Microscopy and Cell Types

A type of microscopy that uses a beam of electrons to create an image of the sample. It is used to visualize the internal structures of cells and organisms.

A type of microscopy that uses a beam of electrons to scan the surface of a sample. It is used to visualize the surface topography of cells and organisms.

A type of microscopy that uses fluorescent dyes to label specific molecules in cells. It is used to visualize the location and distribution of molecules within cells.

A type of microscopy that uses differences in refractive index to create contrast between different structures in the sample. It is used to visualize unstained biological samples.

A type of microscopy that uses a single beam of light to illuminate the sample. It is used to visualize stained biological samples.

A type of microscopy that uses a dark background to illuminate only light that is scattered by the sample. It is used to visualize unstained biological samples.

A type of microscopy that uses a beam of polarized light to illuminate the sample. It is used to visualize birefringent materials, such as crystals or fibers.

Phospholipid monolayers are a single layer of phospholipids. They are found in archaea, which have a different cell membrane structure from bacteria and eukaryotes.

Isoprene units are branched hydrocarbons that are found in the side chains of archaeal phospholipids. These give archaeal membranes a different structure from bacterial membranes.

A protein that binds to single-stranded DNA during DNA replication. SSBs keep the DNA strands separated, preventing them from re-annealing.

In DNA replication, the enzyme that joins Okazaki fragments together. It forms phosphodiester bonds between the 3' hydroxyl group of one fragment and the 5' phosphate group of the next fragment.

A protein that binds to the origin of replication (oriC) in bacteria and initiates DNA replication. It causes the unwinding of DNA at the oriC site.

An enzyme that unwinds the double helix of DNA during DNA replication, breaking the hydrogen bonds between the nitrogenous bases.

The process by which nitrogen gas (N2) is converted into ammonia (NH3) by certain microorganisms. This process is essential for life on Earth as it provides the nitrogen that plants and other organisms need to grow.

The enzyme that catalyzes nitrogen fixation. It is found in certain bacteria and archaea that are able to convert nitrogen gas into ammonia.

The process by which ammonia is converted into nitrate by certain microorganisms. This process is essential for the cycling of nitrogen in the environment.

The process by which nitrate is converted into nitrogen gas by certain microorganisms. This process is essential for the cycling of nitrogen in the environment.

A type of operon that is controlled by the presence or absence of a particular molecule. The trp operon is an example of a repressible operon, where the synthesis of tryptophan is repressed when tryptophan is present.

A type of operon that is controlled by the presence or absence of a particular molecule. The lac operon is an example of an inducible operon, where the synthesis of enzymes that break down lactose are induced when lactose is present.

The process by which genetic information is transferred from one bacterium to another through direct contact. This typically involves the transfer of a plasmid, a small circular piece of DNA that can replicate independently of the bacterial chromosome.

The process by which a bacterium takes up naked DNA from its environment. This DNA can be integrated into the bacterial chromosome or can exist as a separate plasmid.

The process by which a virus transfers genetic material from one bacterium to another. This can occur when a virus carries a piece of bacterial DNA from one bacterium to another.

The process by which a virus transfers its own genetic material into a host cell. This can lead to the lysis of the host cell or to lysogeny, where the viral DNA is integrated into the host cell's genome.

A method of DNA amplification that uses a series of cycles of heating and cooling to create millions of copies of a specific DNA segment from a small sample of DNA.

A technique that uses DNA sequencing to identify different species of bacteria in a sample. It targets the 16S ribosomal RNA gene, which is highly conserved in bacteria but contains hypervariable regions that can be used to differentiate between closely related species.

A type of symbiotic relationship in which both species benefit from the interaction. For example, the relationship between nitrogen-fixing bacteria, which convert nitrogen gas into a usable form, and plants, which provide the bacteria with a source of energy.

A type of symbiotic relationship in which one species benefits from the interaction while the other species is neither benefited nor harmed. For example, the relationship between certain bacteria that live on our skin and us, where the bacteria benefit from a place to live and we are not affected.

A type of symbiotic relationship in which one species benefits from the interaction while the other species is harmed. For example, the relationship between a parasite and its host, where the parasite benefits from the host but the host suffers.

A type of symbiotic relationship in which one species kills and eats the other species. For example, the relationship between a predator and its prey, where the predator benefits from the prey but the prey suffers.

A type of bacteria that is closely related to mitochondria, which are organelles found in eukaryotic cells. Mitochondria are thought to have evolved from ancient bacteria that were engulfed by a eukaryotic cell.

