Ch 13 NSC

Plasmodium is a(n)...

apricomplexan

Which is an example of a benefit attributed to bacteria?

bacteria in the human gut and vagina prevent the growth of pathogens.

cholera

diarrheal illness

Both mitochondria and chloroplasts are thought to have evolved by the process of _____.

endosymbiosis

Ebola

enveloped RNA virus that emerged in Africa, infected fruit bats and non-human primates.

protist

general term for eukaryote that is not a fungus, plant, or animal

Water molds

heterotrophic protist that forms a mesh of nutrient-absorbing filaments.

Plasmodial slime molds

heterotrophic protist that moves and feeds as a multi-nucleated mass; forms a fruiting body when conditions are unfavorable.

Cellular Slime Molds

heterotrophic protist that usually lives as a single-celled, amoeba-like predator. When conditions are unfavorable, cells aggregate into a cohesive group that can form a fruiting body.

Choanoflagellates

heterotrophic protists with a collared flagellum; protist group most closely related to animals.

foraminiferan (forams)

heterotrophic single-celled protist that secretes a calcium carbonate shell

Endosymbiont hypothesis

hypothesis that mitochondria and chloroplasts evolved from free-living bacteria that entered and lived inside another cell.

contractile vacuole

in freshwater protists, an organelle that collects and expels excess water.

bioluminescence

light produced by a living organism

transformation

mechanism of gene transfer. A prokaryotic cell takes up and uses DNA from its environment.

conjugation

mechanism of gene transfer. One prokaryotic cell directly transfers a plasmid to another.

______ may have been a source of organic monomers on early earth

meteorites

binary fission

method of asexual reproduction in which a prokaryote divides into two identical descendant cells.

bacteria

most diverse and well-known lineage of prokaryotes

Brown algae

multi-celled, photosynthetic protist with brown accessory pigments

Bacteriophage (phages)

non-enveloped virus that infects bacteria

Plant Virus

non-enveloped with a helical structure and a genome of single-stranded RNA.

Viral Reassortment

occurs when two related viruses that infect the same host as the same time, can lead tot eh emergence of new viral strains.

Plasmid

of many prokaryotes, a small ring of non-chromosomal DNA.

Experiments like those performed by Stanley Miller in the 1850s demonstrated that lightening fueled atmospheric reactions could produce________.

organic compounds required for life under artificial conditions.

multicellular organism

organism composed of a variety of specialized cells, each unable to survive and reproduce on its own.

Colonial organism

organism composed of many integrated cells, each capable of surviving and reproducing on its own

decomposer

organism that breaks down organic material into its inorganic subunits

disease vector

organism that carries a pathogen from one host to the next.

extreme halophiles

organism that lives where the salt concentration is high

heterotroph

organism that obtains both carbon and energy by breaking down organic compounds.

methanogens

organism that produces methane gas as a metabolic by-product

Extreme thermophiles

organisms that lives where the temperature is very high

The appearance of _______- on earth due to the action of photosynthetic bacteria occurred about 2.7 billion years ago.

oxygen

apicomplexan

parasitic protist that enters and lives inside the cells of its host.

The ______ of flagellated protozoans are analogous to the _____ of prokaryotes.

pellicle; cell wall

The ____ water mold was responsible for the Irish famine in the mid-1800s.

phytophthora

algal bloom

population explosion of single-celled aquatic organisms such as dinoflagellates.

Nitrogen fixation

process of combining nitrogen gas with hydrogen to form ammonia.

Francis Crick and Leslie Orgel

proposed the RNA world hypothesis

G. lamblia infection in the gut ______; therefore, some people may be benefited by the presence of this protist.

reduces the risk of parasitic worm infection

Gonorrhea

sexually transmitted disease

Red algae

single-celled or multi-celled photosynthetic protist with red accessory pigment

Diatoms

single-celled photosynthetic protist with brown accessory pigments and a two-part silica shell

dinoflagellate

single-celled, aquatic protist typically with cellulose plates and two flagella, may be heterotrophic or photosynthetic

Green algae

single-celled, colonial, or multi-celled photosynthetic protist belonging to the group most closely related to land plants.

Amoebas

solitary heterotrophic protist that feeds and moves by extending pseudopods

Strep throat

sore throat, can damage heart

Examples of bacterial diseases

-whooping cough -tuberculosis -strep throat -cholera -syphilis -gonorrhea -chlamydia -lyme disease

Virus

A noncellular infectious particle with a protein coat and a genome of RNA or DNA; replicates only in living cells.

