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Finals Study Guide Semester 2
Honors Biology
Unit 9- Plants
Objectives Ch. 16
1. Describe 8 terrestrial adaptations of plants
1.Mycorrhizae-root-fungus combinations - fungi absorb water and minerals
from soil, plant sugar nourishes fungi
2.Stomata - microscopic pores through leaf’s surface, exchange CO2 and O2
3. Cuticle - waxy layer coating leaves and other aerial parts, helps retain water.
4. Lignin - chemical which hardens cell walls (skeleton)
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 w/o drying out (in female parent)
8. Seed dispersal - rely on wind or animals
2. Explain how plants evolved from green algae
Charophyceans are a group of multicellular green algae closest to plants in
evolution.
Next came 4 major periods of plant evolution: bryophytes (mosses); ferns;
gymnosperms (conifers); and angiosperms (flowering).
3. Characterize the highlights of plant evolution by describing the following plant
types, how they have adapted to land, and their basic characteristics:
A. Bryophytes (mosses)
Bryophytes - mosses = many plants growing in a tight pack.
• No waxy cuticle and do not retain developing embryos w/i mother plant’s
gametangium.
• Need water to reproduce; sperm are flagellated, must swim through water to
reach eggs
• No vascular tissue to carry water(grow low to ground) and lack lignin
• Like damp, shady places
• Green spongy plant = gametophyte (male & female are separate plant
shoots)(n)
• Taller brown shoot with a capsule, grows out of gametohyte = sporophyte
(2n)
• Archegonium (female gametophyte)
• (Antheridium = male gametopyte.)
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B. Ferns
Ferns - diverse with 12,000 species, most in tropics, many in temperate
woodlands of U.S.
Evolution of vascular tissue (xylem and phloem)
Sperm are still flagellated-must swim through a film of water to fertilize eggs
Are still seedless - have spores
During Carboniferous Period, ferns in swamp forests converted to coal (black sedimentary rock made up of fossilized plant material)
A. Gymnosperms
Gymnosperms-cone-bearing seed plants (conifers)
Complete life cycle on dry land
Withstand long, harsh winters
Ex: Pines, firs, spruces, junipers, cedars, redwoods
Tallest, largest, oldest organisms on Earth
Nearly all are evergreens-retain leaves throughout year
Needle-shaped leaves-survive dry seasons.
Thick cuticle and stomata in pits reduce water loss
They are our wood & paper source. Wood= vascular tissue with lignin
Greater development of the sporophyte generation-gametophytes live in
cones.
B. Angiosperms
Angiosperms - flowering plants, dominate most regions
250,000 species vs. 700 conifer species
Supply nearly all our food and fiber for textiles, some lumber
Refined vascular tissue - water transport more efficient
Evolution of flower = responsible for unparalleled success
Flowers - display male and female parts
Insects and animals transfer pollen from male part of one flower, to female part
of another flower. Advantage? (vs. wind)________
Flower = short stem w. modified leaves: sepals, petals, stamens, carpels.
9. Describe how plants are being cut down, and how they can be a non-renewable
dsresource:
A. Coniferous forest
B. Rainforest
they give us food, clothing, energy supplies, lumber, paper, oxygen, water,
recreation, art, and products such as rubber.
And clear-cutting practices have become common, often exceeding the rate of
reforestation.
Objectives Ch. 28
10. Describe and explore in the laboratory, the structure and function of a flowering
plant. Include descriptions of the following:
A. Monocots and Dicots
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Monocots include orchids, palms, lilies, grains, grasses.
Dicots include shrubs, trees (except for conifers), ornamental plants, many
food crops.
B. Plant organs: roots, stems, leaves
1. 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.)
2. 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.
3 kinds of Modified 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.
3. 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.
C. Types of plant cells:
1. parenchyma
Parenchyma cells - most abundant cell, for food storage,
photosynthesis. Only primary cell walls.
2. collenchyma
Collenchyma cells - provide support in growing parts of plant. Only
primary cell walls.
3. sclerenchyma
Sclerenchyma cells - have thick secondary walls with lignin (wood).
When mature, most are dead - rigid cells support plants. Make rope
and clothing.
