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83 terms

Biology Words

Kingdom equivalent to Domain Arachaea
Chemically unique cell wall and membranes
Unique genetic system.
Genetic system similar to eukaryotes
May have evolved into eukaryotes
Often, but not always extremophiles
Taxonomic category
Contains orders with common characteristics
Kingdom equivalent to Domain Bacteria
Strong exterior cell wall
Unique genetic system
Same Cell membrane lipid as most eukaryotes
No internal compartments
classified by shape, nature of cell wall, metabolism, or how they attain nutrients
Domain with four kingdoms
Organisms made up of eukaryotic cells
Eukaryotic cells have complex internal structures which allow them to become larger than the earliest cells and enabled evolution of multi-cellular life
taxonomic category below order and above genus
Humans belong to family Hominidae
A subgroup within a family.
Made up of species with uniquesly shared traits such that the species are thought to be closely related.
Humans belong to genus Homo
Domain recognizes 3 most basic cell types.
Kingdom encompaasses large groups such as plants, animals, or fungis.
3 domains are divided into 6 kingdoms
Subgroup within a class
Phylum is subgroup within a kingdom
Many exist within each kingdom
Humans belong to phylum chordata
A unique group of organisms united by heridity or interbreeding Humans are species homo sapiens - only living species that walks upright and uses spoken language
the science of describing, naming, and classifying organisms
Chemical that inhibits growth of or kills some microorganisms
A virus that infects bacteria
can be called just phage
complicated structures
for example can be a capsid with tail with tail fibers
has long DNA molecule ; tail fibers act like syringes injecting DNA into bacterial host
Protein coat of virus
contains special proteins that must match host cell's proteins
capsids have variety of shapes
Membrane-like layer that surrounds capdis of SOME viruses
Gives virus overall spherical shape although capsid can have a very different shape
Made of proteins, lipids, glycoproteins (proteins with attached carbohydrate molecules)
Lysogenic Cycle
Viral replication in which a viral genome ie replicated a a provirus without destroying the host cell
Viral DNA becomes part of host cell's DNA (called provirus)
New cells then produced which contain the hprovirus
May or may never leave host's DNA and enter lytic cycle
A "temperate" virus
Lytic Cycle
Viral replication that results in the destruction of ta host cell and the release of many new virus particles
Viral genetic material enters cell but remains separate from host DNA
Use's host organelles, enzymes, raw materials to copy virus's DNA and make viral proteins
DNA and proteins then assembled to create new virus cells
Host cell breaks open and newly made viruses infect other host cells.
Host cell is destroyed
A "virulent" virus
An organism or virus that causes disease; an infectious agent
Koch's postulates used to identify pathogens
Genetic structure that can replicate independently of the main chromosome of the cell
Usually a circular DNA molecule in bacteria (prokaryotes)
Small extra loops of DNA in a bacteria
Substance prepared from killed or weakened pathogens and introduced into a body to produce immunity
Carry surface antigens from pathogen that body recognizes as harmful
Triggers immune response and forms memory cells against pathogen
Pieces of nucleic acids in a protein coat
Not a living cell
Unable to grow and reproduce
Plantlike protist
Obtain energy through photosynthesis
Vary by pigment
Animal-like protist
Single cell protozoa "first animal"
Ingest other organisms for energy
Move (hunt) using extensions of cell called pseudopodia; also use pseudopodia to capture and engulf prey
Live in fresh water, salt water, soil
Some are free-living; some are parasites
Organism that produces its own nutrients from inorganic substances or from the environment rather than from other organisms
Most plants are autotrophs
Photoautotrophs: get energy from sun
Chemoautotrophs: get energy from inorganic sources like sulfur, nitrogen
Contractile Vacuole
In protozoans, an organelle that accumulates water and then releases it periodically to maintain osmotic pressure
Part of unicellular eukaryotes
Some plants and fungi have rigid cell walls which prevent cells from expanding from too much water
