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bacillus

is a prokaryotic cell with a rod shape

coccus

a spherical bacterial cell

this type of bacteria can appear in many different shapes

Spiral shaped

Vibrios

comma shaped spiral shaped

vibrios

helical spiral shaped

spirochete

last type of

streptobacillus

chain of rod bacteria

diplococcus

pair of joined spherical bacteria

tetrad

group of four spherical bacteria

staphylococcus

cluster of spherical bacteria

streptococcus

chain of spherical bacteria

the structure and organization of bacteria are based on

specific processes call need to carry out

the processes cells need to carry out are

sensing/responding to stimuli, compartmentation of metabolism, growth reproduction

bacterial flagella

Are long appendages extending from the cell surface

flagella can be used for

motility

bacterial flagella contain

helical filament, a hook, and a basal body and move in a circular movement

Bacteria exhibit ______, moving up the concentration gradient of a chemical attractant

chemotaxis

monotrichous

one flagella

lophotrichous

multiple flagella coming out of one end of a bacteria

amphitrichous

flagella coming out of both ends of a bacteria

peritichous

flagella coming out of a bacteria everywhere

pili

Are protein fibers extending from the surface of many bacteria

pili help

attach cells to surfaces, to form biofilms and microcolonies

Some bacterial species have _______, used to transfer genetic material between cells

conjugation pili

Glycocalyx

is a outer layer of the cell wall

the glycocalyx is an adhering layer of _____ and some times small proteins

polysaccharides

A thick glycocalyx bound to the cell is a

capsule

A thinner, diffuse layer of polysaccharides is a

slime layer

glycocalyx protects cells from

the environment, and allows them to attach to surfaces

is a tough and protective external shell

the bacterial cell wall

the cell wall of bacteria protect the cell from

injury

the cell wall also helps the cell to

maintain its shape

what helps a bacterial cell aid in water balance

the cell wall

game positive cell walls

have a peptidoglycan structure that allows the stain to get stuck in the cell

gram negative cell walls

have an outer layer over the peptidoglycan layer that is made up of lipopolysaccharide not letting the stain into the cell wall

Cell walls in bacteria contain

peptidoglycan

Gram-positive bacteria have _____ peptidoglycan cell walls containing teichoic acid

thick

Gram-negative bacteria have

a two-dimensional peptidoglycan layer and no teichoic acid

has an outer membrane, separated from the cell membrane by the periplasmic space

The gram-negative cell wall

The outer membrane of _____ contains proteins called porins that selectively allow small molecules into the periplasmic space

gram negative

peptidoglycan in gram positive cells

is a thick layer

peptidoglycan in gram negative cells

is a thin layer

only _____ contain teichoic acid

gram positive

Only _____ contain a outer membrane, lipopolysaccharides, porin proteins, and periplasmic region

gram negative

The interface between the cell environment and the cell cytoplasm

cell membrane

cell membrane is the fluid layer of

phospholipid and protein

The phospholipid molecules are arranged in a

bilayer

Hydrophobic fatty acid chains in the phospholipids form a

permeability barrier

cell membranes can aid in

Cell wall synthesis, Energy metabolism, DNA replication, Sensation of stimuli, Molecule transport

_____ substances may disrupt or dissolve the bilayer

antimicrobial

Several antibiotics pick on unique target structures and ______ in the membrane, resulting in death through cell lysis.

poke holes

Center of growth and metabolism is

cytoplasm

nucleotide

represents a subcompartment containing the chromosome

the chromosome

is usually a closed loop of DNA and protein

DNA contains

the genes (hereditary information)

a complete set of genes is called a

genome

most cells have only one copy of each gene which means

they are haploid and cannot undergo mitosis like eukaryotes

Damage to DNA

inevitable injures or kills the organism

DNA tells the cell

what proteins to make

proteins facilitate

cellular functions

some proteins are

enzymes that catalyze biochemical reactions and vital to metabolism

protein roles

structural, mechanical, cell signaling, immune responses, cell adhesion, cell cycle

plasmids are

Molecules of DNA smaller than the chromosome

Each plasmid is a closed loop, containing

5-100 genes

Plasmids can be transferred between

cells

R plasmids carry

genes for resistance to antibiotics

plasmids can be used

in genetic engineering

There are hundreds of thousands of _____, used for protein synthesis

ribosomes

Inclusion bodies

store nutrients or building blocks for cellular structures

Some aquatic bacteria use _______ to float on the water's surface

gas vesicles

magneotsomes

contain crystals of magnetite or greigite, allowing cells to respond to magnetic fields

bacteria can reproduces by

binary fission

when bacteria reproduce the cell

doubles in mass

the DNA then replicates into _____ once the cell has doubled in mass

two strands

cytokinesis is

aninward pinching of the cell membrane and cell wall to separate the cell into two genetically identical cells

binary fission

1) cell elongates/ DNA replicates
2) cell wall and plasmid membrane begin to invaginate
3)cross wall forms two distinct cells
4) cell seperates