4. water-conducting
5. food-conducting
D. Plant tissues:
1. dermal tissue (epidermis, stomata)
Dermal-covers, protects, waxy coating
Stomata - in epidermis of leaf and some stems, are tiny pores between
guard cells - minimizes water loss, allow gas exchange
2. vascular tissue (xylem, phloem)
Xylem - contains water conducting cells - move water & minerals up
stem
Phloem -contains food conducting cells -transport sugars from leaves
or storage tissue to other parts of plant
3. ground tissue (mesophyll)
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 cortex-determines which
substances pass between cortex and vascular tissue.
Pith - fills center of stem in dicots, food storage.
Mesophyll - ground tissue of a leaf, for gas exchange and
photoshythesis
11. Depict the life cycle of a flowering plant.
A. The flower, parts of
Upper epidermis, Lower epidermis, Mesophyll, Cuticle, Vein, Xylem,
Phloem, Guard cells, Stomata, Palisade Layer, Spongy layer
B. Pollination
C. Fertilization (double)
Double fertilization occurs:
– one sperm fertilizes egg forming diploid zygote which becomes the
embryo;
– other sperm joins to form the triploid central cell, which develops into
endosperm, nourishing the embryo
D. Seed formation
Seed Formation:
Embryo develops cotyledons.
These organs absorb nutrients from endosperm.
Embryo develops into mature seed with tough protective seed coat
enclosing endosperm.
Seed becomes dormant until seed germinates.
Dormancy allows time for seed dispersal, favors survival for good
environmental contitions
E. Fruit formation
Fruit formation:
Fruit = mature ovary
Houses and protects seeds, disperses them from parent
F. Seed germation
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Seed Germination:
Seed takes up water and expands, ruptures its seed coat
Embryo resumes growth (from dormancy)
Embryotic root emerges, then shoot; a hook forms near its tip (protection)
True leaves expand from shoot tip, and photosynthesize
In pea, cotyledons remain behind in soil and decompose (see above)
In beans, cotyledons emerge from soil and become seed leaves, which
photosynthesize
Only small fraction of seedlings live to reproduce
12. Describe how plants grow:
A. annuals, biennials, perennials
Annuals - mature, reproduce and die in 1 year or growing season. Ex: wheat,
corn, rice, impatients
Biennials - live for 2 years; flower and seed occur during second year. Ex:
carrots
Perennials - live and reproduce for many years. Ex: trees, shrubs, some grasses.
B. Primary growth- lengthening (meristems)
Primary Growth = lengthening
Meristem - cells that divide and generate new cells and tissues
C. Secondary growth – thickening
1. vascular cambium in cylindrical meristem (secondary xylem/wood)
Wood - dead xylem tissue
Vascular cambium - gives rise to secondary phloem and secondary
xylem. Secondary xylem is produced each year = thickness of
perennial and/or wood. This results in annual growth of rings. Each
tree ring has cylinder of spring wood (larger cells) and of summer
wood.
2. bark (secondary phloem)
Everything external to the vascular cambium ( secondary phloem,
cork cambium, cork) = bark
3. cork cambium, cork cells
Cork cambium - produces cork (dead when mature, protects stem)
4. outer bark
Objectives Ch. 29
13. Define sap, and explain what it does in plants
Sap -watery solutions moving through vascular system.
In xylem it carries water and nutrients from roots to leaves and stems.
In phloem it transports sugar already made, from leaves to other parts of plants.
14. Describe how plants acquire and transport nutrients
A. Macronutrients
Macronutrients-need in large amounts: carbon, oxygen, hydrogen, nitrogen,
sulfur, phosphorus, calcium, potassium, and magnesium
B. Micronutrients
Micronutrients - need in extremely small amounts: iron, chlorine, copper,
manganese, zinc, molybdenum, boron, nickel. Mainly components of enzymes.
C. nutrient deficiencies
Deficiencies - quality of soil affects our own nutrition - Corn on left grown in
nitrogen rich soil; on right in nitrogen poor soil
D. soil to roots
Plants get CO2 from air (through stomata), minerals and H2O from
soil,(through root hairs) and O2 from soil.(through stomata).
A plant releases more O2 from photosynthesis than it consumes by respiration
Plant nutrition: all minerals that enter a plant root are dissolved in water
Go through epidermis & cortex of root; plasma membrane of root cells
(selectively permeable); to xylem
E. role of bacteria in nitrogen nutrition
Bacteria help with nitrogen nutrition: 3 types of soil bacteria:
1. Nitrogen-fixing bacteria - converts N2 in air to ammonium
2. Ammonifying bacteria - adds ammonium by decomposing organic
matter
3. Nitrifying bacteria - converts soil ammonium to nitrate - plants
take this up
Plants then convert nitrate back to ammonium to make proteins/organics.
