Life Science -- Grades 6-8

Classification of Organisms

1. Classify organisms into the currently recognized kingdoms according to characteristics that they share. Be familiar with organisms from each kingdom.

2. Recognize that all organisms are composed of cells, and that many organisms are single-celled (unicellular), e.g., bacteria, yeast. In these single-celled organisms, one cell must carry out all of the basic functions of life.

3. Compare and contrast plant and animal cells, including major organelles (cell membrane, cell wall, nucleus, cytoplasm, chloroplasts, mitochondria, vacuoles).

4. Recognize that within cells, many of the basic functions of organisms (e.g., extracting energy from food and getting rid of waste) are carried out. The way in which cells function is similar in all living organisms.

5. Describe the hierarchical organization of multicellular organisms from cells to tissues to organs to systems to organisms.

6. Identify the general functions of the major systems of the human body (digestion, respiration, reproduction, circulation, excretion, protection from disease, and movement, control, and coordination) and describe ways that these systems interact with each other.

7. Recognize that every organism requires a set of instructions that specifies its traits. These instructions are stored in the organism's chromosomes. Heredity is the passage of these instructions from one generation to another.

8. Recognize that hereditary information is contained in genes located in the chromosomes of each cell. A human cell contains about 30,000 different genes on 23 different chromosomes.

9. Compare sexual reproduction (offspring inherit half of their genes from each parent) with asexual reproduction (offspring is an identical copy of the parent's cell).

10. Give examples of ways in which genetic variation and environmental factors are causes of evolution and the diversity of organisms.

11. Recognize that evidence drawn from geology, fossils, and comparative anatomy provide the basis of the theory of evolution.

12. Relate the extinction of species to a mismatch of adaptation and the environment.

13. Give examples of ways in which organisms interact and have different functions within an ecosystem that enable the ecosystem to survive.

14. Explain the roles and relationships among producers, consumers, and decomposers in the process of energy transfer in a food web.

15. Explain how dead plants and animals are broken down by other living organisms and how this process contributes to the system as a whole.

16. Recognize that producers (plants that contain chlorophyll) use the energy from sunlight to make sugars from carbon dioxide and water through a process called photosynthesis. This food can be used immediately, stored for later use, or used by other organisms.

An asterisk (*) indicates core standards for integrated courses.

1. The Chemistry of Life

Broad Concept: Living things are made of atoms bonded together to form organic molecules.

1.1 Explain the significance of carbon in organic molecules.

1.2 Recognize the six most common elements in organic molecules (C, H, N, O, P, S).

1.3 Describe the composition and functions of the four major categories of organic molecules (carbohydrates, lipids, proteins, and nucleic acids). *

1.4 Describe how dehydration synthesis and hydrolysis relate to organic molecules.

1.5 Explain the role of enzymes in biochemical reactions.

Broad Concept: All living things are composed of cells. Life processes in a cell are based on molecular interactions.

2.1 Relate cell parts/organelles to their functions. *

2.2 Differentiate between prokaryotic cells and eukaryotic cells, in terms of their general structures and degrees of complexity. *

2.3 Distinguish between plant and animal cells. *

2.4 Describe how cells function in a narrow range of physical conditions, such as temperature and pH, to perform life functions that help to maintain homeostasis.

2.5 Explain the role of cell membranes as a highly selective barrier (diffusion, osmosis, and active transport). *

2.6 Identify the reactants and products in the general reaction of photosynthesis. Describe the use of isotopes in this identification.

2.7 Provide evidence that the organic compounds produced by plants are the primary source of energy and nutrients for most living things. *

2.8 Identify how cellular respiration is important for the production of ATP.

2.9 Explain the interrelated nature of photosynthesis and cellular respiration. *

2.10 Describe and compare the processes of mitosis and meiosis, and their role in the cell cycle. *

Broad Concept: Genes are a set of instructions encoded in the DNA sequence of each organism that specify the sequence of amino acids in proteins characteristic of that organism.

3.1 Describe the structure and function of DNA, and distinguish among replication, transcription, and translation. *

3.2 Describe the processes of replication, transcription, and translation and how they relate to each other in molecular biology.

3.3 Describe the general pathway by which ribosomes synthesize proteins by using tRNAs to translate genetic information encoded in mRNAs.

3.4 Explain how mutations in the DNA sequence of a gene may be silent or result in phenotypic change in an organism and in its offspring.

3.5 Differentiate between dominant, recessive, codominant, polygenic, and sex-linked traits.

3.6 State Mendel's laws of segregation and independent assortment.

3.7 Use a Punnett Square to determine the genotype and phenotype of monohybrid crosses. *

3.8 Explain how zygotes are produced in the fertilization process.

3.9 Recognize that while viruses lack cellular structure, they have the genetic material to invade living cells.

Broad Concept: There is a relationship between structure and function in organ systems of humans.

4.1 Explain how major organ systems in humans (e.g., kidney, muscle, lung) have functional units (e.g., nephron, sarcome, alveoli) with specific anatomy that perform the function of that organ system.

4.2 Describe how the function of individual systems within humans are integrated to maintain a homeostatic balance in the body.

Broad Concept: Evolution and biodiversity are the result of genetic changes that occur in constantly changing environments.

5.1 Explain how the fossil record, comparative anatomy, and other evidence support the theory of evolution.

5.2 Illustrate how genetic variation is preserved or eliminated from a population through Darwinian natural selection (evolution) resulting in biodiversity.

5.3 Describe how the taxonomic system classifies living things into domains (eubacteria, archaebacteria, and eukaryotes) and kingdoms (animals, plants, fungi, etc.). * [Note: there is an ongoing scientific debate about the number of kingdoms and which organisms should be included in each.]

Broad Concept: Ecology is the interaction between living organisms and their environment.

6.1 Explain how biotic and abiotic factors cycle in an ecosystem (water, carbon, oxygen, and nitrogen). *

6.2 Use a food web to identify and distinguish producers, consumers, and decomposers, and explain the transfer of energy through trophic levels. *

6.3 Identify the factors in an ecosystem that influence fluctuations in population size.

6.4 Analyze changes in an ecosystem resulting from natural causes, changes in climate, human activity, or introduction of non-native species.

6.5 Explain how symbiotic behavior produces interactions within ecosystems.