test 2 terms

Question 1

operon

Answer 1

functioning unit of genomic DNA containing cluster of genes under control of a single promoter

Question 2

mutation

Answer 2

change in genetic material permanent change in the base of sequence or DNA, could be beneficial or harmful

Question 3

genotype

Answer 3

genes or genetic makeup of an organisms, all the DNA

Question 4

phenotype

Answer 4

expression of genes, what we see

Question 5

constitutive genes

Answer 5

genes that are expressed all of the time, genes that are always being produced (ribosome)

Question 6

transposons

Answer 6

small segments of DNA that can move from one region of DNA molecule to another, can leap from one chromosome to another

Question 7

transformation

Answer 7

genes are transferred from one bacterium to another as “naked” DNA in a solution

Question 8

gene

Answer 8

a segment of DNA encoding a functional product

Question 9

mutagen

Answer 9

agent that causes mutations

Question 10

codons

Answer 10

sequence of three nucleotides that specifies the insertion of a specific amino acid

Question 11

inducible genes

Answer 11

initiates transcription; “off” mode, turned on by environment inducer

Question 12

repressible genes

Answer 12

inhibits gene expression; “on” mode, turned off by environmental compressor and repressor

Question 13

sepsis

Answer 13

refers to microbial contamination

Question 14

autoclave

Answer 14

steam under pressure with high heat, equipment used for sterilization by steam

Question 15

psychrotrophs

Answer 15

grow between 0C and 20-30C, cause food spoilage

Question 16

biofilms

Answer 16

microbial communities, form slime or hydrogels, share nutrients, sheltered from harmful factors

Question 17

lypophilization

Answer 17

freeze dry- frozen and dehydrated in a vacuum, -54C to -72C

Question 18

generation time

Answer 18

time required for a cell or population to double in number

Question 19

colony forming unit

Answer 19

visible bacterial colonies on solid media, one singular colony

Question 20

bacterial colony

Answer 20

population of cells arising from a single cell or spore or from a group of attached cells

Question 21

selective media

Answer 21

suppress unwanted microbes and encourage desired microbes

Question 22

reducing media

Answer 22

contain chemicals that combine with dissolved O2 and deplete the O2 in that medium