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STUDENTS SHOULD
KNOW
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EXAMPLES OF WHAT
STUDENTS SHOULD BE ABLE TO DO
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Biochemistry
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1. A living cell is mainly composed
of a small number of chemical elements, mainly carbon,
hydrogen, nitrogen, oxygen, phosphorous, and sulfur. Carbon,
because of its small size and four available bonding
electrons, can join to other carbon atoms in chains and
rings to form large and complex molecules. (AKSci - A.1
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• Debate the existence of life
without water or carbon.
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2. Complex carbon-based molecules,
including proteins, lipids, carbohydrates, and nucleic
acids, comprise the primary building blocks of all living
things. (AKSci - A.1)
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• Build models of molecules
given either structural or empirical formulas.
• Blend a typical fast food
meal (burger, fries, and soda) and analyze for
carbohydrates, fat, and protein by using the appropriate lab
tests.
• Relate structure to physical
properties by using a taste test of different
sugars.
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3. The work of the cell is carried
out by the many different types of molecules it assembles,
mostly proteins. Protein molecules are long, usually folded
chains made from a combination of up to 20 different kinds
of amino-acid molecules. The function of each protein
molecule depends on its specific sequence of amino acids and
the shape the chain takes is a consequence of attractions
between the chain's parts. (AKSci - A.10)
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• Select an enzyme substrate
system (e.g., catalase/hydrogen peroxide, amylase/starch,
protease/gelatin) and investigate factors that affect the
rate of enzyme catalyzed reaction (e.g., temperature, pH,
enzyme/substrate concentration). Relate the results of the
investigation to the need for maintaining a narrow pH and
temperature range in human bodies.
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Cell Biology
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1. Within the cell are specialized
parts for the transport of materials, energy capture and
release, protein building, waste disposal, information
feedback, and even movement. In addition to these basic
cellular functions common to all cells, most cells in
multicellular organisms perform some special functions that
others do not. (AKSci - A.10)
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• Create generic models
representative of plant, animal, and microorganisms from
direct observation or other resources, to illustrate the
difference between cells from the representative
kingdoms.
• Explain that plants and
animals all produce a gas during respiration.
• Demonstrate yeast
respiration by using yeast, molasses and gas
tubes.
• Demonstrate the importance
of light for photosynthesis (e.g., by putting a light screen
over geranium leaves) and relate the differing results of
subsequent iodine tests for carbohydrates to the plant's
growth environments.
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2. Every cell is covered by a
membrane that controls what can enter and leave the cell. In
all but quite primitive cells, a complex network of proteins
provides organization and shape and, movement. (AKSci -
A.10)
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• Construct cell models (e.g.,
phenolphthalein-agar cubes and potato-iodine cubes) to
investigate the relationship among cell size, surface to
volume ratio and the rates of diffusion into and out of the
cell.
• Speculate why large
organisms have developed from many small cells rather than
from one lone cell.
• Simulate digestion in a
beaker (use for example, dialysis tubing, water, starch,
iodine, and amylase) and explain the results.
• Investigate the effect of
concentration gradients on the movement of materials across
cell membranes.
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3. The many body cells in an
individual can be very different from one another, even
though they are all descended from a single cell and thus
have essentially identical genetic instructions. Different
parts of the instructions are used in different types of
cells, influenced by the cell's environment and past
history. (AKSci - A.10)
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• Conduct investigations to
observe and describe the changes which take place in a plant
seed as it develops into a mature plant and determine how
development is affected by internal and external factors,
e.g., auxins, nutrients, light.
• Observe and describe changes
that occur during the development of animals. Explain how
environmental factors affect development.
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4. In multicellular organisms,
including humans, cells perform specialized functions as
parts of sub-systems (e.g., tissues, organs, and organ
networks) which work together to maintain optimum conditions
for the benefit of the whole organism. Function is related
to structure. (AKSci - A.10)
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• Describe and illustrate how
vertebrates, including humans, carry on life processes
(e.g., obtaining energy, protection, regulation,
reproduction).
