unit 5- cells

• Unicellular


  Algae, bacteria, yeast
• Multicellular


  Animals, plants, fungi
• Cell Theory


  • Cells are structure and function in all organisms
  • All cells stem from preexisting cells
• Electron microscope


  Reveals tiniest cell parts in non-living cells only
• On average, cells are 10-20 micrometers
• Prokaryotes


  • Any bacteria
  • Found everywhere
  • Unicellular
  • No nucleus
• Eukaryotes


  • More complex
  • Animals, plants, fungi
  • Many parts = advantageous
  • Presence of nucleus
  • Nucleus= membrane-bound structure that has DNA
• Nucleoid


  The nuclear region of a prokaryotic cell. Where the chromosome is attached to the plasma membrane
• Plasma


  Circular DNA molecules in prokaryotic cells. Contain few genes that help bacteria survive
• Shapes of bacterial cells

  • Bacillus= rod shaped
  • Coccus= spherical
  • Spirillum= corkscrew shaped
• Flagella


  Long, whiplike extensions made of proteins that allow cells to swim (movement)
• Organelles


  Small cell parts; each have their own structure and function
• Compartmentalization


  Makes more efficient cells because processes are divided
• Cell wall


  Structure surrounding plant cells. Used for support/protection
• Centriole

  Tube structure in animal cells. Play role in cell division/reproduction
• Chloroplast


  Double membrane organelle in plant cells. Photosynthesis
• Cilia


  Short flagella surrounding the cell used for movement of cell
• Cytoplasm


  Gel-like substance that fills the cell in which organelles are bathed
• Endoplasmic Reticulum (ER)


  • System of membranes that transport proteins
  • Smooth ER= no ribosome
  • Rough ER= ribosome
• Golgi apparatus


  Membranous sacs that package materials in vesicles for movement around the cell or export out of the cell
• Lysosome


  Special vesicle in animal cell that contain enzymes to break down food
• Mitochondrion


  Major site of ATP synthesis
• Nucleus


  Organelle surrounded by nuclear membrane. Genetic control center
• Chromatin


  • Consists DNA, RNA, and protein
  • Packages DNA in the cell
  • Reinforces DNA molecules to allow mitosis
  • Prevents DNA damage
  • Controls gene expression
  • DNA replication
• Chromosome


  Carries genetic information
• Nuclear envelope


  Has thousands of nuclear pores + allows material in and out of the nucleus
• Nucleolus


  Within nucleus, where RNA is made
• Plasma/cell membrane


  Surrounds all cells, selectively permeable
• Ribosomes


  Small bodies of RNA that catalyze the synthesis of proteins. Found floating in cytoplasm or attached to RER
• Vacuole


  Vesicles in cell that store water and food
• Colonies


  Groups of unicellular organisms living together
• Biofilms

  Bacteria that attach to objects and form colonies. They cooperate to change conditions in the biofilm to fit their needs
• Division of labor


  • Requirement: need to have specialized cell types
  • Ex. Gland cell= makes chemicals
  • Nerve cell= conducts electrical signals
  • Muscle cell= specialized for movement
• Order


  • Cell
  • Tissue
  • Organ
  • System
  • Organism
• Tissue

  Group of cells with same function
• Organ


  Group of tissues working together
• System

  Group of organs working together
• Organism


  Group of systems working together
• Plant transport systems


  • Exchange gasses with atmosphere
  • Take water from roots to leaves
  • Carry food from leaves to other parts of plant
• Animal systems


  • Circulatory system- moves blood through body
  • Urinary system- moves urine out of body
  • Digestive system- move nutrients through body
  • Nervous system- transport