Cells BIO HL

Prokaryotes

Eukaryotes

Compartmentalization

non-compartmentalised

lack membrane-bound organelles

advantages of compartmentalization

Specialization of cells

lable the plant cell

Plastids

plasmodesmata

Inter cellular connections that bridge the cytoplasm of two different cells together.

• Facilitates the movement of particles between plant cells eg.  mRNA, proteins etc (large and small molecules)

• Also help during the development of plant cells and in the mature tissue

central vacuole

chloroplasts

cell wall

How to calculate the actual size when suing a microscope

1. 1. Measure the Microscope Field of View (FOV)

2. 2. Calculate the Diameter of the Field of View

3. 3: Measure the Size of the Specimen

4. 4: Calculate the Magnification of the Specimen

5. 5: Calculate the Actual Size

6. EXAMPLE: Let's say the diameter of the FOV is 2000 µm and the observed diameter of a cell is 40 µm. The total magnification is 400x (40x objective and 10x eyepiece).

   1. Ratio = Observed diameter / FOV diameter = 40 µm / 2000 µm = 0.02

   2. Actual size = Ratio / Total magnification = 0.02 / 400 = 0.00005 µm (50 nanometers)

formula for calculating magnification when using a microscope

magnification lense x magnification of the eyepiece

terms for microscopes: magnification, resolution

magnification: ratio of an object’s image size to real size

resolution: ability to distinguish between two objects, minimum for how far apart they need to be.

contrast: visible differences in brightness between parts of the sample

electron microscope

• uses beams of electrons

light microscope

pros and cons of electron microscope

pros and cons of light microscope

types of electron microscope