• Classify animal skulls as
omnivores, herbivores, or carnivores.
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5. Coordination of these functions
is accomplished by specialized cells or groups of cells that
monitor stimuli from the organism's internal and external
environment enabling the organism to respond to changing
environmental conditions. (AKSci - A.10)
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• Culture bacteria using
differential media to demonstrate the limitation of
adaptation, such as their pH tolerance range.
•Design and construct an
experiment through which they can explore the learning
behavior of an organism, such as a planarian.
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Genetics
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1. The genetic information passed
from parents to offspring is coded in DNA molecules. (AKSci
- A.11)
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• Extract DNA from onion
cells.
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2. The genetic information in DNA
molecules provides instructions for assembling protein
molecules. The code used is virtually the same for all life
forms. (AKSci - A.10, A.11)
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• Use models to describe the
structure of DNA and explain the process whereby DNA directs
the synthesis of proteins from amino acids. Relate the
structure of a particular protein such as hemoglobin to the
function it performs, noting how errors in amino acid
sequencing alters the function.
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3. The similarity of human DNA
sequences and the resulting similarity in cell chemistry and
anatomy identify human beings as a single species. (AKSci -
A.11)
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• Discuss the difficulty of
defining a species and explain the biological meaning of
species, e.g., the constant reclassification of some bird
species.
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4. The sorting and recombination of
genes in sexual reproduction results in countless possible
gene combinations from the offspring of any two parents.
(AKSci - A.11)
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• Use prepared slides and
models of plant and animal cell mitosis to describe changes
that occur during the cell cycle.
• Use models of plants and
animal cell meiosis to describe the major events that occur
during the reduction division process that forms gametes.
Discuss why the number of chromosomes in gametes is one half
the chromosome number in body cells.
• Culture fungi (e.g.,
Sordaria) under different conditions to demonstrate both its
sexual and asexual life cycles.
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5. Genes are segments of DNA
molecules. Inserting, deleting, or substituting DNA segments
can alter genes. An altered gene may be passed on to every
cell that develops from it. The resulting features may help,
harm, or have little or no effect on the offspring's success
in its environment. (AKSci - A.11)
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6. Gene mutations can be caused by
such things as radiation and chemicals. When they occur in
sex cells, the mutations can be passed on to offspring; if
they occur in other cells, they can be passed on to
descendant cells only. The experiences an organism has
during its lifetime can affect its offspring only if the
genes in its own sex cells are changed by the experience.
(AKSci - A.11)
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• Identify several causes of
mutations and distinguish between beneficial, harmful, and
neutral mutations. Explain why exposures to mutagens such as
UV light and X-rays should be limited to prevent gene
mutation.
• Use models of DNA, RNA,
amino acids, etc., to demonstrate how mutations affect the
structure of proteins, Relate the structural change in the
protein to the alteration of a trait; for example,
sickle-cell disease is caused by a singe DNA base
substitution that affects the structural configuration of
hemoglobin molecules found in red blood cells.
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7. After the publication of Origin
of Species, biological evolution was supported by the
rediscovery of the genetics experiments of an Austrian monk,
Gregor Mendel, by the identification of genes and how they
are sorted in reproduction, and by the discovery that the
genetic code found in DNA is the same for almost all
organisms. (AKSci - C.5, C.6, C.7)
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• Use Punnet squares and
pedigree charts to determine probabilities and patterns of
inheritance of traits such as seed shape in pea plants,
flower color in snapdragons, and blood type and color
blindness in humans.
• After using fruit flies,
"Fast Plants", or computer software to derive Mendel's Laws
of segregation and independent assortment, the students are
able to compare and contrast their empirical results with
Mendelian ratios.
• Construct a timeline showing
the development of genetic principles from Mendel to the
present by examining historical documents.
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Hot Topics
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1. Current biological issues relate
to the science of biology (i.e., drugs, alcohol, HIV,
smoking, cloning) (AKSci - D.1, D.2, D.3, D.4, D.5, D.6
-depending on project)
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• Simulate the spread of a
communicable disease and determine the original source of
the disease.
