Chapter 17, 20, 24

Question 1

What are the 3 domains of life?

Answer 1

Bacteria, archaea, and eukaryota. Eukaryota are animals, plants, fungi, and protists).

Question 2

Capsid

Answer 2

The protein shell that encloses a viral genome. It may be rod-shaped, polyhedral, or more complex in shape.

Question 3

How may a viruses genome be?

Answer 3

Double/single stranded DNA and double/single stranded DNA

Question 4

Viral envelope

Answer 4

A membrane, derived from membranes of the host cell, that cloaks the capsid, which in turn encloses a viral genome.

Question 5

Bacteriophage

Answer 5

A virus that infects bacteria; also called a phage.

Question 6

Host range

Answer 6

The limited number of species whose cells can be infected by a particular virus.

Question 7

Lytic cycle

Answer 7

A type of phage replicative cycle resulting in the release of new phages by lysis (and death) of the host cell.

Question 8

Lysogenic cycle

Answer 8

A type of phage replicative cycle in which the viral genome becomes incorporated into the bacterial host chromosome as a prophage, is replicated along with the chromosome, and does not kill the host.

Question 9

Virulent phage

Answer 9

A phage that replicates only by a lytic cycle.

Question 10

Give a brief summary of the lytic cycle steps

Answer 10

1) Attachment 2) Entry of phage DNA and degradation of host DNA 3) Synthesis of viral genomes and proteins 4) Assembly 5) Release

Question 11

Restriction enzyme

Answer 11

An endonuclease (type of enzyme) that recognizes and cuts DNA molecules foreign to a bacterium (such as phage genomes). The enzyme cuts at specific nucleotide sequences (restriction sites).

Question 12

Temperate phage

Answer 12

A phage that is capable of replicating by either a lytic or lysogenic cycle.

Question 13

Prophage

Answer 13

A phage genome that has been inserted into a specific site on a bacterial chromosome.

Question 14

Phylogeny

Answer 14

The evolutionary history of a species or group of related species.

Question 15

Systematics

Answer 15

A scientific discipline focused on classifying organisms and determining their evolutionary relationships.

Question 16

Taxonomy

Answer 16

A scientific discipline concerned with naming and classifying the diverse forms of life.

Question 17

Binomial

Answer 17

A common term for the two-part, latinized format for naming a species, consisting of the genus and specific epithet; also called a binomen.

Question 18

How does the naming system go?

Answer 18

Genus —> species

Question 19

Genus

Answer 19

taxonomic category above the species level, designated by the first word of a species’ two-part scientific name.

Question 20

What is the order of the Linnaean system?

Answer 20

Kingdom –> Phylum –> Class –> Order –> Family –> Genus –> Species

Question 21

What are Archaea?

Answer 21

These are ancient forms of bacteria that were originally grouped under the kingdom Monera (now defunct) as Archaeabacteria. They are single celled microbes that find their origins as the first organisms of life here on Earth. Hence we give them the prefix ‘archaea’, which in Greek means ‘ancient things.’ Archaea organisms are also different from other domains in that many are extremophiles, meaning they can live in intense environments with high temperature, high acid, and high salt levels. One type of extremophile is the methanogens, or those organism that produce methane as a product of their metabolism.

Question 22

Who are Miller and Urey and what did they do?

Answer 22

Miller and Urey made early earth in a lab. They simulated the conditions on early earth. They simulated water evaporating, electors which equaled lighting and also prebiotic soup. Result: amino acids formed

Question 23

Describe early earth

Answer 23

Early earth didn’t have clear water and oceans, it didn’t have plants, there was no life at all. The sun was weaker and the atmosphere was thicker and dominated by CO2.

Question 24

What was the environment for first life?

Answer 24

Consisted of hydrogen sulfide.

Question 25

What are the ingredients of life?

Answer 25

Hydrogen, oxygen, carbon, and nitrogen.

Question 26

What are Cyanobacteria?

Answer 26

They are bacteria on top of stromatolites and they are blue/green. They use photosynthesis as energy. As stuff settles on top the bacteria move up. Cyanobacteria made oxygen to produce the oxygenated atmosphere on earth.

Question 27

Talk about Cyanobacteria part 2

Answer 27

Cyanobacteria obtain their energy through photosynthesis.

Question 28

Earth earth with oxidizing vs reducing

Answer 28

By producing gaseous oxygen as a byproduct of photosynthesis, cyanobacteria are thought to have converted the early reducing atmosphere into an oxidizing one, causing the "rusting of the Earth"[7] and causing the Great Oxygenation Event, dramatically changing the composition of life forms on Earth by stimulating biodiversity and leading to the near-extinction of anaerobic organisms (that is, oxygen-intolerant). Symbiogenesis argues that the chloroplasts found in plants and eukaryotic algae evolved from cyanobacterial ancestors via endosymbiosis.

Question 29

Abiotic

Answer 29

Nonliving; referring to the physical and chemical properties of an environment.

Question 30

Probiotic

Answer 30

Denoting a substance that stimulates growth of micro organisms, especially those with beneficial properties

Question 31

Protocells

Answer 31

An abiotic precursor of a living cell that had a membrane-like structure and that maintained an internal chemistry different from that of its surroundings.

Question 32

What are the earliest fossils?

Answer 32

They are of prokaryotes that lived 3.5 billion years ago

Question 33

Simple cells were produced through what 4 main stages?

