any hairlike outgrowth from the surface of a plant
Angiosperms
Flowering plants
Though they're relative newcomers to the plant world, 2/3 of today's plants are angiosperms
Cultivation
purposeful growing of plants to improve supply
Extensive Agriculture
Linked to Agronomy
Trying to get the most yield or profit with the least amount of input
Think wheat plant - you can't look at every last detail of every single wheat plant
Intensive Agriculture
Linked to horticulture
Large amount of input given the plant or area
Tends to have an increased cost
You're looking at every individual plant
Apple tree
Fruit, vegetable, flower production tend toward intensive
Extensive/Intensive crossover crops
Tobacco, Cotton, Rice
These involve more input than say corn or wheat, so they tend to be a little closer to intensive
Exceptions to places on Earth that support plant life?
The poles
Very, very, very dry deserts
Deep, deep oceans
High, high altitudes
What is the major factor affecting where plants live?
Climate
xeriphytes
adapted to live in dry, hot conditions
mesophytes
plant adapted for survival in moderate (not too wet, not too dry) habitats
hydrophyte
plant adapted for survival in very wet habitats
Where is the greatest amount of plant diversity found in the world?
Near the equator
Plants as food for humans
Of the 500,000-700,000 plant species, more than 80 percent of human food comes from six species
Tend to be grains - rice, wheat, corn, oats
What crops make up more than 80 percent of feed plants?
Corn, sorghum, barley, oats
What is the number one fiber crop?
Cotton
biormediation
use of plants to help remove contaminants such as heavy metals from the environment
Difference between spices and herbs
Spices tend to be seeds from more tropical areas
Herbs tend to be leaves from more temperate climates
Sink
Resources going into a plant
New leaves on a plant are a sink, because the plant is sending its energy to the development of leaves
Biopharmaceuticals
Medicinal drugs produced using biotechnology
Produced by means other than direct extraction from a plant or other living organism
Nutraceuticals
Foods (or chemicals present in foods) that have a medicinal effect on human health
Where do cacti store water?
Stems
Binomial system
Two names
How do we know what family a plant is classified as?
It's based on reproductive parts
Family Rosaceae
Rose family
-Apple, pear, quince, peach, strawberry, blackberry are all part of the Family Rosaceae
Family Solanaceae
Nightshade family
Potatoes, tomatoes, peppers, tobacco, petunia all fall into family solanaceae
Genus
A subcategory of family, categorization is based on similar flowers, roots, stems, buds and leaves
Genus prunus
Stone fruits
peaches, apricots, almonds, tart cherry, sweet cherry, plum
Species
A subcategory of genus
Composed of individuals that resemble one another
Able to breed among themselves, generally not able to breed with members of another species
Family Rosaceae, Genus Prunus, Species persica
Peach
Cultivar
Variety developed by plant breeders
Usually propogated vegetatively by stem cuttings or dividing
Clone
Originates from single plant specimen
Maintained in cultivation by vegetative propogation
All clones from parent plant are exactly alike
Latin descriptors for leaves
folius
folium
phyllum
Latin descriptor for creeping
reptans
Climbing
scandens
White
alba
albus
luco
Virens
Green
Red
rubro
Monocot
one seed leaf
corn
flower parts are in multiples of three
Dicot
2 seed leaf
4 or 5 flower parts
Morphology
shape or look
Examples of biennials
Hollyhocks
Thistle
2 growing seasons
Gymnosperm
Conifers
How do you group plants?