• Debate the fairness of
adjusted insurance rates for smokers versus
non-smokers.
• Discuss the economic and
ecological impacts of such topics as Spruce Bark Beetle
infestation, bottom fishing, endangered species,
etc.
• Select a pertinent
bioethical issue (e.g., manipulating genetic material, in
vitro fertilization, use of human growth hormone) and debate
the benefits and risks associated with its
development.
• Use models or laboratory
procedures to understand the process of inserting DNA from
one organism into the genetic make-up of another organism.
Discuss the applications of recombinant DNA technology and
the economic implications of allowing organisms created by
biotechnology (e.g., genetically engineered frost-resistant
plants, human growth hormone, and insulin) to be
patented.
• Justify a position regarding
the use of genetic counseling information for family
planning.
• Examine a DNA profile,
produced by gel electrophoresis, or participate in a
simulation activity to identify and compare the DNA
"fingerprint" in different samples of DNA. Discuss how DNA
fingerprinting is used in criminal trials, cases of disputed
parentage, and genetic screening for disease.
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Diversity of Life
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1. The basis of biological
evolutionary theory is that the earth's present-day species
developed from earlier, distinctly different species. (AKSci
- A.13)
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2. Evolution builds on what already
exists, so the more variety there is, the more there can be
in the future. But evolution does not imply long-term
progress in some set direction. Evolutionary changes appear
to be like the growth of a bush: some branches survive from
the beginning with little or no change, many die out
altogether, and others branch repeatedly, sometimes giving
rise to more complex organisms. (AKSci - A.13)
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• Gather data, summarize
findings, and present critical analysis of evolution on the
basis of anatomical and molecular characteristics and other
evidence.
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3. Natural selection provides the
scientific explanation for the history of life on earth as
depicted in the fossil record and in the similarities
evident within the diversity of existing organisms. (AKSci -
A.13)
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• Analyze successes and
failures in terms of natural selection, genetic variation,
speciation and adaptation, after using computer simulation
software to design plants and animals, and test their
survival in various environments.
• Research an extinct organism
to discover the environmental pressures that may have
contributed to its demise.
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4. Natural selection provides the
following mechanism for evolution: Some variation in
heritable characteristics exists within every species, some
of these characteristics give individuals an advantage over
others in surviving and reproducing, and the advantaged
offspring, in turn, are more likely than others to survive
and reproduce. The proportion of individuals that have
advantageous characteristics will increase. (AKSci - A.13)
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• Identify the benefits and
risks associated with the widespread use of antibiotics to
treat infectious diseases in humans and
livestock.
• Participate in natural
selection simulation activities to determine how
environmentally favored traits are perpetuated over
generations, while less favorable traits decrease in
frequency. Discuss the relationship and significance of
genetic variation, natural selection, and the ability to
reproduce.
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5. The variation of organisms
within a species increases the likelihood that at least some
members of the species will survive under changed
environmental conditions, and a great diversity of species
increases the chance that at least some living things will
survive in the face of large changes in the environment.
(AKSci - A.12)
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• Conduct a laboratory
investigation or a simulation to demonstrate that variations
within a species may enable organisms to survive large-scale
environmental change. Examples could include exposure of
bacteria to UV radiation or aquatic organisms to
chlorine.
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6. Molecular evidence substantiates
the anatomical evidence for evolution. Additional detail
about the sequence in which various lines of descent
branched off from one another and the degree of kinship
between organisms or species can be estimated from the
similarity of their DNA sequences. (AKSci - A.13)
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• Use a data table showing the
differences in amino acid sequences of a molecule (e.g.,
cytochrome C or hemoglobin) found in a variety of species,
and correlate the number of amino acid sequence differences
with the probable, evolutionary distance of their
relationship.
• Use gel electrophoresis or
data from to determine the genetic divergence and
evolutionary relationship among species of plants and
animals.
