Taxonomy and Carl Linnaeus

Taxonomy

• Taxonomy is the practice of classifying organisms, derived from the Greek words "taxis" meaning arrangement and "nomos" meaning method.

Carl Linnaeus and His Contribution

• Carl Linnaeus, a Swedish botanist, is considered the "Father of Taxonomy" for his significant contributions to the classification of living things.
• Linnaeus' classification system is still in use today, and his work remains integral to how we name, rank, and classify plants and animals.

Classification System

• Linnaeus used simple physical characteristics of organisms to identify and differentiate between different species.
• His classification system is based on genetics.
• The system involves a hierarchy of groups, with each classifying group (taxon) subdivided into smaller groups to distinguish different levels of similarity.

Levels of Taxonomy

• The taxonomy system consists of eight distinct levels, which will be explored in further detail.

Microscope Basics

• Resolving power is the ability of a microscope to differentiate between two nearby structures as separate, and higher resolution means closer objects can be seen with clearer and more detailed images.
• Magnification is typically increased to 1,000 times when using oil immersion lenses to investigate smaller cells, such as prokaryotic cells.

Light Microscopy

• Light microscopy is used to view specimens because light entering the specimen from below is directed into the observer's eye.
• Samples must be thin or translucent for light to travel through them.
• Magnification can be up to 400 times in light microscopes commonly used in undergraduate colleges.

Dissecting Microscopy

• Dissecting microscopes provide a three-dimensional image of the specimen with a lower magnification (20 to 80 times the object size) compared to light microscopes.
• They allow for the simultaneous examination of multiple components in focus, and are used to examine thick objects.
• Most contemporary dissecting microscopes are binocular, providing a clear, enlarged image of both the anatomy of the entire organism and the tissue structure inside.

Electron Microscopy

• Electron microscopes use an electron beam instead of a light beam, offering higher resolving power and magnification.
• Electron microscopes cannot be used to examine live cells, as the preparation process kills the cells, and the electron beam requires a vacuum.
• Scanning electron microscopes reveal the surface properties of a cell by reflection, while transmission electron microscopes provide details of a cell's internal structures.

Cell Technologists

• Cytotechnologists (cell technologists) are professionals who study cells through microscopic examinations and other laboratory tests.
• They determine whether cellular changes are within normal limits or are abnormal, and consult a pathologist when abnormalities are detected.
• Cytotechnologists play a vital role in saving people's lives by enabling early treatment of abnormalities.

Cell Size and Measurement

• A typical human red blood cell measures 8 micrometres (μm) in diameter.
• Approximately 250 red blood cells can fit on the head of a pin.

Microscope Optics

• The lens mechanism of a light microscope allows the user to see the specimen by allowing visible light to flow through while also deflecting it.
• The way light passes through the lenses creates an inverted image, which is corrected in binoculars and dissecting microscopes to appear upright.

This quiz is about the practice of classifying organisms, including the contributions of Carl Linnaeus, the 'Father of Taxonomy'. Learn about the importance of classification and Linnaeus' impact on the field.