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
=
X
•
2000 mm
=
20mm
x 100x
• This equation can be re-arranged to solve for any of the
components.
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
Diffusion
• An example you can
SMELL
• An example you can SEE
• Equilibrium: when the
concentration of the
solute is the same
throughout a system.
Concentration
Diffusion
• 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.
Selectively Permeable Membranes
• Partially permeable membranes =
semipermeable membranes
– Only some molecules can pass through the
membrane via diffusion.
• Cell membranes are semipermeable
Cell Membranes
Osmosis
• 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
• http://www.hartnell.edu/tutorials/biology/ani
mations/osmosis/Osmosis.swf
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
Effect of Osmosis on Cells
• *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.
H2O
H2O
H2O
H2O
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. 90 - 91 & 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.
• http://www.biologymad.com/resources/trans
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.