Comparing and sorting organisms with similar characteristics into groups based on internal and external structures recognized by scientists.
Recognizing that individuals that can reproduce with one another and produce fertile offspring are classified as a species.
Scientists organize the vast diversity of organisms by describing similarities and differences among living things. Details of internal and external structures of organisms are more important for scientific classification than behavior and general appearance.
Individuals that can reproduce with one another and produce fertile offspring are classified as a species.
Identifying that traits occur randomly.
Explaining that advantageous traits of organisms are passed on through reproduction.
Comparing sexual with asexual reproduction.
Differences in physical characteristics (traits) occur randomly (by chance) in a population or species.
As environments change, organisms that possess advantageous traits (those that enable them to survive) pass those traits to offspring through reproduction.
Explaining how traits are passed on from the instructions of one or more genes that are inherited from the parents.
Every organism requires a set of instructions (genes) for specifying its traits. Heredity is the passage of these instructions from one generation to another.
As a result of sexual reproduction, half of an individual's traits come from one parent, half from the other.
An inherited trait of an individual can be determined by one or by many genes, and a single gene can influence more than one trait.
Predicting, explaining and drawing conclusions about the direction of movement of substances across a membrane.
Developing a model that illustrates the interdependence of cellular organelles (mitochondria, ribosomes, lysosomes, endoplasmic reticulum, cytoplasm) in biochemical pathways within the cell (e.g. mitochondria and chloroplasts: cellular respiration and photosynthesis; nucleus and ribosomes: DNA transcription and protein synthesis).
Explaining how the basic (general) shape and structure of each of the four types of organic molecules relates to its role in maintaining cell survival (i.e., Simple carbohydrates [monosaccharides] can be an energy source as a single molecule and a storage/structural molecule when multiple units are chemically combined-[starch, cellulose, chitin].).
Explaining how a specific sequence of amino acids determines the shape of a protein (i.e., hemoglobin molecule-normal vs. Sickle cell).
There are four basic types of organic compounds found in a cell (proteins, carbohydrates, lipids and nucleic acids).
Enzymes, proteins that regulate biochemical reactions, are critical to the survival of cells.
The molecular structure of a cell membrane allows for selective transfer of substances into and out of the cell (i.e., diffusion, osmosis, facilitated diffusion, active transport).
The shape of proteins in a cell determines the structure and function of that cell, hence survival of the organism (i.e., cytoskeleton, biochemical functions, catalysts).
Creating a model which illustrates how the DNA of all cells/tissues in an organism is produced from a single fertilized egg cell (mitosis).
Explaining how the nucleotide sequence in DNA (gene) directs the synthesis of specific proteins needed by a cell (e.g., protein synthesis) and cell division.
Every body cell in an organism contains the identical genome (DNA) which is maintained from one cell generation to the next by mitosis and DNA replication.
Transmission of genetic information to offspring occurs through egg and sperm cells that contain only one representative from each chromosome pair.
The genetic information in a cell's DNA is used to direct the synthesis of the thousands of proteins that each cell requires, however only portions of the genome are active in any one cell.
Genetic variation in organisms arises from gamete formation and sexual reproduction.
Predicting the change in an embryo caused by disruption of the ectoderm or mesoderm or endoderm during embryonic development (e.g., Fetal Alcohol Syndrome, drugs, injury).
Comparing the role of various sub-cellular units in unicellular organisms to comparable structures in multicellular organisms (i.e., oral groove, gullet, food vacuole in Paramecium compared to digestive systems in multicellular organisms).
Cell differentiation is regulated through the expression of different genes within the embryo cells. During embryonic development of complex multicellular organisms, chemicals within the cells activate and deactivate portions of the genetic code as influenced by the cell's environment and past history.
Unicellular organisms lack differentiation, but sub-cellular units carry out all life functions.
Comparing and contrasting the structure of mitochondria and chloroplasts as cell organelles, the interrelatedness of their functions, and their importance to the survival of all cells.
Describing and justifying a possible flow of energy from the environment through an organism to the cellular level, and through the cell from assimilation through storage in ATP.
Investigating and describing enzyme action under a variety of chemical and physical conditions.
In living systems, energy flows through matter and is stored and released through chemical reactions. Basic survival energy transformations between cells and their environment include aerobic and anaerobic respiration and photosynthesis reactions. Energy is necessary for work to be accomplished and life to be sustained (e.g., At the cellular level, this work can be growth, repair, reproduction, and synthesis).
Energy is stored in living systems in ATP molecules. Energy is transformed through living systems from the environment through specific cell organelles and specific chemical processes.
Energy transformations in living systems are enzyme dependent.
Developing a graphic representation that illustrates and compares the degree of molecular similarity among several species (e.g., DNA or amino acid sequences).
Formal classification systems of organisms (Domain, Kingdom, Phylum...) are based upon molecular similarities and differences among organisms.
A species is the most fundamental unit of classification. Similarity of species (degree of kinship) can be substantiated by the molecular composition (e.g., DNA /amino acid sequences, biochemical similarity within species).
Using evidence to apply the theory of Natural Selection to a scenario depicting change within a given population over time/through many generations (e.g., bacterial resistance to antibiotics, neck length of the giraffe, animal camouflage).
The diversity of present-day organisms resulted from changes over time in many ancestral organisms.
Evolution (change over time) is based on variety within species. A greater variation within a species increases the possibility of species survival under changing conditions. Life on earth is thought to have begun four billion years ago, as simple, one-celled organisms about some of which still exist today.
Natural Selection provides a mechanism for evolution and leads to organisms well-suited in a particular, existing environment.
genetic variability of offspring
a finite supply of resources, producing stress and competition
the selection (survival and subsequent reproduction) of offspring best suited to a particular environment
Molecular structure provides additional evidence for evolution.
Modeling and explaining how the structure of DNA is maintained and relates to genes and chromosomes, which code for specific protein molecules within a cell.
Modeling or diagramming new gene combinations that result from sexual reproduction (e.g., dominant/recessive traits).
Explaining how alteration of a DNA sequence may affect physical/chemical characteristics of the human body (e.g., sickle-cell anemia, cancer genetic engineering).
Comparing and contrasting the chromosome content of somatic cells and that of sex cells (gametes).
Instructions for specified characteristics of an organism are carried in DNA. (NSES) The information passed from parents to offspring is coded in DNA molecules. DNA molecules are long chains linking just four kinds of smaller molecules, whose sequence encodes genetic information.
The human body is formed from cells that contain homologous parts two copies of each chromosome.
New heritable characteristics can result from new combinations of existing genes or from mutations of genes in reproductive cells.
The sorting and recombination of genes in sexual reproduction results in a great variety of possible gene combinations (Include value of meiosis, but not phases).
Some new gene combinations make little difference, some can produce organisms with new and perhaps enhanced capabilities and some can be deleterious.
Gene mutations can be caused by radiation and chemicals (legal and illegal) and are passed on to offspring when they occur in sex cells.
Inserting, deleting or substituting DNA segments can alter genes.
Changes in DNA (mutations) occur spontaneously at low rates, but can affect the organism in many ways or may go unnoticed.
Gene mutations in a cell can result in uncontrolled division called cancer. Exposure of cells to certain chemicals and radiation increases mutations and thus chances of cancer.