science: chpt. 18 test Flashcards
Outer protein layer that surrounds the genetic material of a virus
Capsid
Microscopic prokaryotes most are beneficial to humans and to the environmental, but small percentage can cause disease
Bacteria
Dormant bacterial cell able to survive for long periods of time during extreme environmental conditions
Endospore
Process in which NAD+ is regenerated, allowing cells to maintain glycolysis in the absence of oxygen
Fermentation
Organism that cannot make its own food and gets its nutrients and energy requirements by feeding on other organisms; also called a consumer
Heterotroph
Hairlike, submicroscopic structure made of protein that can help a bacterial cell attach to environmental surfaces and act as a bridge between cells
Pili
Protein that can cause infection or disease
Prion
Microscopic, unicellular organism without a nucleus or other membrane-bound organelles
Prokaryote
RNA virus, such as HIV, with reverse transcriptase in its core
Retrovirus
Nonliving strand of genetic material that cannot replicate on its own, has a nucleic acid core, a protein coat, and can invade cells and alter cellular function
Virus
The adding of dyes to identify the types of bacteria
Gram stain
Heterotrophic eubacteria that obtains their energy by decomposing organic molecules associated with dead organisms or organic waste
Saprotrophs
Bacteria that requires the use of oxygen to grow
Aerobes
How is bacteria identified?
Shape, cell wall, and movement. There are three shapes of bacteria, cocci (round), bacilli (rod shaped), spirilli (spiral shaped). They are also identified by their cell walls. Gram stains help identify the two major types of bacteria. Lastly, they are identified by their movement. Some are stationary, some move using flagella, and other move over secreted slime.
How do Bacteria reproduce?
Bacteria reproduce by asexual processes called binary fission. In this process, the cell is divided and the chromosome replicates. Then the cells form a cell wall and become two identical cells. Some bacteria reproduce by conjugation. Conjugation is when two bacteria attach and exchange genetic information.
