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Chapter 35
List the characteristics of an angiosperm.
Dominant Generation: Sporophyte
Sperm Transport: Wind or animal dispersal
Fluid Transport: Vascular
Dispersal Unit: Seeds
Explain the differences between monocots and dicots.
DICOTS
MONOCOTS
Cotyledons: 2
Cotyledons: 1
Leaf Venation: netted
Leaf Venation: Parallel
Flower Parts: 4’s or 5’s
Flower Parts: 3’s
Vascular Bundles: organized in a circle
Vascular Bundles: scattered
Root: taproot (single, large)
Root: cluster of fine roots (fibrous
system
To see a diagram click here: Figure 3503
Describe the importance of root systems and shoot systems to plants and explain
how they work together.
Root System: (beneath ground) anchor plants, absorb and conduct water and
nutrients, and stores food. Shoot System: (above ground) stems, leaves, and flowers.
Describe how plant cells grow.
Plant cells have apical growth (vertical growth) that is primary growth and/or lateral
growth (horizontal growth), which is secondary growth.
Distinguish between parenchyma and collenchyma cells with regards to structure and
function.
Parenhcyma cells have the ability to divide, and perform most of the plants metabolic
funsctions of synthesis and storage. Collenchyma cells support young growing parts
of the plant with their unevenly thickened cell walls.
Describe the differences in structure and function of the two types of sclerenchyma
cells.
Fibers: long, slender, tapered cells occurring in bundles. Sclerids: shorter, irregularly
shaped cells.
Explain the differences between simple tissues and complex tissues.
Xylem: carries water and nutrients. Phloem: carries sugar.
Describe the functions of the dermal tissue system, vascular tissue system and
ground tissue system.
Dermal tissue system: covers the outside of plant parts (outer layer). Vascular tissue
system: consists of xylem and phloem. Ground tissue system: consists of the 3 types
of cells (parenchyma, collenchyma, and sclerenchyma).
Distinguish between the arrangement of vascular tissues in roots and shoots.
Using a diagram, describe the basic structure of a root, a stem, and a leaf.
Picture of stem, leaves and roots: Figure 3504
Diagram of different type of leaves: Figure 3507
Chapter 36
List three levels in which transport in plants occurs and describe the role of
aquaporins.
Uptake and release of water and solutes by individual cells
Short-distance cell-to-cell transport at the level of tissues and organs
Long-distance transport of sap in xylem and phloem at the whole-plant level
Aquaporins do not actively transport water, but rather facilitate its diffusion
(osmosis).
Trace the path of water and minerals from outside the root to the shoot system.
Define water potential.
Water potential: The free energy of water that is a consequence of solute concentration and
applied pressure; physical property predicting the direction water will flow
Explain how solute concentration and pressure affects water potential.
Addition of solutes to water lowers the water potential into the negative range.
Increased pressure raises the water potential into the positive range.
A negative pressure, or tension, may also move water across a membrane; this bulk flow
(movement of water due to pressure differences) is usually faster than the movement
caused by different solute concentrations.
Predict the direction of net water movement based upon differences in water
potential between a plant cell and a hypoosmotic environment, a hyperosmotic
environment or an isosmotic environment.
According to the transpiration-cohesion-adhesion theory, describe how xylem sap can
be pulled upward in xylem vessels.
Transpiration reduces pressure in the leaf xylem; this creates a tension which pulls sap up
through the xylem from the roots.
Explain why a water potential gradient is required for the passive flow of water
through a plant, from soil.
Describe both the disadvantages and benefits of transpiration.
List three cues that contribute to stomatal opening at dawn.
Light. Induces guard cells to take up K+
Decrease of CO2 in leaf air spaces due to photosynthesis in the mesophyll
An internal clock in the guard cells; this will make them open even if plant is kept in dark (a
circadian rhythm approximates a 24-hour cycle)
Describe environmental stresses that can cause stomata to close during the daytime.
Guard cells may close stomata during the daytime if:
There is a water deficiency resulting in flaccid guard cells.
Mesophyll production of abscisic acid (a hormone) in response to water deficiency signals
guard cells to close.
High temperature increases CO2 in leaf air spaces due to increased respiration, closing
guard cells.
Chapter 37
Describe the chemical composition of plants including:
Percent of wet weight as water: 80-85%
Percent of dry weight as organic substances: 95%
Percent of dry weight as inorganic minerals: 5%
Distinguish between macronutrient and micronutrient.
Macronutrients are elements required by plants in large amounts. Micronutrients are
elements required by plants in small amounts.
List the nine macronutrients required by plants and describe their importance in
normal plant structure and metabolism.
Carbon: component of plant’s compounds. Oxygen: component of plant’s compounds.
Hydrogen: component of plant’s compounds. Nitrogen: component of nucleic acids,
proteins, hormones, & coenzymes. Sulfur: component of protein, coenzymes.
Phosphorus: component of nucleic acids, phospholipids, ATP, several coenzymes.
Potassium: cofactor functional in protein synthesis; major solute functioning in water
balance; operation of stomata. Calcium: important for formation and stability of cell
walls; maintenance of membrane structure and permeability; activates some
enzymes; regulates many responses of cells to stimuli. Magnesium: component of
chlorophyll; activates many enzymes.
List seven micronutrients required by plants and explain why plants need only minute
quantities of these elements.
