| Grade 8: Life Systems: Cells, Tissues, Organs, and Systems |
|
Overall Expectations |
| •demonstrate an understanding of the
basic structure and function of plant and animal cells, and describe the
hierarchical organization of cells in plants and animals; |
| •investigate basic cellular processes and certain specialized
cells in plants; |
| •describe ways in which study of the
structure, function, and interdependence of human organ systems can result
in improvements in human health. |
|
Specific Expectations |
| Understanding Basic Concepts |
| •identify unicellular organisms (e.g.,
amoebae) and multicellular organisms (e.g., worms, humans); |
| •investigate ways in which unicellular
organisms meet their basic needs (e.g., for food, movement); |
| •identify organelles in cells through observation (e.g.,
vacuole, nucleus, chloroplast) and explain their functions; |
| •describe, using their observations, differences in structure
between plant and animal cells; |
| •describe the organization of cells into tissues, organs,
and systems; |
| •explain the function of selectively permeable membranes
in cells; |
| •describe and explain the structure
and function of specialized cells and tissues in different parts of plants
(e.g., in roots, stems, leaves); |
| •recognize that cells in multicellular
organisms need to reproduce to make more cells to form and repair tissues; |
| •explain how the structure of the roots,
stem, and leaves of a plant permit the movement of food, water, and gases; |
| •compare the structure of different
plants (e.g., cactus, coniferous tree, moss) and show how their structure
enables them to live in specific conditions; |
| •describe, using their observations, the movement of gases
and water into and out of cells during diffusion and osmosis. |
| Developing Skills of Inquiry, Design, and Communication |
| •use a microscope accurately to find, observe, and draw
microscopic objects; |
| •formulate questions about and identify needs related
to the functioning of cells, and explore possible answers to these questions
and ways of meeting these needs (e.g., design and conduct an experiment
to test a hypothesis about the effect of chemicals on a unicellular organism;
design and conduct an experiment to test the effectiveness of different
substances in preventing cut flowers from wilting); |
| •plan investigations for some of these answers and solutions,
identifying variables that need to be held constant to ensure a fair test
and identifying criteria for assessing solutions; |
| •use appropriate vocabulary, including correct science
and technology terminology, to communicate ideas, procedures, and results
(e.g., use scientific terms such as organelle, diffusion, osmosis, selectively
permeable); |
| •compile qualitative and quantitative data gathered through
investigation in order to record and present results, using diagrams,
flow charts, frequency tables, graphs, and stem-and-leaf plots produced
by hand or with a computer (e.g., use a diagram to present an estimate
of the number of cells in a petri dish); |
| •communicate the procedures and results of investigations
for specific purposes and to specific audiences, using media works, oral
presentations, written notes and descriptions, charts, graphs, and drawings
(e.g., create a simulation illustrating movement of water and nutrients
between cells and through various organs and systems). |
| Relating Science and Technology to the World Outside
the School |
| •describe the needs and functions of
various cells and organs in relationship to the needs of the human body
as a whole; |
| •describe the basic factors that contribute to the efficient
functioning of the human respiratory, circulatory, digestive, excretory,
and nervous systems; |
| •describe some ways in which the various systems in the
human body are interdependent; |
| •describe similarities and differences
in the functions of comparable structures in different groups of living
things (e.g., compare the food intake and digestion of a unicellular organism,
an invertebrate and a vertebrate); |
| •describe ways in which research about cells has brought
about improvements in human health and nutrition (e.g., development of
medicines, immunization procedures, and diets based on the needs of organs
such as the heart); |
| •describe ways in which substances work by altering the
way cells function (e.g., insulin); |
| •describe ways in which various types of cells contribute
to the healthy functioning of the human body (e.g., red blood cells transport
oxygen throughout the body); |
| •illustrate how blood is pushed by pressure throughout
the body to carry oxygen and nutrients to cells, tissues, and organs. |