Everything Is Connected & Needs Energy

1. Everything Is Connected & Needs Energy LIVING THINGS & CELLS

2. IT’S ALIVE—OR IS IT? Or THE BASIC UNITS OF LIFE Eco

3. KEY TERMS . . . • CELL • STIMULUS • HOMEOSTASIS • REPRODUCTION • HEREDITY • METABOLISM • DECOMPOSER • PHOSPHOLIPID • NUCLEIC ACIDS • CELL MEMBRANE • ORGANELLE • NUCLEUS • PROKARYOTES • EUKARYOTE • CELL WALL • MITOCHONDRIA • CHLOROPLAST • STRUCTURE • FUNCTION

4. CELL A microscopic structure containing genetic material enclosed within a semipermeable membrane and, in plants, a cell wall; the basic structural unit of all organisms.

6. stimulus Something that can evoke a physiological response in a cell, a tissue, or an organism; can be internal or external (sense organs are sensitive to external stimuli).

7. HOMEOSTASIS The tendency of a system to maintain stable internal conditions under fluctuating environmental stimulus that would tend to disturb its normal function.

8. REPRODUCTION The natural process among organisms by which new individuals are generated and the species perpetuated.

9. HEREDITY The transmission from one generation to another of genetic factors that determine individual characteristics; responsible for the resemblances between parents and offspring.

10. METABOLISM The sum total of the chemical processes that occur in living organisms, resulting in growth, production of energy, elimination of waste material, etc.

11. DECOMPOSER An organism, usually a bacterium or fungus, that breaks down the cells of dead plants and animals into simpler substances.

12. PHOSPHOLIPID The

13. NUCLEIC ACIDS Any of a group of very large nucleotides that constitute the genetic material of living cells and that code for the amino acid sequences of proteins.

14. Cell membrane The thin membrane that forms the outer surface of a cell and regulates the passage of materials in and out of the cell.

15. organelle A specialized part of a cell having some specific function (a cell organ).

16. nucleus A large, spherical membrane-bound structure within a living cell, containing the cell’s hereditary material (DNA) and controlling its metabolism, growth, and reproduction.

17. prokaryotes A wide variety of unicellular organisms constituting the bacteria and cyanobacteria, characterized by the absence of a nucleus, no organelles, and by DNA that is not organized into chromosomes.

18. eukaryote Any organism having a cell type that contains specialized organelles in the cytoplasm, a membrane-bound nucleus enclosing genetic material organized into chromosomes, characteristic of all life forms except bacteria.

19. cell wall The rigid outermost layer of cells in plants, bacteria, fungi, and many algae that gives shape to the cell and protects it from infection; In plants, the cell wall is made up mostly of cellulose, determines tissue texture, and often is crucial to cell function.

20. mitochondria An organelle in the cytoplasm of all cells except bacteria in which food molecules are broken down in the presence of oxygen and converted to energy in the form of ATP.

21. chloroplast An organelle in the cells of green plants that contains chlorophyll and creates glucose through photosynthesis.

22. structure The arrangement of particles or parts in a definite pattern of organization (dominated by the general character of the whole) as they relate to each other; the arrangement of formation of the tissues, organs, or other parts of an organism.

23. function Any of a group of related actions contributing to a larger action; the normal and specific contribution of a bodily part to the economy of a living organism (vital function).