Lab 1: Microscopy, Cytology, and the Cell Cycle

What is cytology?

Cytology is the study of cell structure and function.

What is the basic structural and functional unit of all living organisms?

The cell.

What maximum magnification can be achieved using a compound light microscope?

Up to $1000\times$.

What are the names and magnification powers of the four objective lenses on a compound light microscope?

Scanning ($4\times$), Low power ($10\times$), High dry ($40\times$), and Oil immersion ($100\times$).

How is the total magnification of a compound light microscope calculated?

By multiplying the ocular lens magnification by the objective lens magnification: $\text{Total Magnification} = \text{Ocular Lens Magnification} \times \text{Objective Lens Magnification}$ (for example, $10\times \times 40\times = 400\times$).

Which microscope component diagram is shown here?

The compound light microscope, showing parts such as the ocular lens (eyepiece), binocular eyepiece tube, revolving nosepiece, objective lenses, stage, mechanical stage, illuminator, mechanical stage adjustment knob, coarse adjustment focus knob, fine adjustment focus knob, arm, base, and condenser with iris diaphragm.

What are the functions of the condenser and iris diaphragm on a compound microscope?

The condenser focuses light onto the specimen from below, while the iris diaphragm controls the amount of light entering the condenser.

When should the coarse adjustment knob be used during focusing?

It should be used for initial focusing only when using the scanning objective ($4\times$).

What does the term 'parfocal' mean in microscopy?

It means objectives are designed so that the specimen stays nearly in focus when switching from one lens to another.

How do field of view and image brightness change as magnification increases?

The field of view decreases and the image gets darker.

What formula is used to calculate field of view ($\text{FOV}_2$) when switching objectives?

$$\text{FOV}_2 = \left(\frac{\text{Objective}_1}{\text{Objective}_2}\right) \times \text{FOV}_1$$

What is resolution in microscopy?

Resolution is the ability to distinguish two close points as separate.

How is the plasma membrane structured according to the fluid mosaic model?

It is composed of a selectively permeable phospholipid bilayer with hydrophilic heads facing outward and hydrophobic tails facing inward, within which proteins float.

Which cellular membrane structure is depicted in this