Unit 1: B01, B02, B5.1 Key Notes

All known living organisms are made of cells. Levels of organization exist in multicellular organisms. Tissues are a group of cells that all perform the same function.

Intro to Microscopes Parts of a microscope and safe handling procedures.

Cells Lab Wrap Up What type of cells are these? – Which structures can you identify?

Cells Lab Wrap Up What type of cells are these? – Which structures can you identify?

Calculating Magnification Size in the picture = Actual size (real life) X magnification 2000 mm = 20mm x 100x This equation can be re-arranged to solve for any of the components. X =

Thinking Question Are all animal cells the same? Do all plant cells have the same function? Write down your thoughts and give an example to illustrate.

Specialized Cells Different types of cells perform different functions. The structure of the cell is related to its function!

Cells Perform Specific Functions Read pg. 24 As you read about the six types of specialized cells, write down this information about the red blood cell: – a description of the cell type – The function of the cell – How the cell performs its specific function

An example you can SMELL An example you can SEE Equilibrium: when the concentration of the solute is the same throughout a system. Diffusion

Concentration

The net movement of molecules from a region of their higher concentration to a region of their lower concentration down a concentration gradient, as a result of their random movement. Diffusion

Partially permeable membranes = semipermeable membranes – Only some molecules can pass through the membrane via diffusion. Cell membranes are semipermeable Selectively Permeable Membranes

Cell Membranes

The diffusion of water molecules from a region of their higher concentration (dilute solution) to a region of their lower concentration (concentration solution) through a partially permeable membrane. Osmosis

mations/osmosis/Osmosis.swf mations/osmosis/Osmosis.swf Osmosis

Osmosis Lab Answer the questions at the end of your chicken egg osmosis lab. Look at your lab observations and data: – What happens when a cell is exposed to pure water for a long time? Which way did the water move? Why? – What happens when a cell is exposed to a concentrated sugar solution? Which way did the water move? Why?

Osmosis in Blood Cells

Actual Red Blood Cell Pictures Regular cell at equilibrium Solution with more pure water (dilute solution) Solution with more concetrated solutes

*Remember – water is always the particle that moves What about cells with cell walls? – They won’t burst, but they may injure their cell walls. Effect of Osmosis on Cells H2OH2OH2OH2OH2OH2OH2OH2O

Osmosis and Plant Cells

Practice Question

Thinking Question How do plants use the process of osmosis to obtain the water they need for life?

Life processes use diffusion Check out the picture on pg. 29 that shows all the different ways diffusion is used in living organisms. Draw a similar diagram in your book – you can use your own examples!

The Pathway of Water Across a Root

Vascular Bundles Cross Section of a Root:

Cross Section of a Stem

Dicot Leaf

Section of a Leaf

Read your textbook p & take notes on Xylem & Phloem. – What do each of the tubes carry? Both of these tissues are arranged in vascular bundles found in the roots, stem and veins of a leaf.

Water Flow The pathway taken by water through a plant: Root hair  Root cortex cells  xylem  mesophyll cells

Water Flow Water is being pulled upwards because it is either used up in photosynthesis or evaporated off the leaves. This creates a “pull” from above. A water potential gradient is created in the xylem of the stem. This draws cohesive (sticking-together) water molecules up the plant.

Transpiration

Transpiration: Evaporation of water at the surfaces of mesophyll cells followed by loss of water vapour from plant leaves, through the stomata. piration.swf piration.swf

Experiment: To demonstrate transpiration

Potometers: Experiment: Measuring the rate of water uptake

Transpiration What sort of factors do you think would affect transpiration?

Translocation Translocation: The movement of sucrose and amino acids in phloem from regions of production to regions of storage or regions of utilization in respiration or growth.