an organism that feeds by breaking down organic matter from dead organisms
Includes bacteria and fungi
Organism that obtains organic food molecules by eating other organisms or their byproducts and that cannot synthesize organic compounds from inorganic materials
Most prokaryotes are hetortrophs
Most absorb from dead organisms, but some are parasites or pathogens
Most live in presence of oxygen, some can live without
Mass of fungal and algal cells that grow together in symbiotic relationship and are usually found on rocks or trees
Fungus gets carbohydrates from the other in exchange for providing protective environment and vitamins and minerals to the photosynthetic partner
Protist disease caused by sporozoans of genus Plasmodium
Spread by mosquito
Sporozoite infects the liver
Invades cells and makes millions of parsites, destroying liver cells
Merozite then infects red blood cells and divides into 8-24 merozites that rupture cell
As red blood cells die, anemia ensues
Animal-like protist
some of most complex single-celled organisms
most or all body covered with short, hairlike structures
Move and hunt for food by beating cillia
Found in fresh water and salt water
Have two nuclei - macronucleus controls routine cell functions; nicronucleous functions in sexual process
Reproduce sexually by conjugation - two cells join temporarily and exchange one of their small nuclei with the other
Has contractile vacuole
a species that benefits from a host species
Host species is harmed in the relationoship
Often lives on or in host, which is usually larger
Fungus-like protist
Multinucleate cytoplasm of a slime mold that is surrounded by a membrane and that moves as a mass
Forms spores
Absorbs nutrients from soil, decaying wood, animal dung
Normally exists as single-celled amoebas
When food/water runs out, cells release spores
Eukaryotic organisms that cannot be classified as fungi, plants, or animals
Very diverse kingdom
*Membrane-bound organelles
*Complex cilia and flagella
*Sexual reproduction with gametes
Animal-like protists
Ingest other organisms for energy
Heterotrophic (as are animals)
Most can move
Most reproduce asexually by binary fission
Includes: amoeboid protists, ciliates like paramecium, flagellates, sporozoans
Cytoplasmic extension on amoeboid protist that functions in food ingestion and movement
Rootlike structure that holds fungi in place and absorbs nutrients
Formed by hyphae, threadlike strands
Organism that absorbs nutrients from dead or decaying organisms
Recycle nutrients that would otherwise stay trapped
Enzymes from fungi break down organic and inorganic matter into nutrients which are then absorbed into the fungi through their cell walls
Animal-like protists that form sporelike cells when they reproduce
Lack flagella, cilia, pseudopodia and do not move
All are parasitic and caus disease
Reproduce asexually and sexually
Having a relationship in which two different organisms live in close association with each other, benefitting from each other
both Archaea and eubacteria
no membrane bound organelles
genetic material is DNA - single chromosome in a mass called a nucleoid
sometimes has plasmids
may have ribosomes & many types of enzymes
cell wall may be one or two layers thick
protein-carbohydrate compound that makes up bacteria cell wall
May have a separate membrane that also covers the peptidoglycan layer
cluster of DNA in bacteria cell
small extra loops of DNA sometimes in bacteria
Purple dye added. Thick layer of peptidoglycan absorbs more dye. No membrane.
Thin layer doesn't trap purple dye. Does absorb pink dye. Has a membrane.

More resistant to medicines and host's defenses.
Get energy from sunlight through photosynthesis. Produce oxygen.
Prokaryote. Only organism to get energy from inorganic source. They like sulfer or nitrogen. Can from all there own amino acids and proteins.
How does bacteria help humans?
Environment - makes oxygen, makes nitrogen for plants, decomposes dead organisms, symbiotic relationoships
Industry - pickles, soy sauce, chemicals like acetone, clean up oil spills
Research - provides genetic research & understanding of DNA
How does bacteria cause disease?
1. producing toxins
2. destroying body tissues
How does antibiotic resistance occur?
Antibiotic sensitive strains killed by antibiotics and the resistant bacteria take over.
Why is it hard to find drugs to treat viruses?