By use
Class (monocot v dicot)
Length of life cycle
Morphology
Flower, Fruit or Seed Structure (angiosperm, gymnosperm)
Types of stems
herbaceous (no woody tissue)
shrub (multiple stems)
tree (one main stem - trunk)
Stem growth forms
erect
decumbent
creeping
climbing
Adventitious roots
Roots in an unusual place, that originate from stem or leaf tissue rather than from another root
Fruit structure
Based on succulence (fleshy or dry) and anatomical features
What are the types of simple fleshy fruits
Drupes
Berry
Hesperidium
Pome
Pepos
Drupes
Hard stony seed center
Peach
Berry
Inner pulp with seeds
Tomato
Hesperidium
leathery rind, fragrant, partitions
orange
Pome
Overy or core surrounded by tissue
Apple
Pepos
Firm rind, fleshy, watery pulp, many seeds
Watermelon, pumpkin
Simple dry fruits
dehiscent
indehiscent
Dehiscent
break open at maturity to shed seed
beans, peas, milkweed
Indehiscent
do not break open at maturity
acorn, sunflower, corn, strawberry
achene
a small, dry, hard, indehiscent fruit, one-seeded, nut-like, often mistaken for a seed
strawberry, raspberry, sunflower
Aggregate Fruits
Derived from single flower with several or many pistils
Produce cluster of tiny fruitlets that remain on a single receptacle
Berries
Multiple fruits
derived from cluster of individual flowers that fuse together as the plant develops
Pineapple
Deciduous v. Evergreen
Decidiuous loses its leaves, evergreens stay green
How many gallons of water does it take to produce one serving of rice?
25
How many pounds of vegetables do humans consume per capita (in the U.S.)
417 pounds and we're still not eating enough veggies
Narrow channels that act as intercellular cytoplasmic bridges to facilitate communication and transport of materials between plant cells
Plasmodesmata
Purpose of a cell wall
protecting the intracellular contents
bestows rigidity to the plant
provides a porous medium for the circulation and distribution of water, minerals, and other nutrients
houses specialized molecules that regulate growth and protect the plant from disease.
Cell membrane
Semi-permeable
Composed of proteins or fats
Cytoplasm
Jelly-like substance within the cell
Nucleus
contains the genetic material that codes for protein so plants can build and repair
Chloroplast
Animal cells don't have this
Photosynthesis takes place here
Mitochondrion
Cell respiration
Converts carbs into energy
Vacuoles
Storage of water, certain chemicals
Also has a membrane
Helps keep cell rigid
Meristematic tissues
Tiny places where cells divide repeatedly
When cells take on a role, like becoming part of a stem,, they become differentiated
Apical meristem
At the tip of shoots and roots, for primary growth upward or downward
Lateral meristem
Help plants grow wider over time
Vascular tissues
"Pipes" that conduct food and water throughout the plant
xylem
conducts water and minerals
cells dividing inward
Phloem
conducts sugar, food produced via photosynthesis
cells dividing outward
Source
when you have a place producing something, such as leaves producing photosynthesis, that's a source
Sink
When you have something that needs attention, such as new leaves developing, that's a sink
Phloem makes it possible for the source to get food to the sink
Cambium
meristematic tissues giving rise to new xylem and phloem
Four types of roots
Tap (many times, food source)
Fibrous (hold topsoil in place, prevent soil erosion)
Prop (penetrate soil for anchorage)
Aerial (may penetrate soil, may attach to other plants or objects)
What types of stems have vascular cambium
dicots
monocots do not
Cambium
gives rise to new tissues laterally
Nodes
where leaves attach to stem
Internodes
space between nodes
Fruit which contains one hard and stony seed
Drupe
Stone fruit
Fruit which has a firm rind, fleshy watery pulp and numerous seeds
Pepo
pumpkin, watermelon
Fruit which has a leathery rind with aromatic oils
Hesperidium
oranges
simple fleshy fruit with inner pup and seeds
berry
tomato, banana
Pome
ovary or core surrounded by edible, fleshy tissue (apple)
For the plant named Mentha piperita 'Chocolate', which is the cultivar?
Chocolate
Monocots have characteristics including
B. Embryo has single cotyledon
A growing point that arises from a cell that did not contain preformed root or shoot initials is called
adventitious
Characteristics of plants
usually can produce its own food
reproduces
rareley is able to move around
many are green due to having chlorophyll
Invented the binomial nomenclature system of naming plants
Carl Linneaus
T/F Simple dry fruits that break open at maturity are known as indehiscent
False
Dehiscents break open
Which of the following statements is not true?
D. A perennial plant completes its life cycle in one growing season.
Where are guard cells found on a leaf?
On the epidermis
When a stem contains one leaf per node, what type of leaf arrangement is it?
Alternate
Opposite leaf arrangement
an arrangement of leaves (or buds) on a stem (or twig) in which the leaves emerge from the stem in opposing pairs
Alternate leaf arrangement
an arrangement of leaves (or buds) on a stem (or twig) in which the leaves emerge from the stem one at a time. This often makes the leaves appear to alternate on the stem.
