Viruses

Question 1

capsid

Answer 1

a protein shell that encloses and protects the genetic material of a virus

Question 2

capsomeres

Answer 2

protein subunits that make up a capsid / outer shell of a virus

Question 3

virus

Answer 3

” a kind of borrowed between life-forms & chemicals

Question 4

True of False: Viruses are NOT cells

Answer 4

true

Question 5

viruses consists of:

Answer 5

nucleic acid enclosed in a protein coat and sometimes a membranous envelope

Question 6

host range

Question 7

viruses are obligate intercellular parasites that can ….

Answer 7

replicate only within a host cell

Question 8

Bacteriophages

Answer 8

infect bacteria

Question 9

lytic cycle

Answer 9

phage replicative cycle that culminates in the DEATH of the host cell

Question 10

lysogenic cycle

Answer 10

replicates the phage genome WITHOUT destroying the host

Question 11

lytic cycle produces…

Answer 11

new phages and beaks down the host’s cell wall = releasing the progeny viruses

Question 12

The viral DNA molecule is incorporated into the host cell’s chromosomes

Answer 12

Lysogenic cycle

Question 13

The 2 key variables used to classify the viruses that infect animals

Answer 13

1) Nucleic acid (DNA/RNA)
2) single stranded / double stranded

Question 14

Retrovirus

Answer 14

• infects animals
• REVERSE TRANSCRIPTS to copy their RNA genome into DNA

Question 15

provirus

Answer 15

viral DNA that is integrated into the host genome

Question 16

prokaryotic cell shapes

Answer 16

• spheres (cocci)
• rods (bacilli)
• spirals

Question 17

Cell wall

Answer 17

maintains cell shape and protects the cell

Question 18

Bacterial cell walls contain…

Answer 18

peptidoglycan

Question 19

peptidoglycan

Answer 19

a network of sugar polymers cross-linked by polypeptides

Question 20

archaea

Answer 20

contains polysaccharides and proteins but lack peptidoglycan

Question 21

We use gram stains to …

Answer 21

classify bacteria by cell wall comparison

Question 22

gram positive

Answer 22

• pink stain
• bacteria have simpler cell walls with a large about of peptidoglycan

Question 23

gram negative

Answer 23

• violet stain
• bacteria have less peptidoglycan and an outer membrane that can be toxic

Question 24

which gram-______ is more likely to be antibiotic resistant

Answer 24

gram-negative

Question 25

capsule

Answer 25

a polysaccharide (protein layer) that covers many prokaryotes

Question 26

reproduction in bacteria

Answer 26

- prokaryotic genome DNA < eukaryotic genome - circular chromosome (not surrounded by a membrane) and located in the nucleoid region) - some have plasmids

Question 27

plasmid

Answer 27

smaller rings of DNA

Question 28

Reproduction & Adaptation

Answer 28

- reproduce by binary fission (divide every 1-3 hours - form metabolically inactive endospores

Question 29

binary fission

Question 30

endospores

Answer 30

dormant, can remain viable in harsh conditions for centruries

Question 31

Nitrogen is essential for the productions of...

Answer 31

amino acids and nucleic acids

Question 32

True or False: Prokaryotes can metabolize nitrogen in a variety of ways

Answer 32

TRUE

Question 33

nitrogen fixation

Answer 33

some prokaryotes convert atmospheric nitrogen to ammonia

Question 34

some Archaea live in extreme environments called...

Answer 34

Extremophiles

Question 35

extreme halophiles

Answer 35

lives in highly saline environments (high salt concentration)

Question 36

extreme thermophiles

Answer 36

thrive in very hot environments

Question 37

Methanogens (arhcaea)

Answer 37

- produces methane gas - lives in swamps / marshes

Question 38

conjugation

Answer 38

the process where genetic material is transferred between prokaryotic cells

Question 39

pilus

Answer 39

a donar cell attaches to a recipient by a pilus pulls it closer and transfers DNA

Question 40

phototrophs

Answer 40

obtains energy from light

Question 41

chemotrophs

Answer 41

obtains energy from chemicals

Question 42

autotrophs

Answer 42

requires CO2 as a carbon source

Question 43

heterotrophs

Answer 43

requires an organic nutrient to make organic compounds

Question 44

obligate aerobes

Answer 44

require O2 for cellular respiration

Question 45

obligate anaerobes

Answer 45

poisoned by O2 and use fermantation (or anaerobic respiration)

Question 46

facultative anaerobes

Answer 46

can survive with or without CO2

Question 47

transformation

Answer 47

incorporate foreign DNA from surrounding environment

Question 48

transduction

Answer 48

movement of genes between bacteria by bacteriophages (viruses that infect bacteria)