
Focus on Life Science
Cell Biology
- All living organisms are composed of cells, from just one
to many trillions, whose details usually are visible only through
a microscope. As a basis for understanding this concept:
- Students know cells function similarly in all
living organisms.
- Students know the characteristics that distinguish
plant cells from animal cells, including chloroplasts and
cell walls.
- Students know the nucleus is the repository for
genetic information in plant and animal cells.
- Students know that mitochondria liberate energy
for the work that cells do and that chloroplasts capture
sunlight energy for photosynthesis.
- Students know cells divide to increase their
numbers through a process of mitosis, which results in two
daughter cells with identical sets of chromosomes.
- Students know that as multicellular organisms
develop, their cells differentiate.
Genetics
- A typical cell of any organism contains genetic instructions
that specify its traits. Those traits may be modified by environmental
influences. As a basis for understanding this concept:
- Students know the differences between the life
cycles and reproduction methods of sexual and asexual organisms.
- Students know sexual reproduction produces offspring
that inherit half their genes from each parent.
- Students know an inherited trait can be determined
by one or more genes.
- Students know plant and animal cells contain
many thousands of different genes and typically have two
copies of every gene. The two copies (or alleles) of the
gene may or may not be identical, and one may be dominant
in determining the phenotype while the other is recessive.
- Students know DNA (deoxyribonucleic acid) is
the genetic material of living organisms and is located
in the chromosomes of each cell.
Evolution
- Biological evolution accounts for the diversity of species
developed through gradual processes over many generations. As
a basis for understanding this concept:
- Students know both genetic variation and environmental
factors are causes of evolution and diversity of organisms.
- Students know the reasoning used by Charles Darwin
in reaching his conclusion that natural selection is the
mechanism of evolution.
- Students know how independent lines of evidence
from geology, fossils, and comparative anatomy provide the
bases for the theory of evolution.
- Students know how to construct a simple branching
diagram to classify living groups of organisms by shared
derived characteristics and how to expand the diagram to
include fossil organisms.
- Students know that extinction of a species occurs
when the environment changes and the adaptive characteristics
of a species are insufficient for its survival.
Earth and Life History (Earth Sciences)
- Evidence from rocks allows us to understand the evolution
of life on Earth. As a basis for understanding this concept:
- Students know Earth processes today are similar
to those that occurred in the past and slow geologic processes
have large cumulative effects over long periods of time.
- Students know the history of life on Earth has
been disrupted by major catastrophic events, such as major
volcanic eruptions or the impacts of asteroids.
- Students know that the rock cycle includes the
formation of new sediment and rocks and that rocks are often
found in layers, with the oldest generally on the bottom.
- Students know that evidence from geologic layers
and radioactive dating indicates Earth is approximately
4.6 billion years old and that life on this planet has existed
for more than 3 billion years.
- Students know fossils provide evidence of how
life and environmental conditions have changed.
- Students know how movements of Earth's continental
and oceanic plates through time, with associated changes
in climate and geographic connections, have affected the
past and present distribution of organisms.
- Students know how to explain significant developments
and extinctions of plant and animal life on the geologic
time scale.
Structure and Function in Living Systems
- The anatomy and physiology of plants and animals illustrate
the complementary nature of structure and function. As a basis
for understanding this concept:
- Students know plants and animals have levels
of organization for structure and function, including cells,
tissues, organs, organ systems, and the whole organism.
- Students know organ systems function because
of the contributions of individual organs, tissues, and
cells. The failure of any part can affect the entire system.
- Students know how bones and muscles work together
to provide a structural framework for movement.
- Students know how the reproductive organs of
the human female and male generate eggs and sperm and how
sexual activity may lead to fertilization and pregnancy.
- Students know the function of the umbilicus and
placenta during pregnancy.
- Students know the structures and processes by
which flowering plants generate pollen, ovules, seeds, and
fruit.
- Students know how to relate the structures of
the eye and ear to their functions.
Physical Principles in Living Systems (Physical Sciences)
- Physical principles underlie biological structures and functions.
As a basis for understanding this concept:
- Students know visible light is a small band within
a very broad electromagnetic spectrum.
- Students know that for an object to be seen,
light emitted by or scattered from it must be detected by
the eye.
- Students know light travels in straight lines
if the medium it travels through does not change.
- Students know how simple lenses are used in a
magnifying glass, the eye, a camera, a telescope, and a
microscope.
- Students know that white light is a mixture of
many wavelengths (colors) and that retinal cells react differently
to different wavelengths.
- Students know light can be reflected, refracted,
transmitted, and absorbed by matter.
- Students know the angle of reflection of a light
beam is equal to the angle of incidence.
- Students know how to compare joints in the body
(wrist, shoulder, thigh) with structures used in machines
and simple devices (hinge, ball-and-socket, and sliding
joints).
- Students know how levers confer mechanical advantage
and how the application of this principle applies to the
musculoskeletal system.
- Students know that contractions of the heart
generate blood pressure and that heart valves prevent back flow
of blood in the circulatory system.
Investigation and Experimentation
- Scientific progress is made by asking meaningful questions
and conducting careful investigations. As a basis for understanding
this concept and addressing the content in the other three strands,
students should develop their own questions and perform investigations.
Students will:
- Select and use appropriate tools and technology (including
calculators, computers, balances, spring scales, microscopes,
and binoculars) to perform tests, collect data, and display
data.
- Use a variety of print and electronic resources (including
the World Wide Web) to collect information and evidence
as part of a research project.
- Communicate the logical connection among hypotheses, science
concepts, tests conducted, data collected, and conclusions
drawn from the scientific evidence.
- Construct scale models, maps, and appropriately labeled
diagrams to communicate scientific knowledge (e.g., motion
of Earth's plates and cell structure).
- Communicate the steps and results from an investigation
in written reports and oral presentations.