Cells, Organisms, and Population I nteract

1. Cells, Organisms, and Population Interact Big Idea #4

2. Components of a polymer determine the function Cells, Organisms, and Population Interact Movement of energy through the trophic levels Cell interact within a multicellular organism Molecules interact together Environmental factors influence the expression of genes Organisms interact with external stimuli The structure and function of subcellular components process together in a variety of functions Interactions can be advantageous Organisms interact together in symbiotic relationships Distribution of ecosystems change over time Cell organelles interact together to function

3. The subcomponents of biological molecules and their sequence determine the properties of that molecule. • Nucleic Acid- made of nucleotides (5-Carbon sugar, phosphate, and N base) • Proteins (polypeptides)- made of amino acids, structure and sequence determine function (primary, secondary, tertiary, quaternary). • Phospholipids- polar/nonpolar • Carbohydrates- made on monosaccharide (cellulose and starch)

4. The structure and function of subcellular components, and their interactions, provide essential cellular processes.

6. Interactions between external stimuli and regulated gene expression result in specialization of cells, tissues and organs. • Differentiation in development is due to external and internal cues that BIND to DNA and trigger gene expression • Structural and functional differences of cells in specific tissues is due to expression of specific genes (liver cells use liver genes to function) • The environment can affect gene expression (to much sun)

7. Organisms exhibit complex properties due to interactions between their constituent parts. • Interactions between organs • Stomach and intestines function together for digestion • Root, stem, and leaf • Interactions between systems • Respiratory and circulatory system • Nervous and muscular

8. Communities are composed of populations of organisms that interact in complex ways. • Community is based on species composition and diversity

9. Population growth Exponential Growth Organisms die because of DENSITY Independent factors Logistic Growth Organisms die because of DENSITY dependent factors Competition for resources, territory,

11. Interactions among living systems and with their environment result in the movement of matter and energy. • Energy flows, but matter is recycled • Changes in climates influence primary productivity • Food webs/food chains show interaction Can you think of adaptations for obtaining and using energy?

12. Human populations have increased and impacts on habitats have magnified. This has reduced the population size of many other species because of habitat destruction.

13. Interactions between molecules affect their structure and function. • Changes in structure of a molecule may result in change in function • ENZYME shape, active site, and interaction is important for function • For a reaction to occur the substrate must fit into the active site • Cofactors and coenzymes are present and bind to sites on the enzyme

14. Competitive inhibition/ noncompetitive inhibition • What 2 ways could you measure the rate of product?

15. Cooperative interactions within organisms promote efficiency in the use of energy and matter. • Organisms have areas that perform functions related to energy and matter that contribute to the whole • Eukaryotes have organelles; prokaryotes use the cell membrane and cytoplasm • In multicellular organisms- exchanges of gases, circulation of fluids, excretion of waste • Cells of a population lead to increased efficiency and utilization of matter. • Bacteria in rumen of animals, bacteria in deep sea vents

16. Interactions between and within populations influence patterns of species distribution and abundance. • Interactions between populations affect distributions and abundance • Relationships can be negative or positive • Feedback control systems play a role in these ecosystems

17. Distribution of local and global ecosystems changes over time. • Human impact accelerates change at local and global levels. • Geological and meteorologicalevents impact ecosystem distribution.

18. Variation in molecular units provides cells with a wider range of functions. • Variations within molecular classes provide cells and organisms with a wider range of functions • Phospholipids in cell membrane • Hemoglobin • MHC proteins • Chlorophylls • Multiple copies of alleles or genes (gene duplication) may provide new phenotypes • Heterozygote may be more advantageous • Gene duplication- one of the genes evolves to a new function (antifreeze gene)

19. Environmental factors influence the expression of the genotype in an organism. • Environmental factors influence traits • Flower color based on soil pH, sex determination in reptiles,

20. The level of variation in a population affects population dynamics. • Population ability to respond to changes in the environment is affected by genetic diversity. Species and populations with little genetic diversity are at risk for extinction. • Potato blight • Genetic diversity allows individuals in a population to respond differently to the same changes in environmental conditions. • not all are affected by a disease • Hardy-Weinberg equation models this

21. The diversity of species within an ecosystem may influence the stability of the ecosystem. • Natural and artificial ecosystems with fewer component parts and with little diversity among the parts are often less resilient to changes • Keystone species, producers, and essential abiotic and biotic factors contribute to maintaining the diversity of an ecosystem. The effects of keystone species on the ecosystem are disproportionate relative to their abundance in the ecosystem, and when they are removed from the ecosystem, the ecosystem often collapses.