science

• Cell


  Basic unit of all living matter (Adult = over 10 trillion cells)
• Nucleus


  Central point of cell / contains genetic coding for maintaining life systems and issuing commands for growth & reproduction
• Cytoplasm


  Substance of a cell outside of the nucleus
• Chromosomes


  46 in each Nucleus (23 pairs)
• Genes


  Bands on chromosomes (thousands of genes)
• DNA

  On genes (billions of DNA)
• All living things contain genetic material that serves as the set of instructions that direct the activities and functions of cells
• These genetic materials, also known as DNA(deoxyribonucleic acid), are passed on from one generation to the next
• In eukaryotic cells (cells with organelles), the DNA are bound with proteins and are organized as beads on strings to form chromosomes
• Cell cycle


  Once a cell is fully grown, it either stops growing or divides and produces more cells through a process called CELLULAR REPRODUCTION
• Cellular reproduction helps your body grow and repair worn-out tissues
• Interphase

  The period that follows one cell division and precedes another, during this stage the cell does not divide; it merely grows
• Cell division


  Where the chromosomes become condensed or thickened
• First gap period or G1

  Formation of new cell until it begins to replicate its DNA, the cell grows initially
• Synthesis stage or S


  The middle stage of interphase, period of DNA synthesis or replication
• Second gap period or G2

  Represents a period of rapid cell growth to prepare for cell division
• During Interphase, the nucleus is clearly visible as a distinct membrane bound organelle. On the other hand, the chromosomes cannot be clearly seen. They appear as irregular mass that is grainy appearance because the DNA they contain are stretched out thinly in the nucleus
• Mitosis


  The process of cell division which results in the production of two daughter cells from a single parent cell, two identical cells with the same number of chromosomes
• Mitosis


  1. Interphase

  2. Prophase

  3. Metaphase

  4. Anaphase

  5. Telophase & Cytokinesis
• Interphase


  • Cell preparing to divide, DNA replicated, Organelles replicated, Cell increases in size
• Prophase


  • Chromosomes thicken and shorten, Centrioles move to opposite sides of nucleus, Spindle fibers form, Nucleolus disappears, Nuclear membrane disintegrates
• Metaphase


  • Nuclear membrane disappears, Chromosomes arrange at equator of cell, Chromosomes attach to spindle fibers by centromeres, Spindle fibers bind to kinetochore protein at centromere
• Anaphase


  • Spindle fibers contract pulling chromatids to opposite poles of the cell
• Telophase


  • Chromosomes uncoil, Spindle fibers disintegrate, Centrioles replicate, Nuclear membrane forms, Cell divides (cytokinesis)
• Marginal utility


  The additional utility (satisfaction) gained from the consumption of an additional product
• If you add up marginal utility for each unit you get total utility
• Meiosis


  The type of cell division by which germ cells (eggs and sperm) are produced, One parent cell produces four daughter cells, Daughter cells have half the number of chromosomes found in the original parent cell
• Meiosis I


  1. Prophase 1

  2. Metaphase 1

  3. Anaphase 1

  4. Telophase 1
• Meiosis II


  1. Prophase 2

  2. Metaphase 2

  3. Anaphase 2

  4. Telophase 2
• Crossing-over or the exchange of genetic material between homologous chromosomes can occur in Meiosis I (not in Mitosis)
• Differences between Mitosis and Meiosis

  • Mitosis: Asexual, Cell divides once, Two daughter cells, Genetic information is identical
  • Meiosis: Sexual, Cell divides twice, Four haploid daughter cells, Genetic information is different
• mechanical waves require a medium to travel through
• MOUTH


  Entry point for food
• ESOPHAGUS


  Food tube to the stomach
• LIVER


  Metabolism and bile production
• GALLBLADER


  Bile storage
• STOMACH


  Digestive organ
• PANCREASE


  Enzyme and insulin production
• LARGE INTERTINE


  Water absorption
• SMALL INTESTINE


  Nutrient absorption