Epithelial Cells of the Small Intestine (as seen with an LIGHT/OPTICAL microscope) Cell Membrane (or plasma membrane) Nucleus Cytoplasm
microvilli
Add this note to your diag: Microvilli on a Small Intestine Epithelial Cell are only shown using an Electron Microscope. Microvilli are finger-like projections of the epithelial cell that increase its surface area to allow more efficient absorption of food molecules.
Cell Ultrastructure
Cell Organelles
Nucleus Contains DNA and RNA. Largest organelle. Bound by a double membrane with nuclear pores. DNA is arranged in chromosomes with genes responsible for control of cell division and protein synthesis. Pores allow mRNA to leave nucleus.
Nucleus
Cell Membrane Fluid mosaic structure. Consists of a phospholipid bilayer interspersed with proteins. Main function is to control the passage of substances into and out of cell.
Cell Membrane See also fig 1 on textbook p53
Cytoplasm The term cytoplasm refers to everything between the cell membrane and the nuclear envelope (nuclear membrane). Cytoplasm consists primarily of water. It also contains various organelles as well as salts, dissolved gasses and nutrients. Many reactions occur here including aspects of Photosynthesis and Respiration.
Cytoplasm
Site of Aerobic Respiration. Provides the cell with ATP. Mitochondria Organelle with a double membrane. Surrounded by a ‘sausage shaped’ outer membrane. The inner membrane is highly folded into cristae. Site of Aerobic Respiration. Provides the cell with ATP.
Mitochondria
Mitochondria The site of aerobic respiration, responsible for producing most of ATP in a cell Bound by a double membrane Inner membrane highly folded to form cristae.
Rough Endoplasmic Reticulum RER = Series of thin intricate hollow channels (or tubes). Folds of membrane which are continuous with the nuclear membrane. Has a large surface area for attachment of ribosomes. Function = Collection and transport of proteins throughout the cell.
Rough Endoplasmic Reticulum
Ribosomes Very small organelles, about 20nm in diameter. Some are found free in the cytoplasm and others are bound onto Rough Endoplasmic Reticulum (RER). Function of ribosomes = Synthesize proteins (assemble proteins from amino acids).
Ribosomes
Smooth Endoplasmic Reticulum SER. Series of thin intricate hollow channels. Folds of membrane which are continuous with the nuclear membrane. Synthesize Lipids and Steroids.
Smooth Endoplasmic Reticulum
Golgi Body Golgi Body (or Golgi Apparatus). Network of flattened membrane bound sacs. (can look like a pile of mini saucers inside a cell!) Receives protein from the Rough Endoplasmic Reticulum (RER) and prepares/modifies them for secretion by the cell. (e.g. Glycoproteins like mucus e.g. Enzymes).
Golgi Body
Golgi Body How Golgi body works Stack of membrane-bound, flattened sacs in the cytoplasm. Sacs are fluid-filled and can pinch off to form vesicles.
Lysosomes Spherical, membrane bound Contain enzymes How Lysosomes Work Spherical, membrane bound Contain enzymes Digest harmful material and worn out cell parts. Can release enzymes outside the cell (exocytosis)
Microvilli Tiny finger-like projections on membranes of certain cells. Increase surface area for absorption Collectively form a brush border
Animal Cell Ultrastructure as Seen with an Electron Microscope Lysosome Smooth Endoplasmic Reticulum Mitochondrion Rough Endoplasmic Reticulum (RER) Cytoplasm Nucleus Ribosomes Nuclear Membrane Nucleolus Cell Membrane Vesicle forming Golgi Body /Apparatus centriole Vesicle
Animal Cell Ultrastructure as Seen with an Electron Microscope Lysosome Smooth Endoplasmic Reticulum Mitochondrion Rough Endoplasmic Reticulum (RER) Cytoplasm Nucleus Ribosomes Nuclear Membrane Nucleolus Cell Membrane Vesicle forming Golgi Body /Apparatus centriole Vesicle
Independent work Finish Cell labels and notes on HB p6 Do the Quiz HB p7 Read p43-49 textbook & answer Q1,3,4 from peach box on p49. Mark magnification calcs (MS will be sent on e-mail this week) REVISE ALL AS BIOL WORK SO FAR FOR IMPORTANT TEST 2ND DOUBLE LESSON NEXT WEEK.