Lesson Plan #2

Cells and their parts[mb1]

  • Cytoplasm- the jelly like substances in all cells that holds all the organelles,  transports materials throughout the cell and is the place of many chemical reactions
  • Organelles- cell parts that perform various functions

Some vital cell organelles: see page 4

  • Nucleus[mb2] – controls the cells metabolism and is the cell’s control center
  • Vacuoles- are the storage tanks of the cells either holding goods or wastes
  • Ribosome’s- protein producers that sometimes float and sometimes are attached to cell wall
  • Mitochondria[mb3] - the cells “engine” which house special enzymes used to extract energy from nutrients
  • Chloroplasts- the green structures in plants and one cell organism that hold the Chlorophyll which contain green pigments and that capture the light energy from the sun

Cell Membrane (skin)

  • Separates cells from each other
  • Controls what comes in and out of cells. There are two ways molecules move in and out of cells:
  • Diffusion-a naturally occurring process whereby molecules move from higher concentrations to lower by the jiggling of the molecules themselves and do not require energy of the cells. When in the presence of salt from runoff plants may not diffuse enough water into their cells and cause death to the plants.[mb4]
  • Active transport- cells use energy from ATP (high energy molecules) to move molecules from areas of high concentration to low (plants do so to bring water into them)
  • Some times molecules such as starches and proteins are to large and complex to enter the cell and so they need to be broken down into amino acids (by proteins) and simple sugars (by starches). This process is called digestion. They are then reassembled inside the cell to make proteins starches and cell parts. This process is called synthesis.
  • There are some cells that have in their membrane receptor molecules which “talk” with other cells. An example of this is hormones.
  • Do questions 11-25

[mb1] The Poskim many places mention that they don’t discuss things that are not observable and thus they don’t mention cells. Many times though Kabbala does make mention of amazing things only discovered today by science.

[mb2]A modern shaila  has arisen in regards to taking out a nucleus of certain cells and replacing them with the nucleus of someone else’s-this process is called cloning. Is cloning mutar?

[mb3]An interesting tool has been developed by scientists in tracing a genetic pool by looking at the mitochondria-which is the only organelle which contains a single copy of DNA of its own and is passed down from mother to daughter only. Thus geneticists can scan the mitochondrial DNA and see which women are related (See lesson 19 how). They have found that 40% of Ashkenazi woman come from only four mothers!

[mb4]The pasuk in shoftim 9:45 says that salt inhibits the growth of plants