Chapter 27-28 Flashcards
Order of Life
Domain to kingdom to phylum to class to order to family to genus to species
what kind of bonds do eukarya have?
Ester Bonds
Which domain has rRNA loops?
Bacteria
what are monophyletic groups?
A group of organisms that consists of a common ancestor and all of its descendants
what are paraphyletic groups?
Includes the most recent common ancestor of the group, but not all its descendants
what does an archaea’s cell wall contain?
a surface layer of proteins
what kind of lipids do archaea have?
isoprene chains
what is a functional group?
a group of atoms responsible for the characteristic reactions of a particular compound.
what kind of bonds do bacteria have?
ester bonds
what kind of bonds do archaea have?
ether bonds
What can archaea do that other domains can’t?
Live in extreme environments (extremophiles)
what shape is cocci
sphere shaped bacteria
what are chains of cocci called?
streptococci
what are clumps of cocci called?
staphylococci
what shape is bacilli?
rod shaped
what shape are vibrios
comma shaped
Spirochetes
spiral-shaped bacteria that have flexible walls and are capable of movement
spirilli
spiral shaped bacteria; rigid
what controls bacteria cell shape?
cytoskeletal proteins (MreB and Ftz)
what is a biofilm
collection of microbes living on a surface in a complex community
What is quorum sensing?
the ability of bacteria in a biofilm to communicate with each other and coordinate their activities
what is Gram-positive bacteria
Bacteria that have complex cell walls with thick peptidoglycan but with teichoic acids.
what are sugars attached to a protein called?
glycoprotein
When can a bacteria not be phagocytized?
when it has a capsule of mucilage
where does mucilage come from?
secreted by cells
what is a lose mucilage layer called?
slime layer
why can’t encapsulated bacteria be phagocytized
cells are too slippery to be held on to.
what does mucilage allow for cell communication?
allows quorum sensing and community between multiple species of cells.
what is the form of biofilm?
adhesive, oozing, communitive.
what is peptidoglycan?
a network of sugar polymers cross-linked by polypeptides
what do archaea lack in their cell walls?
peptidoglycan
what do bacteria have in their cell walls?
peptidoglycan
what is peptidoglycan called in bacteria?
murein
what is peptidoglycan called in archaea?
psuedomurein
Why are gram positive bacteria more susceptible to antibiotics?
antibiotics interfere with peptidoglycan synthesis
can GPB hold purple dye?
yes, purple dye is held in thick layers.
what does mordant do?
it facilitates further interactions between the primary dye & the cell wall. It will crystalize the dye that has penetrated the microbe.
what is the wall structure of a gram negative bacteria?
thinner peptidoglycan layer, enclosed in a thin outer envelope; envelope is rich with liposaccharides.
what are liposaccharides?
lipids that have polysaccharides covalently attached to them.
are gram negative cell walls sensitive to antibiotics?
Mostly resistant, but impedes secretion of proteins from outside bacteria.
what are teichoic acids?
gram positive possessing and negatively charged.
how do you treat GNB?
Stop GNB growth.
Why can’t you kill GNB?
it will cause shock; high mortality rate.
how is the cell wall constructed?
lattice; NAG sugars form chains and peptides create a bridge; many layers in order to form a wall.
how many cell wall layers in GNB?
few layers but large periplasmic space
how many cell wall layers in GPB?
many layers but small periplasmic space
what is periplasmic space?
Space between outer membrane and inner membrane (including the peptidoglycan and periplasm, gel between membranes)
what do antibiotics do to the cell wall?
break apart peptic chains
are there gaps in cell wall lattice?
yes, for nutrients.
what is motility?
movement
what are endospores?
DNA enclosure of bacteria cells that are released when a bacterial cell dies and breaks down.
what do all cells have on the surfaces?
sugars
what are proteins with a sugar attached called?
glycoproteins
what part of the cell makes contact with other cells?
the sugar
where are sugars in terms of the cell?
on the outside, never on the inside.
What is horizontal gene transfer?
process where an organism receives genetic material from another organism w/o being offspring.
what is transduction?
the process by which a virus transfers genetic material from one bacterium to another.
what is transformation?
process in which one strain of bacteria is changed by a gene or genes from another strain of bacteria.
what is conjugation?
gene transfer through direct contact.
what is vertical evolution?
gene transfer from parent to offspring.
what does smaller cell size allow?
faster cell division, but limits cell storage.
what are the properties of teichoic acids?
