BIO - MOD 6

what is a mutagen?

any physical, chemical, or biological agent that can cause changes (mutations) to the DNA sequence in an organism’s genome.

what are the two types of mutagens?

radiation (physical) or chemical mutagens

what are the two types of mutations?

point mutation or chromosomal mutation

what is a point mutation?

mutations involving single genes

what are the three types of point mutations?

base substitutions, insertions and deletions

which point mutations cause a framshift mutation?

base insertions & deletions

what is a frameshift mutation?

where the reading frame position for all bases is altered which significantly changes the amino acid sequence & results in a non-functional protein.

what are the types of base substitutions (point mutations)?

silent, missense & nonsense

what is an example of a point mutation?

sick cell anaemia

what is a chromosomal mutation?

changes to the number or structure of entire chromosomes

what are the two ways chromosomal mutations can be expressed?

numerical (changes to number of chromosomes) OR structural (changes to structure of chromosomes)

what is polypoidy (numerical chromosomal mutation)?

entire genome duplication

what is deletion (numerical chromosomal mutation)?

missing chromosome

what is aneuploidy?

having an abnormal number of chromosomes in a cell (trisomy or monosomy)

what is an example of a chromosomal mutation?

down syndrome (trisomy 21)

what are the types of structural chromosome changes?

deletion, duplication, inversion & translocation

what is a somatic mutation?

any mutation that only affects body cells

what is an example of a somatic cell mutation?

cancer

what is a germ-line mutation?

where a mutation from parent cells, are inherited and is part of DNA is ech cell of offspring

what are some examples of germ-line mutations?

colour blindness & cystic fibrosis

what is a mutation in coding DNA?

mutation which has a direct impact on how protein works

what is a mutation in non-coding DNA?

mutations which impact gene regulation rather than the protein itself

what are three causes of genetic variation?

mutations, meiosis and fertilisation

how do mutations cause genetic variation?

create new alleles which can be passed to offspring & are essential for evolution

how does meiosis cause genetic variation?

independent assortment, crossing over, & random segregation create possible gene combinations, increasing variation

how does fertilisation cause genetic variation?

combines gametes from two parents, causing existing alleles to produce genetically unique offspring (NOT NEW ALLELES)

what is a gene pool?

the combined genes of a population, including the different alleles for each gene

how can mutations impact gene pools?

create new versions of genes, which adds new alleles to the gene pool & more alleles = greater diversity in the population

how can gene flow impact gene pools?

new individuals in population = new alleles = diversity in gene pool

what is gene flow?

changes in allele frequency due to new individuals entering a population or from individuals exiting a population

what is genetic drift?

changes in allele frequency in the gene pool of a population due to random chance

how can genetic drift impact gene pools?

alleles may be lost completely by chance = shrinking the gene pool & reducing diversity

what is the bottleneck effect? (genetic drift)

when a large population is drastically reduced by disaster

what is the founder effect? (genetic drift)

when individuals isolate themselves to start a new population

what is biotechnology?

manipulation of living organisms and/or their parts to develop new products or processes intended to improve human health and society

what is an example of a past biotechnology?

selective breeding

what is selective breeding?

choosing particular organisms from which to breed because they have certain desirable characteristics

what are some examples of present biotechnologies?

• Transgenic/Genetically Modified Organisms (GMO’s)

• Recombinant DNA

• Stem-cell tehrapy

• Gene therapy

what is an example of furture biotechnologies?

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)

what do GMO’s involve?

an organism or cell whose genome has been altered by the introduction of one or more foreign DNA sequences from another species by artificial means

what does CRISPR allow?

allow to selectively modify DNA in a living organism

what are three societal concerns of biotechnology?

harm to the environment, bioterrorism & lab/production safety

what is ethics?

why certain decisions are understood to be morally wrong, and the reasoned views behind making these judgements

what are some benefits of genetic technologies?

• improvements to human health

• higher production & quality of food

• production of useful materials

• safer water supplies

what is the overall impact of genetic technologies on biodiversity?

decreased biodiversity

what does recombinant DNA involve?

inserting/modifying an organism’s genes, with genes from another species, to create a transgenic organism (new genetic combination)

what is artificial insemination?

assisted placement of sperm into the female reproductive tract in animals

what is artificial pollination?

assisted transfer of pollen from the male part of a flower to the female part of the flower in plants

what are some common advantages of biotechnologies?

higher profits (lower costs), better quality products, improved quality of life & more efficiency in production

what are some common disadvantages of biotechnologies?

welfare of animals/testing subjects, reduction of genetic diversity, inequitable access & ethical/confidentiality concerns

what are the two types of cloning?

whole organism & gene cloning

what does PCR stand for?

polymerase chain reaction

what is the purpose of PCR?

to make copies of DNA using the enzyme polymerase, primers & nucleotides

what are the two types of cloning completed in animals?

whole organism & embryo cloning

how is whole organism cloning completed in animals?

removing desired DNA from the animal wanting to clone, insert DNA into the donor egg which has had its’ nucleus removed & then insert into the surrogate mother

how is artificial embryo cloning in animals completed?

an egg is artificially fertilized by sperm, then cells that have completed mitosis from egg are separated, creating multiple identical embryos which are implanted into surrogate mothers

what is an enucleated egg?

an oocyte (egg cell) whose nucleus (containing its genetic material) has been removed

what cells complete meiosis?

germ cells located in the testes or ovaries to produce sperm or eggs

what cells complete mitosis?

body cells divide to create identical daughter cells for growth and repair

does embryo cloning create identical twins or identical offspring to the parent?

identical twins

what are some methods of whole organism cloning in plants?

rhizomes, runners, tubers, cuttngs & budding

what are some advantages of whole organism cloning in plants?

• no fertilization, sperm or egg, pollination, seed dispersal or sexual parts are required

• faster than sexual reproduction when conditions are favourable

what is a transgenic organism?

living organism whose genetic material has been altered by the introduction of foreign DNA from a different species through genetic engineering

what are some examples of transgenic organisms created by recombinant DNA?

bt cotton, aquadvantage salmon & insulin producing bacteria

what application does insulin producing bacteria relate to?

medical application

what application does aquadvantage salmon relate to?

industrial application

what application does bt cotton relate to?

agricultural application

what is centrifugation?

method used in biotechnology: spinning samples at high speeds to form a sedimented "pellet" at the bottom of a tube

what is lysis?

method used in biotechnology: rupturing of the cell wall

what is a micropyle?

a small opening in the egg of a fish, insect, etc., through which spermatozoa can enter

what are bioreactors?

large-scale industrial fermentation tanks, used in the production of insulin producing bacteria

what are some advantages of artificial selection?

• increased production/yield

• increased quality of products

• increased profits (through improved production)

• increased food production, to minimise shortage (through improved production)

what are some disadvantages of artificial selection?

• discomfort/welfare concerns for animals

• time consuming & effort required

• loss of genetic diversity in the long term

what is biodiversity?

the variety of all living organisms on Earth

what is an environmental biotechnology?

biotechnologies developed to address environmental issues

what is an example of environmental biotechnology? (bioremediation)

genetically engineered bacteria to metabolise harmful pollutants like plastics and oil