cells

• Eukaryotic cell


  Cell which has a nucleus and other structures surrounded by membranes
• Cell membrane


  Selectively permeable membrane surrounding the cell and controlling the entry and exit of materials
• Animal/plant cell

  • Made up of eukaryotic cells
  • Cells have a nucleus and other membrane-bound structures
• Cytoplasm


  Jelly-like material that contains dissolved nutrients and salts, and structures called organelles. Where many chemical reactions happen.
• Nucleus


  Contains genetic material, including DNA, which controls the cell's activities
• Cell membrane


  Permeable to some substances but not others, controls movement of substances in and out of the cell
• Mitochondria


  Organelles that contain enzymes for respiration, where most energy is released in respiration
• Ribosomes


  Tiny structures where protein synthesis occurs
• Most cells are specialised and adapted for their function
• Animals and plants consist of many different types of cells working together
• labelled animal cell

  
• Eukaryotic cell


  Cell which has a nucleus and other structures surrounded by membranes
• Cell membrane


  Selectively permeable membrane surrounding the cell and controlling the entry and exit of materials
• Animal and plant cells

  • Have the nucleus, cell membrane, mitochondria, and ribosomes
• Plant cells


  • Also have chloroplasts, cell walls, and permanent vacuoles
• Chloroplast


  Organelle that contains chlorophyll and is where photosynthesis occurs
• Cell wall


  Provides structure and protection, made of cellulose in plant cells
• Vacuole


  A space within the cytoplasm of plant cells that contains cell sap, helps keep the cell swollen
• Animal cells may also have vacuoles, but these are small and temporary
• plant cell labelled

  
• Prokaryotic


  Description of a cell which does not have a nucleus - the DNA is free in the cytoplasm
• Cell membrane


  A selectively permeable membrane surrounding the cell and controlling the entry and exit of materials
• Cytoplasm


  The living substance inside a cell (not including the nucleus)
• Bacterial cells


  • They are all single-celled
  • They are all prokaryotic
• Components of a bacterial cell

  • Chromosomal DNA
  • Plasmid DNA
  • Flagella
  • Cell wall
• Chromosomal DNA


  The DNA of bacterial cells is found loose in the cytoplasm. It is called chromosomal DNA and is not contained within a nucleus
• Plasmid DNA


  Bacteria also have small, closed-circles of DNA called plasmids present in their cytoplasm. Unlike the chromosomal DNA, plasmid DNA can move from one bacterium to another giving variation
• Flagella


  Bacteria can have one or more flagella (singular: flagellum). These can rotate or move in a whip-like motion to move the bacterium
• Cell wall


  Plant and bacterial cell walls provide structure and protection. Only plant cell walls are made from cellulose
• Bacteria are amongst the simplest of organisms. Their cells do not divide by mitosis. Instead they copy themselves by binary fission</b>
• Eukaryotic


  Description of a cell which has a nucleus. Eukaryotic cells also have other structures in the cytoplasm which have membranes around them
• Differences between eukaryotic and prokaryotic cells

  • Size
  • Outer layers of cell
  • Cell contents
  • Genetic material
  • Type of cell division
• Most eukaryotic cells are 5 μm – 100 μm in size, while most prokaryotic cells are 0.2 μm – 2.0 μm in size
• Eukaryotic cells have a cell membrane and are surrounded by a cell wall in plants and fungi, while prokaryotic cells have a cell membrane and are surrounded by a cell wall
• Eukaryotic cells have cytoplasm with cell organelles like mitochondria and chloroplasts, while prokaryotic cells have cytoplasm with ribosomes but no mitochondria or chloroplasts
• Eukaryotic cells have DNA in a nucleus, while prokaryotic cells have DNA free in the cytoplasm and may also have plasmids
• Eukaryotic cells divide by mitosis, while prokaryotic cells divide by binary fission