Answer 33

1) The abiotic (nonliving) synthesis of small organic molecules, such as amino acids and nitrogenous bases. 2) The joining of these small molecules into macromolecules, such as proteins and nucleic acids. 3) The packaging of these molecules into protocells, droplets with membranes that maintained an internal chemistry different from that of their surroundings. 4) The origin of self-replicating molecules that eventually made inheritance possible.

Question 34

Stromatolites

Answer 34

Stromatolites are many of the oldest known fossils that are layered rocks that form the activities of certain prokaryotes.

Question 35

Gram positive

Answer 35

Describing the group of bacteria that have a cell wall that is structurally less complex and contains more peptidoglycan than the cell wall of gram-negative bacteria. Gram-positive bacteria are usually less toxic than gram-negative bacteria.

Question 36

Gram negative

Answer 36

Describing the group of bacteria that have a cell wall that is structurally more complex and contains less peptidoglycan than the cell wall of gram-positive bacteria. Gram-negative bacteria are often more toxic than gram-positive bacteria.

Question 37

Gram positive bacteria with gram staining

Answer 37

Gram positive bacteria stain a darker color and have a thick cell wall made of peptidoglycan

Question 38

Gram negative bacteria with gram staining

Answer 38

Gram negative bacteria have a thinner layer of peptidoglycan located between the plasma membrane and the outer membrane

Question 39

Peptidoglycan

Answer 39

A type of polymer in bacterial cell walls consisting of modified sugars cross-linked by short polypeptides. Peptidoglycan encloses the entire bacterium and anchors other molecules that extend from its surface.

Question 40

Endospores

Answer 40

A thick-coated, resistant cell produced by some bacterial cells when they are exposed to harsh conditions.

Question 41

Capsule

Answer 41

(1) In many prokaryotes, a dense and well-defined layer of polysaccharide or protein that surrounds the cell wall and is sticky, protecting the cell and enabling it to adhere to substrates or other cells. (2) The sporangium of a bryophyte (moss, liverwort, or hornwort).

Question 42

Endosymbiosis

Answer 42

A mutually beneficial relationship between two species in which one organism lives inside the cell or cells of another organism.

Question 43

Role of RNA

Answer 43

First way of passing down and storing information information.

Question 44

Transformation

Answer 44

(1) The conversion of a normal animal cell to a cancerous cell. (2) A change in genotype and phenotype due to the assimilation of external DNA by a cell. When the external DNA is from a member of a different species, transformation results in horizontal gene transfer.

Question 45

Conjugation

Answer 45

(1) In prokaryotes, the direct transfer of DNA between two cells that are temporarily joined. When the two cells are members of different species, conjugation results in horizontal gene transfer. (2) In ciliates, a sexual process in which two cells exchange haploid micronuclei but do not reproduce.

Question 46

Binary fission

Answer 46

A method of asexual reproduction by “division in half.” In prokaryotes, binary fission does not involve mitosis, but in single-celled eukaryotes that undergo binary fission, mitosis is part of the process.

Question 47

Compare binary fission and conjugation

Answer 47

Both reproduce& replicate DNA, maybe plasmids, gene transfer, produce offspring

Question 48

Contrast binary fission and conjugation

Answer 48

Conjugation: sexual reproduction (2 parents), 1 cell can't continue species survival, reproduces slowly, has F-factor, produces different offsprings-genetic diversity Binary fission: asexual reproduction (1 parent), produces identical offsprings, 1 cell can continue species survival, no F-factor, reproduces quickly

Question 49

Quorum sensing

Answer 49

Instead of language, bacteria use signalling molecules which are released into the environment. As well as releasing the signalling molecules, bacteria are also able to measure the number (concentration) of the molecules within a population. Nowadays we use the term 'Quorum Sensing' (QS) to describe the phenomenon whereby the accumulation of signalling molecules enable a single cell to sense the number of bacteria (cell density). In the natural environment, there are many different bacteria living together which use various classes of signalling molecules. As they employ different languages they cannot necessarily talk to all other bacteria.

Question 50

Bacteria

Answer 50

Bacteria are tiny living beings (microorganisms) - they are neither plants nor animals - they belong to a group all by themselves. Bacteria are tiny single-cell microorganisms, usually a few micrometers in length that normally exist together in millions.

Question 51

How do antibiotics work?

Answer 51

Antibiotics work by blocking vital processes in bacteria, killing the bacteria, or stopping them from multiplying. This helps the body's natural immune system to fight the bacterial infection.

Question 52

What are antibiotics?

Answer 52

Antibiotics are medicines used to treat infections or diseases caused by bacteria (e.g. respiratory tract infections such as pneumonia and whooping cough).

Question 53

Domain

Answer 53

(1) A taxonomic category above the kingdom level. The three domains are Archaea, Bacteria, and Eukarya. (2) A discrete structural and functional region of a protein.

Question 54

Bacteria

Answer 54

type of prokaryotic organism Identified by their: 1) shape 2) chemical nature of their cell walls 3) they ways they move 4) the ways they obtain energy

Question 55

How do bacteria reproduce?

Answer 55

1st way: binary fission | 2nd way: conjugation

Question 56

What do cladogram so use for grouping?

Answer 56

Cladograms use patterns of shared derived characters as the main criteria for grouping.

Question 57

Describe the earliest life forms on earth

Answer 57

Prokaryotic cells with metabolism based on chemosynthesis

Question 58

What are the steps to the formation of life on earth; as it involves Protocells

Answer 58

Protocells are cells that are the step before life that make a membrane bound structure. First thing made on earth were amino acids (monomers) which made polymers. Polymers then go to protobions which then go to prokaryotic structures and then to eukaryotic structures.