The ______ began in 2007 and aims to classify the microorganisms the human body supports and how they impact overall health

Human Microbiome project

RNA world hypothesis

Hypothesis that RNA served as the first material of inheritance

Iron-sulfur world hypothesis

Hypothesis that life began in rocks rich in iron sulfide near deep-sea hydrothermal vents.

Stanley Miller

Hypothesized that lightning fueled atmospheric reactions could produce simple organic compounds.

3 Hypotheses about the source of the organic building blocks for Earth's first life

1. Lightning fueled atmospheric reactions 2. Delivery from space via meteorites 3. Reactions at deep-sea hydrothermal vents

Process of Binary Fission

1. bacterium has one circular chromosome that attaches to the inside of the plasma membrane 2. the cell duplicates its chromosome, attaches the copy beside the original, and adds membrane and wall material between them. 3. when the cell has just about doubled in size, a new membrane and wall are deposited across its midsection 4. two genetically identical cells result.

Bacteriophage replication

1. starts when a bacteriophage attaches to a bacterial cell and injects its DNA - Pathway 1: injected host produces viral components that self-assemble as virus particles. Then a viral encoded enzyme breaks down the host's cell wall, this kills the cell and releases the viral particles into the environment - Pathway 2: DNA becomes integrated into the host cell's genome and viral genes are not immediately expressed. When the cell reproduces, viral DNA is copied and passed to the cell's descendants along with the host's genome. Now it awaits entering the lytic pathway to replicate.

Viral replication cycle

1. virus attaches to an appropriate host cell by binding to a specific protein in the host's plasma membrane 2. Then the viral genome or another viral component enters into the cell 3. The Viral genes take over a host's cellular machinery 4. viral components self-assemble to form new viral particles 5. These particles are released from the infectious cell when the cell bursts, or they may bud from the host cell taking pieces of the plasma membrane with them.

Ozone layer

Atmospheric layer with a high concentration of ozone that prevents much UV radiation from reaching Earth's surface.

Flu

Caused by enveloped RNA viruses called influenza viruses.

_____ are believed to have once existed as independent prokaryotes.

Chloroplasts

Microbiome

Collection of microorganisms that inhabits a specific habitat, such as a human body.

Hydrothermal vent

Underwater opening from which mineral-rich water heated by geothermal energy streams out.

Pathogen

Disease-causing agent

Stromatolites

Dome-shaped structures composed of layers of prokaryotic cells and sediments; forms in shallow seas.

_____ is the best studied species of bacteria.

E. Coli

HIV (human immunodeficiency virus)

Enveloped RNA virus that causes AIDS and replicates inside human white blood cells. Infected non-human primates evolved in Africa where it made its way to Haiti where it diversified.

Archaea

Lineage of prokaryotes most closely related to eukaryotes; many live in extreme environments

Transduction

Mechanism of gene transfer. A virus moves genes from one host cell to another

Protocell

Membranous sac that contains interacting organic molecules; hypothesized to have formed prior to the earliest cells.

Autotroph

Organism that uses carbon dioxide as its carbon source; obtains energy from light or break-down of minerals

_______ allow bacteria to join together to transfer genes.

Pili

Two researchers suggested in the 1960s that _____ may have been the first informational molecule.

RNA

DNA is more stable than RNA for storing genetic information because ________.

RNA breaks more easily and accumulates more mutations than DNA does

Prokaryotic cells are _____.

Widespread on the planet

viral envelope

a layer of cell membrane derived from the host cell in which an enveloped virus was produced.

All free viral particles contain ....

a viral genome protected by a protein coat.

a virus is most analogous to a(n) _____.

carjacker

The _____ spend most of their lives as individual haploid organisms.

cellular slime molds

whooping cough

childhood respiratory disease

The close relationship between _____ and animals can be seen in the similarity of these protists and sponges, simple animals.

choanoflagellates

Scientists hypothesize that _______ served as a primitive template for forming polymer chains from organic subunits, such as amino acids.

clay particles in tidal flats

plankton

community of mostly microscopic drifting or swimming organisms

Evidence supporting the lack of oxygen on early Earth includes ______.

the lack of iron oxidation on ancient rocks

you boil water that has been extracted from a swamp and find archaea that are still alive. These archaea are most likely ______.

thermophiles

Halophiles

these can live in water of very high salt concentration

bacteria

these have parasitic members.

Thermophiles

these live in temperatures that are not usually conducive to life.

Methanogens

these produce methane

Viral reassortment

two viruses of the same type infect an individual at the same time and swap genes.

flagellated protozoan

unwalled, single-celled protist that has one or more flagella

Ciliate

unwalled, single-celled protist with many cilia