Asexual reproduction can also

be preformed by bacteria

The generation (or doubling) time

is the interval of time between successive binary fissions

in pathogens

ashorterdoublingtime
means a shorter incubation period of
disease

Thisconstantdoublingofthenumbers only occurs as long as nutrients for growth are available during the _____ of growth.

log phase

log phase is

exponential growth stage for bacteria

during the lag phase of bacterial growth

no cell division occurs while bacteria adapt to their new environment (1st stage)

exponential growth of the population occurs

during the logarithmic (log) pahse

Human disease symptoms usually develop during the

log phase

When reproductive and death rates equalize,

the population enters the stationary phase

The accumulation of waste products and scarcity of resources causes

the population to enter the decline (exponential death) phase

Endospores are

a highly resistant survival structure formed by species of Bacillus and Clostridium when nutrient supplies are low

spores can lay dormant

for years then germinate into a vegetative cell, withstand boiling water, alcohol and radiation

Sporulation cycle

1) bacteria replicate with 2 chromosomes present waiting for split
2)one chromosome necondenses at the end of the cell and a transverse septum separates the prespore from the mother cell
3)septum forms completely and the prespore is completely engulfed in the mother spore
4) outer layer (cortex) develops around the prespore
5) walls of spore are complete and mother cell begins to disintegrate
6) spore is released and will germinate if in present conditions once again

Step 1 of endospore creation

A stressed cell undergoes asymmetrical cell division, creating a small prespore and larger mother cell

the pre spore contains

Cytoplasm, DNA, dipicolinic acid, which stabilizes proteins and DNA

step 2 of endospore creation

Themothercellmaturesthepresporeintoanendospore,then disintegrates, freeing the spore

endospore are resistant to

desiccation, heat, and undergo very few chemical reactions

When environmental conditions are again favorable,

protective layers break down and the spore germinates into a vegetative cell

in order for bacterial to grow

Water, Carbon/energy sources, Essential elements and organic growth factors, Temperature, pH, Oxygen, Carbon dioxide, Osmotic conditions

all nutrients must be

dissolved in water to enter the cell.

Almost ______ of the cell is water.

70-90%

All cellular chemical reactions occur in

water

Drying therefore inhibits the

growth of organisms

capsules provide

some resistance to drying as moisture is trapped around the cell.

producing spores is

the ultimate way to survive drying.

phototrophs

use light as primary energy source

chemotrophs

reactions of inorganic or organic compounds for energy

autotrophs

use carbon dioxide as carbon source

heterotrophs

organic carbon source

Processes of Energy Usage

Biosynthesis of Polysaccharides, Lipids, Amino Acids, Proteins, Purine & Pyrimidine

Essential Elements & Organic Growth Factors

Glucose, salts, carbon, nitrogen, amino acids, purines, pyrimidines, vitamins

Each bacterial species has an optimal temperature for growth and about a ___ range of acceptable temperatures

30 degree

psychrophiles

grow optimally below 15°C, and make up the largest portion of all prokaryotes on Earth

thermophiles

multiply best around 60°C, living in compost heaps and hot springs

hyperthermophiles

grow optimally above 80°C, found in seafloor hot-water vents

mesophiles

thrive at the medium temperature range of 10° to 45°C, including pathogens that thrive in the human body

obligate aerobes

require oxygen to grow

microaerophilic

prefer O2 slightly lower than air

anaerobes

do not or cannot use oxygen

aerotolerant

species are insensitive to oxygen but can grow in its presence

Obligate anaerobes

are inhibited or killed by oxygen

Facultative

prokaryotes grow either with oxygen or in reduced oxygen environments

Capnophilic

bacteria require an atmosphere low in oxygen and rich in carbon dioxide (CO2)

The majority of species grow optimally at

neutral (~7.0) pH

acidophiles are

acid-tolerant prokaryotes, those used to turn milk into buttermilk, sour cream, and yogurt

barophiles

can withstand incredibly high hydrostatic pressure, psychrophiles living at the bottom of the ocean

halophiles

are salt-tolerant prokaryotes, They can maintain optimal osmotic pressure without
suffering from plasmolysis

Osmophiles

like high osmotic conditions regardless of salt or sugar.

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