The process by which light energy is converted into chemical energy in the form of glucose. This process occurs in plants, algae, and some bacteria. It requires the inputs of carbon dioxide and water and produces glucose and oxygen.

The second stage of photosynthesis, which occurs in the stroma of chloroplasts. It uses the chemical energy produced in the light reactions to convert carbon dioxide into glucose. The Calvin cycle is also known as the dark reactions, as it does not require light directly.

A molecule that is found in fungal cell walls, giving them their characteristic rigidity. It is a type of sterol and is not found in bacterial or plant cell walls.

An enzyme that is involved in the synthesis of beta-1,3 glucan, a major component of the fungal cell wall.

A type of carbohydrate that is found in fungal cell walls. It is also a major component of plant cell walls.

A type of protein that is found in fungal cell walls. They are important for cell wall integrity and for the interaction between the fungus and its environment.

A type of microscope that uses fluorescent dyes to label specific molecules in cells. It is used to visualize the location and distribution of molecules within cells.

A compound that inhibits the activity of DNA gyrase, an enzyme essential for bacterial DNA replication and repair. This leads to breaks in bacterial chromosomal DNA and activates the bacterial SOS response, a mechanism for repairing damaged DNA.

A type of antibiotic that inhibits the synthesis of bacterial cell walls. This interferes with the bacterial cell's ability to divide and grow.

A type of antibiotic that inhibits the synthesis of proteins in bacteria. This interferes with the bacterial cell's ability to produce essential proteins.

Proteinaceous filaments that project from the surface of some archaeal cells. They allow archaeal cells to adhere to different surfaces. These adhere to surfaces in the environment and enhance the formation of biofilms.

The sugar found in pseudomurein. This is a peptidoglycan-like molecule that makes up the cell walls of certain archaea, but is structurally distinct from peptidoglycan and has a unique sugar moiety.

A type of bacterial growth curve that has four phases: lag, log, stationary, and death. During the lag phase, bacteria are adapting to their new environment and are not dividing rapidly. During the log phase, bacteria are dividing at an exponential rate. During the stationary phase, bacterial growth slows down as resources become limited. During the death phase, bacteria begin to die off due to a lack of resources or due to the accumulation of toxic waste products.

Two subunits of the bacterial ribosome: 30S and 50S. The 30S subunit is responsible for binding to mRNA, while the 50S subunit is responsible for catalyzing peptide bond formation during translation.

A type of bacteria that produces lactic acid as a byproduct of fermentation. They are important in the production of fermented foods such as sauerkraut and kimchi.

The point at which the rate of photosynthesis no longer increases with increasing light intensity. It is a limiting factor in the efficiency of photosynthesis, as the photosynthetic machinery can only process light at a certain rate.

A type of bacterial structure that is a thick, protective layer surrounding some bacterial cells. Capsules can contribute to bacterial virulence, as they can help prevent bacteria from being phagocytized by immune cells.

A type of lipid that is found in the outer membrane of gram-negative bacteria. Endotoxins are released when the bacteria die and can cause a number of symptoms, including fever, inflammation, and shock.

A phage that contains an endolysin, an enzyme that degrades the bacterial cell wall. These phages are used in phage therapy, a potential way to treat bacterial infections.

A fusion inhibitor drug that prevents HIV-1 from entering host cells by binding to the gp41 protein, which is a key component of the HIV envelope.

A glycoprotein found on the surface of HIV-1. It binds to the CD4 receptor on the surface of host cells, which is the first step in HIV entry.

A receptor found on the surface of host cells. HIV-1 gp120 binds to the CD4 receptor, which is the first step in HIV entry.

An enzyme found in retroviruses, including HIV, that is responsible for transcribing viral RNA into DNA. Reverse transcriptase is essential for the replication of retroviruses.

A type of phage that can exist in two different states: the lytic cycle and the lysogenic cycle. In the lytic cycle, the phage replicates and lyses the host cell. In the lysogenic cycle, the phage DNA integrates into the host cell's genome and is replicated along with the host cell's DNA.

A type of phage that replicates inside the bacterial cell and then lyses the cell to release new phages. In the lysogenic cycle, the phage DNA integrates into the host cell's genome and is replicated along with the host cell's DNA.

A type of phage that integrates its DNA into the host cell's genome and is replicated along with the host cell's DNA. The phage DNA can remain integrated in the host cell's genome for many generations without causing any harm to the host cell.