Immunofluorescence & Microscopy Lecture Review

Flashcards covering key vocabulary from the 'Immunofluorescence & Microscopy' lecture, including cell theory, modern cell biology strands, cell dimensions, and various microscopy techniques.

Cell Theory

Proposed by Schwann (1839) that all organisms consist of one or more cells, and the cell is the basic unit of structure for all organisms. Virchow concluded that all cells arise only from pre-existing cells. Summary: a cell is not only the basic unit of structure, but it is also the basic unit of reproduction.

Three historical strands of modern cell biology

Cytology, Biochemistry, and Genetics are woven together to create modern cell biology.

Cytology

A historical strand of modern cell biology that centers around cellular structure and optical techniques, improved by advancements in microscopes.

Biochemistry

A historical strand of modern cell biology that explores chemical processes through living things, focusing on cellular structure, function, discovery of enzymes, interaction of biological molecules (lipids, proteins, carbohydrates, nucleic acids), and metabolic pathways.

Genetics

A historical strand of modern cell biology that emphasizes information DNA and RNA, including the Watson and Crick DNA model, the genetic code, recombinant DNA technology, and DNA sequencing.

Organelle

Structures within a cell that have specific functions.

Micrometer (μm)

The best unit for measuring the size of cells and organelles, equal to one-millionth of a meter (10^−6 m).

Micron

An historical term for a micrometer (μm).

Microscopy

A technique that allows scientists to visualize cells and cellular movements at very small dimensions.

Light Microscopy

One of the two major forms of microscopy, identified as an earliest tool of cytologists, allowing identification of organelles within a cell.

Electron Microscopy

One of the two major forms of microscopy, used when higher resolution is required.

Brightfield Microscope

The earliest and most basic tool of cytologists, which passes white light through a specimen.

Limitations of Brightfield Microscope

Requires the subject to be chemically fixed, dehydrated, embedded in paraffin or plastic, and stained, meaning specimens are no longer alive and features could be distorted.

Specialized Light Microscopes

Developed to overcome limitations of brightfield microscopy and look at living cells, including phase-contrast, differential interference contrast, fluorescence, and confocal microscopy.

Phase-contrast microscopy

A specialized light microscopy technique that makes it possible to see living cells clearly by utilizing the phase of the light.

Phase of the Light

Refers to the precise positions of crests and troughs as light waves travel, which is utilized in phase-contrast microscopy.

Differential Interference Contrast (DIC) Microscopy

A specialized light microscopy technique that uses polarized light to create high-contrast images of transparent samples.

Fluorescence Microscopy

A specialized light microscopy technique enabling researchers to detect specific proteins, DNA sequences, or other molecules made fluorescent by coupling them to a fluorescent dye or protein, or by binding them to a fluorescently labeled antibody.

Fluorescent Dye

A molecule that emits light of a particular color, used in fluorescence microscopy to label specific cellular components.

Confocal Microscopy

An optical imaging technique that uses a laser to create high-resolution, high-contrast images of biological samples, revealing the thin structure of a specimen by using light from a single optical section on the focal plane.

Immunofluorescence

A key technique where a fluorescent molecule is attached to an antibody, which recognizes and binds to one specific complementary target molecule (antigen). This allows researchers to identify and locate specific target molecules within a cell using a fluorescence or confocal microscope.

Antibody

A protein used in immunofluorescence that recognizes and binds to a specific target molecule (antigen), to which a fluorescent molecule can be attached for imaging.

Antigen

The specific complementary target molecule within a cell that an antibody recognizes and binds to in immunofluorescence.