-thread together layers of peptidoglycan
-negatively charged –> retains basic dyes
-found in gram +
what are the charge of the heads in a phospholipid bilayer?
Polar, hydrophilic, positive charge.
what are the charge of the tails in phospholipid bilayer?
tails are hydrophobic.
what allows for cell membrane stability?
rigid carbon structures
what do ether bonds allow?
more durability in extreme environments.
what are the components of a flagella?
hook in plasma membrane, protein-chain filament tail, and motor.
how do flagella know how to swim?
sensors bind to molecule, which sends a signal to nucleus, which sends a signal for tail to spin in the direction of the molecules.
What are pili and fimbriae?
Hair-like porjections of cell, composed of pilin.
Common pili: around the cell, important to adhesion to host cell surface
Sex pilus: connection between another cell, transfer DNA
what bacteria have pili?
Gram negative
what are akinetes?
large, oval, dense, spore-like cells that allow blue-green bacteria to survive adverse conditions
what are endospores functions?
Stores genetic material in harsh conditions and facilitates survival. Once conditions are restored it goes back to being a vegetative cell. ONLY PROKARYOTIC
what are injectosomes?
Gram negative bacteria that use needles that inject proteins into the host
what are thylakoids?
ingrowths of PM that increase SA for photosynthesis.
what are inclusion bodies?
Bodies present in nucleus or cytoplasm of certain cells in infection by filterable viruses
what are magnetosomes?
magnetic storage inclusions; act like a compass to locate low oxygen habitats.
what are metachromatic granules?
Reserves of inorganic phosphate to be used for ATP synthesis & stain red with methylene blue dye
what are polysaccharide granules?
stores sugars
what are lipid inclusions?
they are reserves for lipids and fats for energy.
what are gas vacuoles?
found in aquatic, photosynthetic bacteria and archaea; provide buoyancy.
what makes bacterial DNA unique?
plasmids, circular DNA portions, no introns, contain a few thousand genes, smaller (compacted) chromosomes, single origin of replication, mostly structural genes, no histones.
how is bacterial DNA coiled if they have no histones?
compacted in loop domains then super coiled.
Alveolata examples
ciliophora, apicomplexa, dinozoa
Stramenopila
Strawlike flagellar hairs; secondary plastids (when present) derived from red algae; fucoxanthin accessory pigment common in autotrophic forms
rhizaria
thin, cytoplasmic projections; secondary plastids (when present) derived from endosymbiotic green algae
examples of amoebozoans
dictyostelia
excavata
have feeding grooves, flagellates, unicellular
examples of excavata
metamonada, kinetoplastea, euglenida
land plants and relatives
have primary plastids derived from cyanobacteria with two envelope membranes.
land plants and relatives examples
red and green algae, land plant kingdom
alveolata
the presence of cortical alveoli, small vesicles that store calcium ions.
examples of stramenopiles
diatoms, brown algae, fungus like
examples of rhizaria
chlorarachniophyta; radiolaria; foraminifera
amoebozoa
amoeboid movement by pseudopodia
Ophisthokonts
swimming cells possess a single posterior flagellum
what is reductive evolution?
the process by which microorganisms remove genes from their genome.
what is convergent evolution
the process whereby distantly related organisms independently evolve similar traits to adapt to similar necessities.
what did endosymbiosis give rise to
mitochondria and chloroplasts
what are the two types of protists
plant-like and animal-like
how is algae defined as
a unicellular plant that doesn’t have a stem or root.
what is primary endosymbiosis
heterotrophic host cells captured cyanobacterial cells via phagocytosis, but did not digest them.
how many membranes in primary endosymbiosis
two
examples of primary endosymbiosis
green and red algae
what happens to the organelles in endosymbiosis
Becomes part of the organelles of the cell.
what does the mitochindria have of it’s own
DNA
what do endosymbiotic cyanobacteria do
provided host cells with photosynthetic capacity and other useful biochemical pathways.
what did endosymbiotic cyanobacteria give rise to
primary plastids
what is secondary endosymbiosis?
when a cell is taken up entirely by another cell/organism and lives.
can a cell that already took in 1 cell take in another in secondary endosymbiosis?
yes
what happens to the nuclues in the ingested cell in 2nd ESB?