Whorled leaf arrangement
A plant has whorled leaves when there are three or more equally spaced leaves at a node.
Channels or bridges that connect cells are called:
Plasmodesmata
Heart shaped leaves are said to be
Cordate
Leaves with five lobes
digitate
Leaf margins that look like a knife's edge are
Serrate
Leaves that sprout out in a circular patern from a center
Palmate
If a plant has rotundafolia in its name, its leaf shape is:
Round
Oval shaped leaf may be called
ovate
A dioecious plant may have what type of flowers?
D. All of the above. Dioecious means two houses
When a plant has perfect flowers it is
Synoecious
T/F In a stem, the phloem is always located toward the outside of the stem or root, and the xylem is always located toward the inside
True
Simple leaf
undivided blade
if they have divisions, they do not reach the midrib
Compound leaf
have a fragmented blade, with divisions reaching the midrib
have leaflets (walnut)
Four whorls of a flower, starting with the outermost
Sepals (typically green)
Petals
Stamens (male parts)
Pistils (female parts)
Collectively, sepals are called
Calyx
Collectively, petals are called
Corolla
Colored sepals are called
Tepals
Stamen parts
Anther (produces pollen)
Filament (stalk that supports anther)
Nectaries (at base of filament, produce sticky, sugary substance)
Adroecium (all the stamens)
Pistil parts
Stigma (receives pollen, usually sticky)
Style (connects stigma to ovary)
Ovary (contains the egg and one or more ovules)
Gynoecium (all the pistils)
What types of leaf attachments are there?
Petioles
Sessile
Sheathing (monocots, new shoots come through the others)
Leaf venation
Paralell veins (monocots)
Pinnate (main vein, called midrib, from which all other veins arise)
Palmate (major veins all arise from same place, somewhat like fingers coming from the palm of a hand)
Trifoliate (three leaflets, such as a shamrock)
Receptacle
enlarged part of pedicel where floral parts arise
on a strawberry, the receptacle is the fleshy part
in an apple, the ovary is recessed into the receptacle
pedicel
supports an idividual flower (connects the flower to the peduncle, or main stalk)
Petiole
leaf connection
One half of the world's cropland is in
China, India, Russia and the U.S.
The three major crops grown in the U.S.
Corn, wheat and soybeans
What are the top three crops in the world?
Wheat, corn, rice
Most important fiber crop in the world
Cotton
Primary starch product worldwide
White potatoes
Main sugar crop in US?
Sugar cane
The growing point of a plant's shoots or roots, with actively dividing cells is known as the
Apical meristem
Complete flower
Contains all four flower parts
Incomplete
missing one or more parts
Perfect
contains stamen and pistil (doesn't matter if it's lacking the sepals or petals)
Pistillate
only female parts
Stamenate
Only male
Give an example of an incomplete, but perfect flower
Corn - tassles are male, silks are female
monoecious plants
one house
pistillate and staminate on same plant, like corn or begonias
dioecious
two houses, only staminate or pistillate, like buffalo grass or holly
syonecious
contains perfect flowers
inflorescences
multiple flowers are on one peduncle (stem)
Rachis
central axis, peduncle
Solitary flower
Only one flower on top of the rachis
Spike
Sessile, flowers are attached directly to the rachis
Examples of sessile or spike flowers
Corn (cob is the rachis) Salvia
Racme
Just like spike only with pedicels
Panicle
A compound raceme (the raceme has pedicels coming off the rachis, and the panicle has pedicels coming of the pedicels that came off the raceme)
Corymb
Different lengths of pedicels, attaching at a different locations and creating a flat-topped inflorescense
Umbel
All pedicels attach at the base
head
many sessile flowers tightly clustered on a flattened receptical
Capitulum
similar to head, but globe shaped (clover)
Samara
maple seed wings
Parts of seed
embryo (tiny plant in seed - it's a living organism)
endosperm (food reserves - orchids do not produce this)
seed coat (protective outer surface)
After fertilization, what happens?
