Keywords: Chapter 1 Flashcards
unicellular
an organism consisting of only one cell
multicellular
an organism made up of many cellss
biodiversity
the variety of organisms found in an area or on Earth
capsid
a protein coat surrounding the nucleic material of a virus
acellular
non-cellular
obligate parasite
obligate=forced; a parasitic organism that cannot complete its life-cycle without exploiting a suitable host ( if an obligate parasite cannot obtain a host it will fail to reporduce)
host
an organism that harbours a parasite
pathogenic
an organism that causes disease
bacteriophage
a type of virus that infects bacteria; the word “phage” means “to eat”
nucleoid
an irregularly shaped region within the cell of a prokaryote that contains all or most of the genetic material
prokaryotic
an organism where the nuclear material is not enclosed in a membrane
eukaryotic
any single or multicellular group of organisms that have a membrane-bound nucleus containing genetic material
flagellum
a whip-like, protruding filaments that help cells or micro-organisms move; plural of flagellum is flagella
autotrophic
organisms which can synthesize their own food e.g. green plants, algae and some bacteria
heterotrophic
any organism that sources food from its environment because it cannot make its own food e.g. animals, fungi, most bacteria
saphrotrophic
plant or fungal micro-organisms that feeds on dead or decaying organic tissues of other organisms
binary fission
asexual reproduction of a single cell in which divides by mitosis; the cell regenerates as two or more separate cells having the same chromosomal identities as the parent cell
endospore
a tough, protective, non-reproductive bacteria structure that contains DNA and cytoplasm and lies dormant to survive unfavourable environmental conditions in order that it can germinate once conditions improve
plasmid
a plasmid is a small, circular, double-stranded DNA molecule that is distinct from a cell’s chromosomal DNA
aquatic
living in or around water
phytoplankton
very small plants (algae) that float on or near the surface of water
zooplankton
consisting of small animals and the immature stages of larger animals which floar on or near the surface of the water
sessile
sessile organisms are usually permanently attached to something and can cannot move on their own but can move through outside sources (such as water currents)
chitin
a fibrous substance consisting of polysaccharides which is the major constituent in the exoskeleton of arthropods and the cell walls of fungi
hyphae
A NETWORK OF MULTI-CELLED THREADLIKE FILAMENTS FORMING THE MYCELIUM OF A FUNGUS
mycelium
a vegetative mass or network of fungal hyphae found in and on soil or organic substances
multinucleate
cells that have more than one nucleus per cell i.e. multiple nuclei shared in one common cytoplasm
rhizoids
threadlike structures that anchor lower plants and fungi to a surface
budding
a form of asexual reproduction which involves the pinching off of a offspring from the parent cell; the offspring cell is genetically identical to the parent
decomposers
organisms that break down dead plant and animal (organic) material e.g. bacteria and fungi
saprophytes
organisms that live off dead organic matter
mutualism
a symbiotic relationship where both organisms benefit
commensalim
a symbiotic relationship where one organism benefits without harming or affecting the other organism
parasitism
a symbiotic relationship where parasitic organisms benefit while causing harm to their hosts
lichens
composite organisms made up of fungi that grow symbiotically with algae or cyanobacteria
ruminant
an even-toed mammal that chews the cud of regurgitated from its rumen e.g. cattle, sheep, antelopes, deer, giraffes, and their relatives
mycorrhiza
the symbiotic association of fungi with the roots of trees
pathogen
infectious biological agent or organism that causes disease
vector
an agent who carries and transmits an infectious pathogen into another living organism
host
living cell in which a virus (or foreign molecule or micro-organism) multiplies or hides
epidemic
refers to a sudden increase in the number of cases of a disease above what is normally expected
pandemic
refers to an epidemic that has spread over several countries or continents, usually affecting a large number of people
lymphocyte
white blood cell type which fight infection
antigen
a complex molecule that induces an immune response (or disease reaction) in the body
antibody
a protein made by the immune system to target and combine with a specific antigen (invader) and make it useless
phagocytosis
the process by which a cell engulf a solid particle to form an internal compartment known as phagosome (phago-eat, cyto-cell)
lysosome
an organelle containing digestive enzymes to break down bacterial or viral cell walls