Because the virus enters the host's cells and it is hard to find a drug that will kill the virus without affecting the host's cell.
binary fission
Prokaryotes (bacteria) usually reproduce asexually with a single cell dividing into two identical new cells
Genetic recombination
Three ways that prokaryotes can form new genetic combinations (not really reproduction)
Conjugation - two bacteria exchange genetic material
Transformation - bacteria take up DNA fragments from their environment
Transduction - Genetic material, such as a pasmid, is transferred by a virus (often convey antibiotic resistance)
Endospore formation
Method for bacteria to adapt to harsh conditions
Endospore is thick walled structure
Endospore forms inside bacteria - surrounds DNA and small bit of cytoplasm
Can survive boiling, radiation, acid.
Show no signs of life and can be revived to life after 100's of years
How do protists reproduce?
Asexually, producing offspring geneticallly identical to parVinary fissionent
Sexually as a respone to environmental stress.
Binary fission
One type of protist asexual reproduction
Unicellular organism splits in half after replicating its DNA
Sometimes call mitosis, which is technically only division of nucleus
Prokaryotes (bacteria) don't have nuclei so they have binary fission but not mitosis
One type of protist asexual reproduction
Part of parent pinpches off and forms new organism
Can occur in unicelluar and multicelluar organisms
Different from binary fission cuz offspring smaller than parent
One type of protist asexual reproduction
Part of muticellular organism breaks off and starts new organism
Different from budding cuz budding is performed by organism, fragmentation is result of something done to the organism
Sexual reproduction in unicelluar protists
Mature organism = haploid
Haploid divides by binary fission = haploid gametes
Two gametes fuse=diploid zygote then becomes zygospore
Enviromental conditions improve & mieosis occurs
Haploid cells break out of zygospore & grow into mature cells
Sexual reproduction in muticellular protists
Many muticellular protists reproduce both sexually and asexually
Alternation of generations is both sexual and asexual
How are fungi reproduced?
In sexual reproduction,spores produced meisosis
In asexual reproduction, spores produced by mitosis
Sexual reproduction in fungus
hyphae from one fungus fuses with hyphae from fungus of opposite mating type
form reproductive structure like mushroom
inside structure, nuclei from two mating types fuse
New diploid nuclei undergoes meiosis and produces haploid spore that are released
Asexual reproduction in fungus
Simpler than asexua
specialized hyphae produce long stalks
at tips of talks, haploid spores produced by mitosis
Fungi that develop are genetically identica to parent
Yeast and mold
specific stages of the life cycle that are shared by several types of fungi
species of fungi primarily in unicelular state
reproduce asexually by budding
rapidly growing asexually reproducing stage of some types of fungi
Characteristics of fungi
threadlike bodies
cell walls are made of chitin
absorb nutrients from their environment
carbohydrate found in cell walls of fungi and other organisms
how do fungi get nutrients
can't make food or move to capture food
release enzymes that break down organic and inorganic materials and absorb nutrients
how do bacteria get nutrients
autotrophs or heterotrophs
how do protists get nutrients
how do protists get nutrients
plant-like: photosynthesis
animal-like: heterotrophic (ingest other organism)
fungus-like: absorb nutrients from decomposing wood, etc.
how do bacteria reproduce
archaebacteria - genetic recombination
eubacteria - binary fission or endospore formation
how do protista reproduce
plant-like: usually asexualy, create spores
animal-like: usually asexually, binary fission
fungus-like: create spores
characterists of protista
plant-like: may have flagella ( algaes)
animal-like: unicellular(ciliates, flagellates)
fungus-like: multi-celled or single celled (saprolegna)
animal like protists
amoeboid protists
Four phylum of fungi
plantlike protists
red, green, brown agae
fungus like protists
sllime molds
water molds
downy mildews
rootlike structure that holds fungi in place and absorbs nutrients
organism that absorbs nutrients from dead or decaying organisms
groups of fungi
chytrid - group of aquatic fungi
zygote - sexual reproductive structures that produced zygotes inside tough capsule
sac fungi- have ascus, saclike sexua reproductive structure that produces spores
club fungi - have a basidium, a clublike sexua reproductive structure that produces spores
fungus provides structure
algae or cyanobacterium provides food