Chlorine: required for water-splitting step of photosynthesis; functions in water
balance. Iron: component of cytochromes; activates some enzymes. Boron: cofactor
in chlorophyll synthesis; may be involved in carbohydrate transport and nucei acid
synthesis. Manganese: active in formation of amino acids; activates some enzymes.
Zinc: active in formation of chlorophyll; activates some enzymes. Copper: component
of many redox and lignin-biosynthetic enzymes. Molybdenum: essential for nitrogen
fixation; cofactor functional in nitrate reduction. Nickel: cofactor for an enzyme
functioning in nitrogen metabolism.
Explain how soil is formed.
The weathering of solid rock produces soil. Living organisms may accelerate the
process once they become established. The eventual result is topsoil, a mixture of
decomposed rock of varying texture, living organisms, and humus.
Explain how humus contributes to the texture and composition of soil.
Some living organisms inhabit the soil and are involved in producing humus, which is
decomposing organic matter that improves the texture and mineral content of soil.
Explain why plants cannot extract all of the water in soil.
Some water is bound so tightly to hydrophilic soil that plants cannot extract it.
List the three mineral elements that are most commonly deficient in farm soils.
Describe the environmental consequence of overusing commercial fertilizers.
Chapter 38
Outline the angiosperm life cycle.
Within the ovary of a flower, the egg of an ovule is fertilized by a sperm cell released
from a pollen tube. After fertilization, the ovule matures into a seed containing the
embryo, and the ovary develops into a fruit.
List the four floral parts in their order from outside to inside of the flower.
Sepals, petals, stamens, and carpels
From a diagram of an idealized flower, correctly label the following structures and
describe their function:
Sepals: enclose and protect a floral bud before it opens. Stamen: consists of a stalk
(filaments) & the anther, where pollen grains (male develop.) Petals: advertise the
flower to insects and other pollinators. Carpel: has a style, which leads to an ovary
located at the base of the carpel. Developing within the ovary are one or more ovules,
where egg-containing embryo sacs (female) develop. At the tip of the carpel is a
stigma, which serves as a landing platform for pollen brought form other flowers by
wind or animals. Diagram: Figure 3802
Explain by which generation, structure, and process spores are produced.
Explain by which generation, structures, and process gametes are produced.
Describe the formation of a pollen grain in angiosperms.
Distinguish between pollination and fertilization.
Pollination is the placement of pollen onto the stigma of a carpel and fertilization is
the union of haploid gametes to produce a diploid zygote.
Describe how pollen can be transferred between flowers.
Some plants use wind as a pollinating agent; others interact with animals that
transfer pollen directly between flowers.
From a diagram, identify the following structures of a seed and recall a function for
each:
Seed coat: enclose embryo and food supply. Radicle: where the hypocotyl terminates.
Endosperm: where cotyledons absorb their nutrients. Epicotyl: top portion of the
embryo, becomes the shoot tip. Cotyledons: transfer nutrients from endosperm to
embryo. Hypocotyl: below epicotyl and attached to cotyledons, becomes young shoot.
Plumule: attached to epicotyl, are young leaves. Diagram: Figure 3809
Explain how a monocot and dicot seed differ.
Dicots there are 2 fleshy cotyledons. In monocots most of the storage tissue is
endosperm, with 1 cotyledon.
Describe several functions of fruit and explain how fruits form.
A fruit develops from the ovary of the flower while seeds are developing from the
ovules. A fruit protects the seeds and aids in their dispersal by wind or animals. A
true fruit is a ripened ovary.
Chapter 39
List five classes of plant hormones, describe their major functions, and recall where
they are produced in the plant.
Auxin: produced in the apical meristem, promote plant growth by facilitating the elongation of
developing cells.
Gibberellins: promotes cell growth, they are synthesized in young leaves, roots, and seeds.
They are also involved in the promotion of fruit development and of seed germination, and
the inhibition of again in leaves.
Cytokinins: a hormone that stimulates cytokinesis (cell division). Are produced in roots (and
perhaps elsewhere). The also influence the direction of organ development, stimulates the
growth of lateral buds, and have been found to delay senescence (aging) of leaves.
Ethylene: a gas that promotes the ripening of fruit and inhibits the elongation of roots, stems,
and leaves, and influences leaf abscission, the aging and dropping of leaves.
Abscisic Acid: is a growth inhibitor. In many species of plants ABA maintains dormancy in
seeds. In buds, it delays growth and causes the formation of scales in preparation for over
wintering.
Explain how a hormone may cause its effect on plant growth and development.
They are small molecules, capable of passing through cell walls that affect the division,
growth (elongation), or differentiation of the cells. The specific effect of a hormone depends
upon the particular hormone, its concentration, the target cell, and the presence or absence
of other hormones.
Define circadian rhythm and explain what happens when an organism is artificially
maintained in a constant environment.
Circadian rhythm is a clock that measures the length of daylight and night.
Define photoperiodism.
Photoperiodism is the response of plants to change in the photoperiod, or the relative length
of daylight and night.
Distinguish among short-day plants, long-day plants, and day-neutral plants; give
common examples of each; and explain how they depend upon critical night length.
Long day plants flower in the spring and early summer when daylight is increasing.
Short day plants flower in late summer and early fall when daylight is decreasing. These
plants flower when daylight is less than a critical length (or when night exceeds a critical
length). Day neutral plants do not flower in response to daylight changes. Some other cue,
such as temperature or water, triggers flowering.