NAT

• Cell theory

  • The cell is the basic unit of life
  • All organisms are made up of cells
  • Cells came from pre-existing cells
• Types of cells

  • Nerve cell
  • Bacterium
  • Muscle cell
  • Plant cell
  • Red blood cell
  • Egg cell
• Multicellular organism

  Most organisms you are familiar with
• Nerve cell

  • A long cell that can carry messages from your spine to your toes
  • The longest cells are very thin nerve cells of large animals
• Bacterium

  • The smallest cell, about 8000 of the smallest bacteria could fit inside one of your red blood cells
• Muscle cell

  • Long, slender cells grouped together from long, slender muscle tissues
  • The contraction and relaxation of muscle tissue is responsible for movement
• Parts of the cell

  • Plasma membrane
  • Cytoplasm
  • Nucleus
  • Chromosomes
  • Nucleolus
  • Ribosomes
  • Endoplasmic reticulum
  • Golgi apparatus
  • Mitochondria
  • Lysosomes
  • Cytoskeleton
• Types of cells

  • Animal cell
  • Plant cell
• Plasma membrane/cell membrane

  Regulates the movement of water, nutrients and wastes into and out of the cell
• Cytoplasm

  A semi-fluid substance made primarily of water and organic compounds, with various structures (organelles) suspended in it
• Nucleus

  Found at the center of the cell, contains the cell's DNA

  
• Nucleus

  • The chromosome keeper, often called the control center of the cell, surrounded by a double membrane called nuclear envelope
• Chromosomes

  Distinct structures that carry the cell's genetic information
• All organisms have a definite number of chromosomes
• Nucleolus

  Found inside the nucleus, where ribosomes are formed
• Ribosomes

  Organelles that participate in protein synthesis, protein assemblers
• Mitochondria

  Often referred to as the power plants of the cell
• Lysosomes

  Organelles that contain enzymes that aid in the digestion of nutrient molecules and other materials
• Endoplasmic reticulum

  • Rough ER is the site of protein synthesis, manufactures new cell membranes
  • Smooth ER makes lipids, processes carbohydrates, modifies chemicals that are toxic to the cells
• Golgi complex

  Modifies, sorts, and packages proteins and other materials from the endoplasmic reticulum for storage in the cell or secretion outside the cell
• Cytoskeleton

  A network of protein filaments placed in the cytoplasm that allows cells to change shape, move organelles, and move from place to place
• Cytoskeleton

  • The two most important protein filaments are actin filaments (responsible for contraction) and microtubules (for structural strength)
• Cilia

  Slender protuberances that project from the cell body and function in locomotion
• Flagella

  Tail-like projections that protrude from the cell body and function in locomotion
• Structures found in plant cells but not animal cells

  • Cell wall
  • Chloroplasts
  • Large vacuoles
• Types of cells

  • Prokaryotic cells
  • Eukaryotic cells
• Prokaryotic cells

  • Cells without a true nucleus, found in the domains Archaebacteria and Eubacteria
• Eukaryotic cells


  • Cells with a true, membrane-bound nucleus containing DNA and other membrane-bound organelles
• Comparison of prokaryotic and eukaryotic cells

  • True membrane-bound nucleus (absent in prokaryotes, present in eukaryotes)
  • Mitochondria (absent in prokaryotes, present in eukaryotes)
  • Chloroplasts (absent in prokaryotes, present in eukaryotes)
  • Plasma membrane with sterols (no in prokaryotes, yes in eukaryotes)
  • Flagella (sub-microscopic in size in prokaryotes, microscopic in size with 20 microtubules in eukaryotes)
  • Endoplasmic reticulum (absent in prokaryotes, present in eukaryotes)
  • Golgi complex (absent in prokaryotes, present in eukaryotes)
  • Ribosomes (present in both)
  • Lysosomes (absent in prokaryotes, present in eukaryotes)
• Plant cell


  • Cell wall (provides rigidity and a porous medium for circulation of water, minerals, and nutrients)
  • Chloroplasts (organelles that conduct photosynthesis)
  • Large vacuole (stores water, minerals, nutrients, and proteins)
• Guard cells

  Specialized plant cells that regulate the opening and closing of stomata