The nucleus from the ingested cell is no longer and becomes the nucleomorph (vestigial nucleus).
what is the nucleus of the ingesting cell called?
cryptophyte.
can cells in 2 ESB be photosynthetic?
yes
how many membrane layers in 2 ESB
3
examples of 2 ESB
brown algae and diatoms
what is tertiary ESB
a cell that has already ingested a cell is ingested by another cell.
what happens to the ingested cells in 3 ESB
they are eventually digested
what are kleptoplastids
the behavior of taking chloroplasts from a food source and incorporating them into the consumer’s cells.
what is a mixotroph
secondary endosymbiosis that takes up photosynthesis and can phagocytose.
what is a phagotroph
Any heterotrophic organism that feeds by ingesting organisms or organic particles, which are digested within its body.
what is a osmotroph
feeding mechanism involving the movement of dissolved organic compounds by osmosis for nutrition
what is primary plastid
enclosed envelope made of two membranes.
phytoplankton
phototrophic (plant-like). Algae and photosynthetic bacteria
Protozoan plankton
heterotrophic (animal-like or heteroplankton) also called zooplankton.
protozoan plankton
heterotrophic (animal-like or heteroplankton) also called zooplankton.
what does plankton refer to?
eukaryotic cells
Diploid
2n
haploid
n; cells are called gametes
what is a sporophye
(in the life cycle of plants with alternating generations) the asexual and usually diploid phase, producing spores from which the gametophyte arises.
gametophyte
haploid in nature
what is alternations of generations?
switching back and forth between sexual and asexual reproduction in a single organism.
what color will an organism be if closest to the surface of the water?
green
what color will organisms be if at the bottom
red
when is cilia found
eukaryotic cells
when is fimbriae found
prokaryotic cells
what is periphyton
attached by mucilage to underwater surfaces (seaweeds)
what is budding?
small part of the parent cell.
what is fission?
equally-sized divided cell.
what is schizogony
many rounds of mitosis within the parent cell, then divides all at once.
aseptate fungi properties
multinucleate; nuclei divide/mitosis without cytokinesis; good for sharing nutrients; thin wall for easy ‘eating’; chitin cell wall; membrane vesicles from ER fuse with the PM.
what is mycelium
a mass of hyphae
properties of septate fungi
each cell has one or two nuclei; nuclear division without cytokinesis; Coenocytic hyphae
what is dimorphic fungi
spore-producing hyphae in the soil.
Transform into pathogenic yeasts when mammals inhale their wind-dispersed spores.
Host body temperature triggers the change from hyphal to yeast form
how many chitin layers in yeast
1 or 2; mostly made of glucan
what is lichen
a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship
what are the three major lichens
crustose, foliose, fruticose
what are photosynthetic partners
provide organic food molecules and oxygen
what are fungal partners
provide carbon dioxide, water, and minerals
what is Mycorrhizae
fungi at plant roots to help gain nutrition
what is Endomycorrhizae
Fungal hyphae penetrate the spaces between root cell walls and plasma membranes and grow along the outer surface of the PM.
properties of endomycorhhizae
high SA due to forked branches
properties of Ectomycorrhizae
Coat the root surface and grow between cells of roots.
Some species of oak, beech, pince and spruce will not grow unless their EMR partners are also present.
Fungal endophytes properties
Live within the leaf and stem tissues of various plants.
Endophytes obtain organic molecules from plants.
In turn, they contribute toxins or antibiotics that deter foraging animals, insect pests, and microbial pathogens.
Plants with endophytes often grow better than plants of the same species without.
what is a sporophyte
Multicellular diploid organism
what is a gametophyte
Multicellular haploid organism
what species of alternation of generations occur in
plants and some algae, fungi
what is a sporangium
an enclosure in which spores are formed. It can be composed of a single cell or can be multicellular.
what is sporangiospores
The asexual propagules that form inside a sporangium, which can be mostly spherical or cylindrical, through a process involving cleavage of the cytoplasm
what is a gametangium
hyphae with gametes that fuse with mate to form zygospores (diploid). Then the sac that is formed when mated breaks open, releasing zygospores.
what are zygospores
have two nuclei but they do not fuse. But when it grows into hypha, it combines.
what do -phytes imply
plants/habitats
what does -trophy imply
nutrition or energy source
what is the plasmodesmada
the channels between two plant cells for nutrition and endoplasmic reticulum sharing.
what are bryophytes
nonvascular plants; no xylem and phloem
what are the characteristics of life
Cellular organization, the ability to reproduce, growth & development, energy use, homeostasis, response to their environment, and the ability to adapt.