F. transport of water
1. transpiration
Transpiration - greatest on sunny, warm, dry and windy days
Leaf stomata can help plants adjust transpiration rates-controls opening by
changing shape
Open during day and close at night, saving water. May close during day if plant
is losing water too fast.
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xylem
cohesion/adhesion
root hairs
stomata/ guard cells
G. transport of sugars
1. phloem
Phloem sap moves in various directions in plant
Phloem moves sugar from a source (leaf) to a sink (root or fruit)
2. direction of transport
Pressure-flow mechanism - the building of water pressure at source
end of phloem tube, and the reduction of water pressure at the sink
end causes water to flow from source to sink, carrying sugar with it.
15. Understand the role that each of the following plant hormones has on a plant:
A. Auxin
Auxin-produced by apical meristem, stimulates growth of shoot-causes cells to
elongate.
Requires certain concentrations: too much = inhibits stem elongation.
Usually, it inhibits roots (except in high concentrations it can elongate roots.)
B. Ethylene
Ethylene - a gas which triggers aging responses - fruit ripening, dropping
of leaves.
C. Cytokinins
Cytokinins - growth regulators, promote cell division. In roots, embryos, fruits.
Stimulate growth of axillary buds (branches and bushy.)
D. Gibberellins
Gibberellins - stimulates cell elongation and cell division in stems. Can
influence fruit development. Used in grapes-larger and more farther
apart in the cluster.
E. Abscisic Acid (ABA)
Abscisic Acid - slows growth. Ex: seed dormancy, esp. during adverse conditions
During drought, causes stomata to close during wilting, preventing further water
loss
11. Through research, an essay, and a PowerPoint presentation, explain the value of a
coniferous forest and a rainforest, and the role forests have in reducing global warming.
Honors Biology
Unit 10- Cellular Energetics
Topics: Atoms and Matter
1. Distinguish b/w elements, compounds, atoms, molecules, isotopes and ions
Element – cannot be broken down into other substances
 92 natural elements
 EX – oxygen, carbon, copper
 Each element has a symbol from its name
 Essential to life… (96%)
 Trace elements… (4%)
Compound – a substance containing 2 or more elements in a fixed ratio
 More common than elements
Atom –
 Indivisible – Greek
 Smallest unit of matter that retains the properties of an element
Isotopes – elements with the same number of protons and electrons, but a
different number of neutrons
 Radioactive Isotopes – the nucleus will decay, giving off particles and energy
Molecule – formed by atoms held together by covalent bonds
Ions are formed by either gaining or losing an electron.
 Atoms like to have full energy shells and will easily gain or lose 1-3 electrons
to do it.
2. Compare and contrast physical and chemical properties of matter
Matter – anything that occupies space and has mass
 Composed of chemical elements
3. Explain the importance of the structure of an atom, atomic number, mass number,
atomic weight and valence in chemistry
Atomic Structure –
 *Nucleus – central core of the atom, contains protons and neutrons
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*Proton – positively charged
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*Neutron – no charge
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*Orbitals - outside the nucleus
*Electron – negatively charged
Attraction between protons and electrons keep the electrons nearby the
nucleus.
Atomic number – same as the number of protons
If the atom is electrically neutral (number of protons = number of
electrons) then the atomic number also is the same as the number of
electrons.
Mass number – sum of the numbers of protons and neutrons in a nucleus
4. Identify types of chemical bonds and their functions
 Chemical bonds – formed by atoms trying to fill the outer most electron
shell
 Ionic bonds – attraction between oppositely charged ions (electron is
transferred)
 Example – Na has 1é in its outer shell and Cl has 7é in its outer shell. Na
can lose 1é to become Na+1 and and Cl can gain 1é to become Cl-1 and
both will have a full outer shell.
5. Differentiate b/w reactants and products in chemical reactions
Chemical Reaction – changes in the chemical composition of matter
 For a balanced chemical reaction the number of each element must be
equal on both sides of the reaction. Reactions cannot create or destroy
matter, it can just rearrange it.