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7. Life on earth is thought to have
begun as simple, one-celled organisms about 4 billion years
ago. During the first 2 billion years, only single-cell
microorganisms existed, but once cells with nuclei
developed, increasingly complex multicellular organisms
evolved. (AKSci - A.13)
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• Create a timeline of Earth's
history.
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8. Organisms are classified into a
hierarchy of groups and subgroups, based on structural
similarities and evolutionary relationships. (AKSci - A.10,
A.13)
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• Use a taxonomic key to
classify different species of trees and suggest possible
evolutionary links between species.
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Ecology
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1. The amount of life any
environment can support is limited by the available energy,
water, oxygen, and minerals, and by the ability of
ecosystems to recycle the residue of dead organic materials.
(AKSci - A.9)
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• Construct diagrams or flow
charts to show how nutrients and minerals are cycled
throughout the living and non-living parts of an ecosystem.
Discuss how the cycling of Earth's resources provides living
organisms with the chemicals needed to carry out life's'
processes.
• Design and conduct an
experiment to test the effects of soil mineral deficiency or
hormones on plant germination and growth.
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2. The chemical elements that make
up the molecules of living things pass through food webs and
are combined and recombined in different ways. At each link
in a food web, some energy is stored in newly made
structures but much is dissipated into the environment as
heat. Continual input of energy from sunlight keeps the
process going. (AKSci - A.9)
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• Diagram a food chain that
includes sun , plants, primary consumers, the frog and the
dermestid beetles, after observing dermestid beetles
decomposing a frog carcass.
• Create a "Bottle Biology"
habitat for plants and animals, identify the biotic and
abiotic factors in their habitat, and explain their
interactions.
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3. At times, environmental
conditions are such that plants and marine organisms grow
faster than decomposers can recycle them back to the
environment. Layers of energy-rich organic material have
been gradually turned into great coal beds and oil deposits
by the pressure of the overlying earth. By burning these
fossil fuels, stored energy is passed back into the
environment as heat and releasing large amounts of carbon
dioxide. (AKSci - A.9)
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• Identify a commonly used
resource. Research the methods used to obtain the resource,
and the impact the removal of the resource has on the
biogeochemical cycles of an ecosystem.
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4. Ecosystems can be reasonably
stable over hundreds or thousands of years. As any
population of organisms grows, it is held in check by one or
more environmental factors: depletion of food or nesting
sites, increased loss to increased numbers of predators, or
parasites. If a disaster such as flood or fire occurs, the
damaged ecosystem is likely to recover in stages that
eventually result in a system similar to the original one.
(AKSci - A.14a, A.14c)
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• Predict the population
growth curve over time assuming no hunting pressure or
predation of moose in Alaska by using a theoretical
model.
• Identify evidence of intra-
and interspecies interactions among plants and animals
(e.g., competition, predation, parasitism, symbiosis, social
behavior) in an environment.
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5. Human beings are part of the
earth's ecosystems. Human activities do, deliberately or
inadvertently, alter the equilibrium in ecosystems. (AKSci -
A.14a, A,14b, A.14c, D.2)
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• Test a local water source
for nitrate and phosphate pollution associated with
fertilizer use, and investigate the consequences of such
pollution.
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6. Ecosystems and the biosphere can
be stable but currently are NOT. We are now more unstable
than the biosphere has been in 70 million years. (AKSci -
A.14a, A,14b, A.14c, D.2)
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• Explore why biodiversity is
considered a non-renewable resource and discuss the
consequences that result from the reduction of
biodiversity.
•Select a local, pertinent
environmental issue and participate in an activity which
addresses this issue (e.g. beach clean up, stream watch,
adopt-a-highway, salmon census).
• Use computer simulation
software to design an environment and test the effects of
biotic and abiotic factors, analyze successes and failures
in terms of population ecology and ecosystem
dynamics.
• Examine a major road
crossing to determine its direct and indirect impacts on the
local environment. Include in your discussion the effect on
local animal and plant populations and on ground water and
air quality.
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