Anthropology Chapter 3 vocab

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Anthropology Chapter 3 vocab
2013-08-31 21:34:11

Chapter 3 vocabulary
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  1. Protiens
    Three-dimensional molecules that serve a wide variety of functions through their ability to bind to other molecules.
  2. Nucleus
    A structure (organelle) found in all eukaryotic cells. The nucleus contains chromosomes (nuclear DNA).
  3. Molecules
    Structures made up of two or more atoms. Molecules can combine with other molecules to form more complex structures.
  4. DNA
    Deoxyribonucleic Acid
    The double-stranded molecule that contains the genetic code. DNA is a main component of chromosomes.
  5. RNA
    Ribonucleic Acid
    A single-stranded molecule similar in structure to DNA. Three forms of RNA are essential to protein synthesis; messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA).
  6. Cytoplasm
    The semifluid, gel-like substance contained within the cell membrane. The nucleus and numerous structures involved with cell function are found within the cytoplasm.
  7. Protein Synthesis
    The manufacture of proteins; the assembly of chains of amino acids into functional protein molecules. Protein synthesis is directed by DNA.
  8. Mitochondria
    (sing. mitochondrion) Structures contained within the cytoplasm of eukaryotic cells that convert energy, derived from nutrients, to a form that can be used by the cells.
  9. Ribosomes
    Structures composed of a form of RNA called ribosomal RNA (rRNA) and protein. Ribosomes are found in a cell's cytoplasm and are essential to the manufacture of proteins.
  10. Mitochondrial DNA
    DNA found in the mitochondria. Mitochondrial DNA is inherited from the mother.
  11. Somatic Cells
    Basically, all the cells in the body except those involved with reproduction.
  12. Gametes
    Reproductive cells (eggs and sperm in animals) developed from precursor cells in ovaries and testes.
  13. Zygote
    A cell formed by the union of an egg cell and a sperm cell. It contains the full complement of chromosomes (in humans, 46) and has the potential of developing into an entire organism.
  14. Nucleotides
    Basic units of the DNA molecule, composed of a sugar, a phosphate, and one of four DNA bases.
  15. Replicate
    To duplicate. The DNA molecule is able to make copies of itself.
  16. Enzymes
    Specialized proteins that initiate and direct chemical reactions in the body.
  17. Complementary
    In genetics, referring to the fact that DNA bases form pairs (called base pairs) in a precise manner. For example, adenine can bond only to thymine. These two bases are said to be complementary because on requires the other to forma a complete DNA base pair.
  18. Hemoglobin
    A protein molecule that occurs in red blood cells and binds to oxygen molecules.
  19. Hormones
    Substances (usually proteins) that are produced by specialized cells and that travel to other parts of the body, where they influence chemical reactions and regulate various cellular functions.
  20. Amino Acids
    Small molecules that are the components of proteins.
  21. Messenger RNA
    A form of RNA that's assembled on a sequence of DNA bases. It carries the DNA code to the ribosomes during proteins synthesis.
  22. Codons
    Triplets of messenger RNA bases that code for specific amino acids during protein synthesis.
  23. Transfer RNA
    A type of RNA that binds to specific amino acids and transports them to the ribosome during protein synthesis.
  24. Mutation
    A change in DNA. The term can refer to changes in DNA bases (specifically called point mutations) as well as to challenges in chromosome number and/or structure.
  25. Gene
    A sequence of DNA bases that specifies the order of amino acids in an entire protein, a portion of a protein, or any functional product (e.g. RNA). A gene may be made up of hundreds or thousands of DNA bases organized into coding and non-coding segments.
  26. Genome
    The entire genetic makeup of an individual or an entire species. In humans, it's estimated that each individual possesses approximately 3 billion DNA bases.
  27. Noncoding DNA
    DNA that does not direct the production of proteins. However, such DNA segments may produce other important molecules, so the term noncoding DNA is not really accurate.
  28. Exons
    Segments of genes that are transcribed and are involved in protein synthesis. (The prefix ex denotes that these segments are expressed.)
  29. Introns
    Segments of genes that are initially transcribed and then deleted. Because they aren't expressed, they aren't involved in protein synthesis.
  30. Regulatory genes
    Genes that influence the activity of other genes. Regulatory genes direct embryonic development and are involved in physiological processes throughout life. They are extremely important to the evolutionary process.
  31. Homeobox genes
    An evolutionarily ancient family of regulatory genes that directs the development of the overall body plan and the segmentation of body tissues.
  32. Sickle-cell anemia
    A severe inherited hemoglobin disorder in which red blood cells collapse when deprived to oxygen. It results from inheriting two copies of a mutant allele. The type of mutation that produces the sickle-cell allele is a point mutation.
  33. Point mutation
    A change in one of the four DNA bases.
  34. Chromatin
    The form of DNA that is present when a cell is not dividing. Microscopically, chromatin appears as a granular substance; when it condenses prior to cell division, it forms chromosomes.
  35. Chromosomes
    Discrete structures composed of DNA and proteins found only in the nuclei of cells. Chromosomes are visible under magnification only during certain phases of cell division.
  36. Autosomes
    All chromosomes except the sex chromosomes.
  37. Sex chromosomes
    In mammals, the X and Y chromosomes.
  38. Locus
    • (pl., loci) The position or location on a chromosome where a given gene occurs. The term is sometimes used interchangeably with gene.
  39. Alleles
    Alternate forms of a gene. Alleles occur at the same locus on paired chromosomes and thus govern the same trait. But because they're different, their action may result in different expression of that trait.
  40. Karyotype
    The chromosomes of an individual, or what is typical of a species, viewed microscopically and displayed in a photograph.The chromosomes are arranged in pairs and according to size and position of the centromere.
  41. Mitosis
    Simple cell division; the process by which somatic cells divide to produce two identical daughter cells.
  42. Meiosis
    Cell division in specialized cells in ovaries and testes. Meiosis involves two divisions and results in four daughter cells, each containing only half the original number of chromosomes. These cells can develop into gametes.
  43. Recombination
    • The exchange of genetic material between paired chromosomes during meiosis; also called crossing over.
  44. Clones
    Organisms that are genetically identical to another organism. The term may also be sued to refer to genetically identical DNA segments, molecules, or cells.
  45. Random assortment
    The chance distribution of chromosomes to daughter cells during meiosis. Along with recombination, random assortment is an important source of genetic variation (but not new alleles).
  46. Polymerase chain reaction
    A method of producing thousands of copies of a DNA sample.
  47. Human Genome Project
    An international effort aimed at sequencing and mapping the entire human genome, completed in 2003.