 Reactants are usually the way the arrow is pointing away from
 Products are usually the way the arrow is pointing towards
 Ex: 6CO2 + 6H2O jgfkjljdkgjlkdfjgC6H12O6 + 6O2
 REACTANTS
PRODUCTS
Topics: Energy and Cellular Respiration
1. Define the term energy and contrast potential and kinetic energy
ENERGY – capacity to do work
 Kinetic Energy – energy of motion
 Potential Energy – energy because of its location or arrangement
 Conservation of Energy – energy can neither be created nor destroyed
 ENTROPY – measure of disorder or randomness
 Chemical Energy – energy stored in the chemical bonds of molecules; a form
of potential energy
2. State the first and second laws of thermodynamics and relate them to the nature of
energy transformations in living systems
 The First Law of Thermodynamics (Conservation) states that energy is always
conserved, it cannot be created or destroyed. In essence, energy can be converted
from one form into another.
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The Second Law of Thermodynamics states that "in all energy exchanges, if no
energy enters or leaves the system, the potential energy of the state will always be
less than that of the initial state." This is also commonly referred to as entropy.
3. Distinguish b/w endergonic and exergonic reactions
 Energy releasing processes, ones that "generate" energy, are termed exergonic
reactions.
 Reactions that require energy to initiate the reaction are known as endergonic
reactions.
4. Illustrate the chemical structure of ATP and summarize its role in cellular
metabolism
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ATP = adenosine triphosphate
ATP powers cellular work directly
ADP = adenosine diphosphate
ATP contains stored energy and will release energy when it breaks the bond to a
phosphate group to become ADP.
Break bonds = release energy
Create bonds = store energy
5. Define metabolism and relate to cellular respiration
Metabolism
 All chemical processes that occur in cells
 EX – cellular respiration
 Series of reactions
Respiration – harvests energy stored in sugars and organic molecules
A. Mitochondria
B. Consumers
CO2 + H2O
C6H12O6 + O2
6. Recognize the basic mechanisms of energy release and storage and the role of
chemical bonding
 As electrons “fall” from glucose to oxygen, the potential energy is unlocked.
 This rapid electron “fall” releases energy in the form of heat and light.
 Cellular respiration can harness this energy into small amounts for cells to use
productively.
7. Determine the role of hydrogen carriers and differentiate b/w oxidation and
reduction reactions
 Electrons bonded in the sugar molecule are transferred to oxygen by OxidationReduction Reactions (RedOx Reactions).
 Oxidation = lose of electrons
 Reduction = gain of electrons
8. Recognize the reactants, the products, the cellular location and the net production
of ATP for the following phases of respiration:
Glycolisis
 Glycolysis = splitting of sugar
 Splits glucose into two molecules of pyruvic acid
 Occurs in the cytoplasm of the cell.
 Generates a small amount of ATP directly. (2 ATP)
 Electrons are donated to the electron carrier NAD+.
 Does not require oxygen (Aerobic or Anaerobic process)
 Glycolysis generates ATP when enzymes transfer phosphate groups directly from
fuel molecules to ADP.
Krebs Cycle
 Pyruvic acid must be converted to Acetyl-CoA that can be used by the Krebs
cycle.
 When the bonds of pyruvic acid are broken the electrons are stored in NADH.
Later this is used to make ATP.
 Acetyl-CoA enters the Krebs cycle from Glycolysis.
 Completes the breakdown of sugar all the way to CO2.
 Occurs within the mitochondria.
 Generates a small amount of ATP directly.
 Captures more energy in the form of NADH and FADH2 that will be converted to
ATP in the electron transport chain.
Electron Transport Chain
 Electrons captured from food by NADH “fall” down the electron transport chain
to oxygen.
 Occurs within the inner membranes of the mitochondria.
 Uses the energy released by the “fall” of electrons to pump H+ ions across the
inner mitochondrial membrane.
 This creates a concentration gradient. The H+ ions tend to move back from high
concentration to low concentration and therefore fuel the ATP synthase to create
ATP from ADP.
 Generates a most of the ATP for the cell both directly and from electron carriers
like NADH and FADH2.
9. Explain how alcoholic fermentation and lactic acid fermentation can be used to
generate ATP in the absence of oxygen
Lactic Acid
 Not enough or no oxygen present.
 Occurs in muscle cells.
 Glycolysis supplies the ATP.
