Microbio exam 4 Vocab

penar, i hate this class

Symbiosis

The living together or close association of two dissimilar organisms

Obligatory

interaction or condition required for bacterial growth

Symbiont

Any organism that has a specific relationship with another organism

Mutualism

type of symbiosis where both organisms gain from the association and are dependent on each other

cooperation

beneficial interaction b/w two organisms, NOT obligatory

antagonism

symbiotic relationship where one partner negatively affects the other

syntrophy

growth of one organism either depends on, or is improved by growth factors or nutrients by another organism

endosymbiont

Symbiosis where one organism is found in another organism

bacteriocytes

specialized eukaryotic cell that contains symbiotic bacteria

ectosymbiont

organism grows on the surface of its host

coevolution

evolution of two interacting organisms that benefits their survival with one another

predation

where one organism hunts, kills, and consumes another organism

parasitism

symbiotic relationship where an organism lives on or within another and benefits while the host suffers

competition

interaction between two organisms attempting to use the same source

grazing

grazer feeds on low-growing plants without killing entire organism

epibiotic predators

microbes that attach to the surface of a prey cell, killing and feeding on its contents from the outside

endobiotic predators

microbes that invade, live within, and consume the cytoplasm or periplasm of their prey

parasite

organism that lives within another organism (host) and benefits while the host suffers.

genomic reduction

decrease of genomic information that occurs over time as an organism becomes more dependent on another organism

contact independent growth inhibition

via antibiotics

contact dependent growth inhibition

physical proximity required for toxin delivery

pathogens

any organism that causes disease

immune system

composed of widely distributed proteins, cells, tissues, and organs; Neutralizes or destroy foreign substances

immunity

overall ability of host to resist a infection or disease

immunology

study of host’s defenses against foreign materials

innate immunity

first line of defense against any microbe or foreign material; general mechanisms like skin, mucus, and antimicrobial chemicals

adaptive immune response

activated by cells and chemicals of innate immune sys., targeted to specific foreign agent; has a “memory“

peristalsis

normal shedding of columnar epithelial cells

lysozome

hydrolyzes bond of bacterial cell wall

opsonization

process by which complement and antibody attach to micobes or foreign particles; surface of a microbe is coated with opsonin

opsonins

proteins that coat; 2 kinds: complement protein C3b and Antibodies

opsonized

easily recognized and destroyed by phagocytic cells

membrane attack complex

cytokine

proteins released by immune cells; mediate activity of other cells

chemokines

stimulate cell migration

interleukins

produced by one leukocyte, act on another

colony stimulating forces

stimulate growth and differentiation of immature leukocytes in bone marrow

leukocytes

white blood cells in the immune system

bone marrow

B cell maturation site

hematopoiesis

process by which blood cells develop into specific lineages from stem cells; how red and white blood cells are developed

neutrophils

kill phagocytosed microbes with hydrolytic enzymes and reactive oxygen; highly phagocytic; nuclei has 3-5 lobes connected by chromatin

macrophages

sound the chemical alarm when microbe invades (sentinel cell); larger than monocytes

dendritic cells

detect and phagocytose pathogens; display foreign antigens on their surfaces to share info with lymphocytes to stimulate adaptive immune response

professional phagocytes

specialized WBCs that possess specifc surface recpetors to identify, engulf, and destroy pathogens; Ex: macrophages, neutrophils, dendritic cells, etc.

natural killer cells

large, granular cells detect and destroy stressed, malignant, or virally infected cells

perforins

pore forming protein

granzymes

enzymes that trigger the target cell to undergo phagocytosis

spleen

secondary lymphoid organ; filters blood and traps bloodborne particles for assessment by phagocytes and B cells

lymph nodes

secondary lymphoid organ; capture phagocytosed antigens and present to T cells

langerhans cell

dendritic cell that phagocytoses microbes that penetrate the skin

phagocytosis

where phagocytes englulf foreign particles, large particles, cell debris. Primary immune defense against pathogens

MAMPs

microbe associated molecular patterns; specific regions within common microbial macro molecules that alert host about presence of microbe

PRRs

recognize and bind unique PAMPs viruses, bacteria, or fungi; TLR are a class of this

TLR

transmembrane receptors in macrophages and DCs; recognize and bind MAMPs

antigen presenting cells

cells that take in protein antigens, process them, and present peptide fragments bound to MHC molecules to T cells

inflammation

response of host tissues to damage or infection; recruit components of the immune system

selectins

cell adhesion molecules on activated endothelial cells that line blood vessels

integrins

adhesion receptors on neutrophils activated by selectins

chemotaxis

cehmotactic factors at infection site

T lymphocytes

directly kill infected cells; defend host from foreign material; adaptive

B lymphocytes

produces antibodies to neutralize pathogens; defend host from foreign material; adaptive

antibody mediated immunity

B cells produce antibodies that circulate in body fluids to neutralize extracellular pathogens

cell mediated immunity

based on action of CTL and T helper cells; eliminates intracellular pathogens without using antibodies

antigen

substance that lymphocytes respond to

epitopes

regions of antigen to which a specific antibody binds

haptens

cannot induce immune response alone, BUT become immunogenic when bound to carrier proteins

MHC

collection of genes encoding proteins that enable the host to distinguish between self and nonself

MHC class 2

on cells that can process and present antigens to T lymphocytes; alpha and beta protein chains form transmembrane and antigen binding pocket that bind only non-self peptide fragments

MHC class 1

on all human cells with a nucleus; alpha and beta protein chains form pocket projecting from cell surface can bind to self or non-self antigens

TCR

2 parts: heterodimeric polypeptide receptor and 6 accessory polypeptides; form transmembrane receptor; each pocket has unique sequence specific to an antigen

negative selection

deletion of self-reactive T or B cells during development

T helper cells

promote CTL activity toward target cells

CD4+ T cells

cytokines from DCs direct these cells to mature; T-Helper cells

TH1 cells

TH2 cells

regulatory t cells

CD8+ T cells

destroy unhealthy host cells through a tightly regulated process

CTL

attack target cells infected with intracellular pathogens

plasma cells

antibody

immunoglobin; glycoprotein made by activated B cells; 5 classes; C region and V regions

immunoglobin

many classes; an antigen

crystallizable fragment

stalk of Y shape of antibody; binds receptors on various immune cells; initiates the complement system

antigen binding fragment

top of Y shape in antibody; composed of both constant and variable regions; noncovalent bonds formed b/w amino acids of binding site and epitope

neutralization

antibodies block adherence factors, preventing their attachment to host cells; caused by antibody binding to biologically active materials

viral neutralization

antibody binds virus and blocks binding to host

precipitation

agglutination reaction

occurs when cells or particles are cross linked; immune complex more rapidly pahgocytosed than free antigens

allergy