Gene Expression

Question 1

Gene expression and genetic manipulation cover the three main concepts of…

Answer 1

selective breeding
whole organism cloning
transgenesis

Question 2

Genes are…

Answer 2

the unit of inheritance found on chromosomes in DNA

Question 3

Genes found on the same locus on a homologous pair of chromosomes have…

Answer 3

the genetic code fo the same characteristic

Question 4

Alleles are…

Answer 4

different forms fo a gene with slightly different base sequences of DNA

Question 5

A gene is that length of DNA that has..

Answer 5

the code for a particular protein with a sequence of a triplet coding for an amino acid

Question 6

The two processes involving amino acids turning into proteins

Answer 6

Transcription (in the nucleus using codons and mRNA)
Translation (in the cytoplasm with the ribosomes and anticodons)

Question 7

A metabolic pathway is…

Answer 7

a series of enzyme-controlled steps in which a reactant is converted into a product whcih becomes the reactant for the next step until a final product is produced

Question 8

Gene mutations (three mutations)

Answer 8

substitution (lest harmful due to code degeneracy)
deletion
insertion

Question 9

Gene mutations form new alleles so…

Answer 9

provide the raw material for evolution

Question 10

Mutations can be (four affects of mutations on natural selection)

Answer 10

Beneficial (selected for)
Neutral/silent (selection determined by chance)
Harmful (selected against)
Lethal

Question 11

DNA coding and non-coding functions

Answer 11

Coding DNA has the bases to make the amino acids.
Non-coding DNA has the instructions for which parts of the DNA are switched ‘on’ or ‘off’

Question 12

Complete dominance is…

Answer 12

when the presence of a dominant allele masks the presence of a recessive allele so the dominant allele is expressed ifn the phenotype

Question 13

incomplete dominance is…

Answer 13

neither allele is dominant and creates an intermediate blend of both phenotypes

Question 14

Co-dominance is…

Answer 14

both alleles are dominant and expressed in the offspring typically in patches of both phenotype

Question 15

Multiple allles occurs when…

Answer 15

there are more than two possible alleles for a particular gene

Question 16

Processes fo Genetic manipulation through human control:

Answer 16

selective breeding
transgenesis
whole organ cloning

Question 17

methylation of DNA is…

Answer 17

the adding of a methyl group that is a common way for a gene to be turned off in a DNA sequence so taht it’s not expressed in the genotype.

Question 18

epigenetics is…

Answer 18

the regulation of gene expression by factors in the internal environment such as levels of nutrition, hormones, and temperature

Question 19

Biological implications of gene expression modifications

Answer 19

1. unexpected results from the effects on the expression of other genes that may be harmful or benefitial
2. effects on biodiversity from the presence of these organisms in natural ecosystems

Question 20

Selective breeding biological implications

Answer 20

1. inbreeding with closely related individuals causing inbreeding depression and genetic disorders (reduced by outbreeding that can cause hybrid vigour)
2. reduction in genetic diversity
3. selectively bred organisms (IF RELEASED) may outcompete wild types and reduce biodiversity of ecosystems
4. Selectively bred organisms have evolution controlled by humans, not natrual selection
5. Selectively bred organisms are healthier and live longer

Question 21

Transgenesis biological implications

Answer 21

1. risk of horizontal gene transfer from transgenic organisms into organisms in natural ecosystems that can affect composition and biodiversity
2. Transgenetic organisms may outcompete the wild types if released in to natural ecosystems

Question 22

cloning (whole organisms) biological implications

Answer 22

1. cloning produced individuals that are genetically identical and thus have little genetic diversity, and thus as greater risk of extinction
2. any genetic disorders within the genome of the parent will be present in offspring