 Not efficient compared to cellular respiration.
 Lactic acid is a waste product. Soreness and burning after exercise is due to lactic
acid in the muscle tissue. Lactic acid is eventually converted back into pyruvic
acid in the liver.
Alcoholic Fermentation
 Fermentation is an anaerobic process (does not require oxygen).
 Yeast is fermented to produce the waste products ethyl alcohol and CO2.
 CO2 is what makes beer and champagne bubbly and bread dough to rise.
Topics: Photosynthesis
1. Distinguish b/w autotrophic and heterotrophic nutrition
Photosynthesis converts energy of sunlight into the chemical energy of sugar and
organic compounds.
 Almost all plants, some protists and some bacteria
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Autotrophs…
An organism that makes all its own organic matter from inorganic nutrients
Self feeders
Require inorganic compounds - CO2, H2O and minerals
Make organic compounds – carbohydrates, lipids, proteins, nucleic acids
producers
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Heterotrophs…
Cannot make organic molecules from inorganic ones
Other feeders
We must eat!
Depend on autotrophs for their organic fuel and material for growth and repair
consumers
2. Describe the structure of chloroplasts, their locations within plant cells, and
explain how chloroplast structure relates to its function
 Chloroplasts – organelle responsible for photosynthesis
 Leaves are the major site of photosynthesis (all green parts of a plant have
chlorophyll and chloroplasts and can undergo photosynthesis)
3. Describe wave-like particle behaviors of light and list the wavelengths of light
that are most effective for photosynthesis
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Sunlight is radiation or electromagnetic energy.
We are able to see only light that is reflected from an object.
EX – green leaves absorb red-orange and blue-violet light; therefore, reflecting
green light. Chloroplasts convert the absorbed energy.
4. Explain what happens when chlorophyll or accessory pigments absorb photons
 Photon – fixed quantity of light energy
 Pigment molecules absorb photons of light that “excite” the electrons to a higher
energy state
 As the electron “falls” back to the normal state is releases energy as heat or light
energy
 Photons of light “jump” from pigment to pigment until it reaches the Reaction
Center containing chlorophyll a.
 Chlorophyll a – absorbs blue-violet and red light
 Participates directly in the light reactions
 Chlorophyll b – absorbs blue and orange light
 Helps light reactions by increasing the range of light that can be absorbed
 Carotenoids – absorb blue-green light
 Absorb and dissipate excessive light that may damage chlorophyll a
5. Distinguish b/w the locations and products and reactants of the light and dark
reactions (Calvin Cycle) of photosynthesis
 Light Reactions
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Convert solar to chemical energy
Synthesize ATP (energy storage) and NADPH (electron carrier)
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Calvin Cycle (Dark Reactions)
Makes sugar from CO2
Uses ATP and NADPH from light reactions
6. Explain the function of the photosystems and trace electron flow through
photosystems I and II
 Photosystems – have clusters of pigment molecules that act as antennae for
photons of light.
 Next to the reaction center is the primary electron acceptor which traps the light
excited electron energy into ATP or NADPH.
1. Water splitting photosystem –
 Light energy to extract electrons from water
 Releases O2 as a waste product
2. NADPH producing photosystem
 Produces NADPH by transferring light excited electrons from chlorophyll to
NADP
7. Summarize the carbon-fixing reactions of the Calvin Cycle and describe changes
that occur in the carbon skeletons or intermediates
8. Describe the role of ATP and NADPH in the Calvin Cycle
9. Distinguish b/w C3, C4, and CAM pathways, and describe the major
consequences of photorespiration
C3 Plants – use CO2 directly from the air
 EX – soybean, wheat, oats, rice…
 Dry weather can decrease the rate of photosynthesis and crop productivity
because stomata are closed to prevent water loss and no CO2 gas exchange
occurs.
C4 Plants – use an enzyme to incorporate CO2
 EX – corn, sorghum, sugarcane
 Save water without slowing photosynthesis
 When hot the stomata are closed to prevent water loss
 Continues sugar production by using an enzyme to incorporate CO2 into a 4 C
compound instead of the normal 3 C compound.
CAM Plants – opens stomata at night to let in CO2 and to prevent water
loss
 Ex – pineapple, cacti, succulents
 Once the CO2 is inside the leaf it forms a 4 C compound
 Bank CO2 at night and release it to the Calvin Cycle during the day