receivedmeasured in foot candles

summer day = 10,000living room = 20

crops need 100-10,000if not enough light, grow tall (leggy, weak stems)weed control reduces competition for lightplanting rate & row spacingsome plants need shade (tobacco), burlap, lathes, screens

Radiant Energy (Amount, quality & duration of sunlight)

energy that travels in wavelengthsshort wavelengths = high energy (blue)long wavelengths = low energy (red)ultraviolet = invisible

Radiant Energy (Amount, quality & duration of sunlight)

amount of light of different colorsplants absorb red & blue, reflect

greensmoke filters blue, sun looks redglass & plastic filter light

Water

Photsynthesis

Needed for metabolic functions

Transpiration

Evaporation

Evapotranspiration

Atmosphere

The Primary gases are oxygen and Carbon dioxide for respiration and photosynthesis.

Excess sulfur dioxide, ethylene, fluorides & others can harm plants

Nutrient Requirement

C HOPKNS CaFe Mg Na Cl Cu Mn Co Zn Mo BC Hopkins Café; mighty good (but) Not always Clean. CuM’n CoZ’n MoBy?

Nickel

Photoperiodism

Some plants needs a certain number of hours of day length to flowerShort day plants (i.e. poinsettias, strawberries, mums) need long nights uninterrupted to flower

Long Day plants (i.e. spinach sugar beets) need short nights

Day neutral (i.e. tomatoes)