1. Unit B – Section 2.0
Biology

4. Structures and Function of Cell Organelles
Cell Membrane
Selectively Permeable
Keeps contents
Nucleus
Most obvious organelle in any eukaryotic cell
Surrounded by a double membrane
Control Center of Cell
Contains DNA
Surrounds Nucleolus, which produces ribosomes
Cytoplasm
Aka cytosol
Jelly like substance that surrounds and holds other organelles in place
Consists of mostly water, and many proteins responsible for cell metabolism
Vacuoles
Endoplasmic Reticulum
Continuation of the outer nuclear membrane
2 types
Rough ER – has ribosomes on outside – synthesizes proteins
Smooth ER – synthesizes lipids and membrane proteins
Ribosomes
Synthsize Protein
Lysosomes -
Golgi apparatus
Membrane bound structure (single membrane)
Stack of Vesicles that package molecules for transport elsewhere in the cell
Mitochondria
‘Mighty Mouse’ Power House of the Cell
Provides
Chloroplasts
Cell Wall

5. Similarities and Differences between plant and animal cells
Plant Cell
Animal Cell
Cell Wall (composed of cellulose) and Cell Membrane
Cell Membrane only (No Cell Wall)
Chloroplasts producing chlorophyll
No Chloroplasts
Large Vacuole
Small Vacuoles & Vesicles
Undergo Photosynthesis and Cellular Respiration
Only Cellular Respiration
No Centrioles
Centrioles

6. Cell Composition Elements: C, H, O, N Lipids (fats and oils)
Carbohydrates (sugars and starches)
Proteins (muscles fibres and enzymes)
Nucleic Acids (DNA, RNA)

7. Cell Equilibrium
The cell membrane is sometimes referred to as the plasma membrane.
The plasma membrane is made up of a phospholipid bilayer and some proteins
2 layers
Hydrophobic Tails and hydrophilic heads

9. 2.2 – Transport through cell – Particle Theory of Matter
All matter is made up of particles. Different substances will have different size and composition of particles
Particles are constantly moving. Solids least, Gases, most. Change in energy to substance will change movement.
Particles are attracted to each other and may form bonds
Particles have spaces between them (least in solids, most in gases) Exception: Ice.

10. Vocabulary
Selectively Permable – Controls what enters and exits cells (aka semi-permeable)
Diffusion – materials go from high concentration to low concentration. Perfume spreading through a room.
Rate of Diffusion – Can be increased by adding energy and increasing molecular movement

11. More Vocab.
Concentration Gradient – Determines direction of water or solution will move.
Osmosis – water going from high concentration to low across a semi-permeable membrane (selectively permeable).

12. More Vocab!
Dialysis – solutes going from high concentration to low across a semi-permeable membrane.
Facilitated diffusion- molecules transported across the semi-permeable membrane with the use of channel or carrier proteins.
All of the above go with the
concentration gradient (high to low)
All of the above don’t require energy

13. Even more Vocab!
Active transport – carries molecules across the semi-permeable membrane against the concentration gradient (low to high). This requires energy and carrier molecules. The energy that a cell uses is ATP (adenosine triphosphate)

14. Types of Solutions
Solutions that cells are placed in are categorized into 3 types depending on the concentration of solute the solution has to the cell.
Hypertonic
Hypotonic
Isotonic

15. Isotonic – Same Concentration

16. Hypotonic – Less Solute

17. Hypertonic – More Solute

18. Cells can also bring in large objects:
Endocytosis – Cell pinches off small chunks of material
 Exocytosis – Cell dumps out small chunk

19. 2.3 Medical Applications
Liposomes - create an artificial membrane that can house medicines and carry them throughout the cell.
Insulin – (naturally made) glucose controls cells in the pancreas to release insulin by exocytosis. Insulin increases the intake of glucose into cells
Peritoneal dialysis – filtering the blood by diffusion
Desalination – reverse osmosis – force water out of a membrane so that it goes against the osmotic gradient.

20. Cell Size
Why cells are roughly the same size no matter what they do or are located?
Cells are roughly cube like in shape and as the cell grows in size the Surface Area :Volume ratio gets smaller. This is bad for the cell.
Surface area determines how much material can come in and how much can leave. Materials come in via diffusion across the membrane. You want lots of this.
Volume represents how much stuff is needed (food and necessary gases) and how much must be gotten rid of (wastes solids and gases). Materials come in via diffusion across the membrane.
The cell also responds to slowly to its environment if it gets too large

21. Calculating Surface Area to Volume Ratio
Before we calculate the ratio of surface area to volume…we need to review how to calculate Surface Area and volume independently…

22. Calculating Surface Area
You should recall from math:
Surface Area = Sum of the AREAS of each side.
For example:
This rectangle has 6 sides.
Short sides = 3cm each, Long side = 5cm
1. So calculate the area of each side :
Short = 3cm x 3cm = 9cm2
Long = 3cm x 5cm = 15cm2
2. Multiply each by the number of sides:
Short = 2 sides x 9cm2 = 18cm2
Long = 4 sides x 15cm2 = 60cm2
3. Add them together:
18cm2 + 60cm2 = 78cm2

23. Calculating Volume Again…recall from math
Volume = length x width x height
Which for the same rectangle:
5cm x 3cm x 3cm = 45 cm3
**Note –> 1 cm3 = 1 mL

24. Now we can show the ratio of surface area to volume
Back to the same rectangle:
We always show the ratio as:
surface area: volume
SO = cm2 : 45 cm3
Reduced to = 78:45
AND IT MUST BE IN THAT ORDER!!
Your notes show:
This is an example calculation that will only work for cubes that are the same size on each side.

25. Example #1 Calculate the surface area:volume ratio Side length: 1.0 cm
 Area of each side: 1.0 cm x 1.0 cm = 1.0 cm2
Surface Area: 1.0cm2 x 6 sides = 6.0cm2
Volume: 1.0cm x 1.0cm x 1.0cm = 1.0cm3
Answer: 6.: 1

26. Example #2 Surface Area: Volume for a cube: Each side is 2.5 cm
Area: 2.5cm x 2.5cm = 6.25cm2
6 sides x 6.25cm2 = 37.5cm2
Volume: 2.5cm x 2.5cm x 2.5cm = 15.63cm3
Answer = 38 : reduce it = 19: 8

27. Example #3 Surface Area: Volume for a cube: Each side is 4.0 cm
Area: 4.0cm x 4.0cm = 16cm2
6 sides x 16cm2 = 96cm2
Volume: 4.0cm x 4.0cm x 4.0cm = 64cm3
Answer = 96 : reduce it = 3 : 2

28. Homework: Practice problems in Text pg 289 #1-3
Check and Reflect p294 – even #’s
Section 2.0 quiz on Tuesday!!