Ovary swells and becomes either fleshy or hard and dry to protect develping seeds
Parts of embryo
Radicle - emrbryonic root
Cotyledons - embryonic leaves
hypocotyl - below embryonic leaves
Epicotyl - above embryhonic leaves
Global seed market
$37 billion worldwide, wholesale value
Fasted growing category is vegetable seeds
Largest seed market is in the U.S.
Fruit
Contains and protects seeds
Contains mature ovary and one or more ovules
Surrounded by ovary wall
Pollination
occurs when pollen from the anther lands on the stigma
Ovules
turn into seeds
caryopsis
grass family, whole seed
fused to ovary wall
indehiscent dry fruit (corn, sorghum, wheat, oats, rye)
Primary roots
Develops from the Seed
Or from Base of a Stem in Case of Ferns
Secondary roots
usually found in grain crops
spongy mesophyll parenchyma
contains the intercellular spaces through which carbon dioxide, oxygen, and water pass.
The outside layer or skin of the leaf is largely made up of
epidermal cells, which contains openings or pores called stomates, each surrounded by two guard cells.
Generally more stomates in the lower epidermal layer.
Primary function of leaves
photosynthesis
Guard cells
control the opening and closing of the stomata through which carbon dioxide enters, and oxygen is released.
Water also enters or escapes through the stomata
Transpiration
Loss of water from the leaf by evaporation
helps regulate leaf temperature.
Also draws water into & through the xylem.
Leaf Modifications
Cotyledons
Spines
Tendrils
Storage Leaves
Bracts
Perianth
Corolla and Calyx
Spikelet
Individual flowering unit of grasses
Spikelet contains (8 parts)
Glumes
Rachilla
Florets
Lemma
Pales
Lodicules
Pistil
Stamens
Glumes
Leaflike bracts at base of spikelet and enclose the rest of spikelet
Rachilla
Central axis of the spikelet
Stalk-like structure that connects all the florets
Florets
1 or more per spikelet
contain stamens and pistil with other bracts
uppermost floret usually undeveloped and sterile
Lemma
The first bract at the base of the floret
Its tip is called the awn
Palea
A bract located just above and opposite the lemma
Together, the lemma and palea enclose the stamens and pistil
Lodicules
v. small bracts at base of pistil
serve no known funcion except for identification
Pistils
female organ of the plant
Stamens (grass)
Male reproductive organs of the plant
in monocots, the stamens occur in multiples of 3
most grasses have 3 stamens
Monocot seed part: Pericarp
Protection
it's the seed coat
Monocot seed part: endosperm
carbohydrates and other energy compounds for embryo during germination
monocots tend to have endosperm even at the point of germination
monocot seed parts: cotyledon
seed leaf (scutellum)
Monocot seed parts: Coleoptile
Protective sheath for leaves during emergence
Monocot seed parts: plumule
embryonic foliar leaves
becomes shoot
Monocot seed parts: radicle
develops into the primary root
monocot seed parts: coleorhiza
protective sheath around the radicle
dicot seed parts: hilum
scar where seed attached to ovary wall
dicot seed parts: micropyle
minute scar where pollen tube entered the ovule before fertilization of egg
dicot seed part: raphe
slight ridge along edge of seed
dicot seed part: testa
dicot seed coat
dicot seed parts: cotyledons
food reserves for seed dormancy and germination
dicot seed parts: plumule
contains embryonic foliar leaves and epicotyl
epicotyl is above cotyledons, attaches to plumule
dicot seed parts: hypocotyl
elongates to pull the cotyledons and plumule out of the ground in epigeal emergence
dicot seed parts: radicle
develops into primary root at germination
becomes tap root
dicot seed parts: cotyledonary node
where two cotyledons attach to rest of embryo
Germination Stage I
Activation/imbibation
rapid absorption of water
Germination Stage 2
Lag Phase/Digestion & Translocation
metabolic processes kick in
Germination Stage III
Cell division & elongation
radicle emerges first
then plumule emerges
Epigeal germination
cotyledons emerge above soil surface
results from hypocotyl extension
Hypogeal germination
seed cotyledons remain underground
results from epicotyl elongation
epigeal advantages
cotyledons may protect apical meristem if unfavorable weather conditions occur
herbivores may damage the cotyledons and not destroy the entire plant