Biology chapter 12 (red)

Carcinogen

Any substance thought to be able to cause cancer

Plasmids

small DNA circles; exchanged among bacteria and very often contain the genes that make bacteria resistant to antibiotics

Prokaryote

genetic material is clumped in a dense region of the cell called the nucleoid; bacteria

Eukaryote

 having cells with membrane-­bound nuclei and membrane-­enclosed organelles

Binary Fission

process where bacteria reproduce rapidly and asexually

Pastur

who created the Germ concept of disease

Koch Postulates

• The suspected pathogen must be identified in each of the diseased animals

• The suspected pathogen must be grown in a pure culture

• Organisms from the culture should cause disease when injected into healthy animals

• The suspected pathogen must be identified in these diseased animals

Virus

a molecule of genetic material (DNA or RNA) enclosed in a geometric protein structure called a capsid

Phagocytes

wbc that roam through your tissues and body cavities, engulfing and disposing of any bacteria, viruses, and cellular debris they encounter

Interferon

chemical messenger which limits the spread of the virus

Tissue fluid

originates in the plasma of the blood; makes things swell and become inflamed

Thymus

An organ that grows smaller the older you get; one of the most inconspicuous lym­phatic organs

Lysozymes

destroys bacteria

Acquired immunity

immunity that results from circulating antibodies or memory cells

Active acquired immunity

developed through an immune response to a pathogen

Passive acquired immunity

develops when some­one receives an infusion of antibodies from someone else

Innate immunity

results from factors other than the presence of antibodies and memory cells

Species immunity

a type of innate immunity that occurs because many pathogens infect only particular types of organisms

Antibiotics

substances produced by bacteria, molds, and certain other organisms that are effective in stopping the growth of microorganisms

Penicillin

powerful antibiotic that is extracted from a yellowish excretion of mold

Alexander fleming

bacteriologist working in London, discovered penicillin by accident in 1928