module 6 biology

how can chemical mutagens occur?

- chemical is INCORPORATED in DNA - chemicals are INSERTED in DNA - chemicals make GAPS in DNA

what is coding dna?

DNA which codes for the amino acid sequence of a protein.

What is non-coding DNA?

DNA which doesn't code for protiens

what does ionising radiation mean and give examples?

They carry enough energy to knock electrons off atoms examples include UV lights x-rays Gamma rays

what is a somatic mutation?

a change in DNA in a somatic cell (body cells)

what is an induced mutation?

a mutation caused by a mutagen that could be either; - chemical - biological - form of radiation that cause a change in DNA structure

distinguish between a mutation and a mutagen?

a mutation is the alteration of DNA in which the sequences of DNA has been changed. Mutagen is the an environmental agent that cause a mutation.

what is a germline mutation?

a mutation that occurs in the sexual reproductive cells (germline cells) that give rise to gametes and can be passed to every cell in the offspring

what is a non-biological mutagen give an example?

a naturally occurring mutagen in the environment that originates from non-living matter, such as metals

define in chromosomal mutations; deletions inversion duplication non-disjunction translocation

a) deletion --> section breaks of and is lost b) inversion --> section breaks of, flips and reattaches c) duplication --> section is accidently copied more than once d) non-disjunctions --> chromosomes don't properly separate e) translocation -->section breaks of and sticks to another chromosome

What is sickle cell disease?

abnormal hemoglobin: red blood cells are crescent shaped.

what is a germline cell?

any cell in that can divide (meiosis) to form sex cells

what is a somatic cell

any cell that forms the body tissue of the organism

what are naturally occurring mutagens?

are mutagenic agents that are present at normal levels within natural environments, and may cause mutations. That are seperated into 2 sub categories; 1. biological mutagens 2. non-biological mutagens.

examples of somatic cells (COMBS)

connective tissue organs muscle bones skins

what is an example of germline mutation?

down syndrome (trisomy 21)

How do point mutations occur?

due to error in DNA replication

what causes chromosomal mutation

due to errors of cell division and mostly occur during during crossing over in meiosis

what is the effect of point mutation if a nucleotide base is inserted or deleted?

every single codon after the mutation is affected and therefore the trna will not be able to group the correct codon hence the protein structure will be wrong. this is called frameshift mutation

what is an example of a non-coding DNA

lung cancer

what is an example of somatic mutation?

lung cancer is a disease that results in uncontrolled cell growth in the lungs. forming clumps which are called tumors

what are the 3 possible effects of non-coding DNA?

makes functional RNA: change in the efficiency of protein synthesis regulatory sequences: changes the amount of protein produced repetitive sequence: none

what is a mutagen?

mutagen an environmental agent that alters DNA, causing mutations

what is the difference between point mutation and chromosomal mutation in which the mutation occurs?

point mutation occurs in DNA replication chromosomal mutation occurs in cell division

what is the difference between point mutation and chromosomal mutation?

point mutation: change of one base sequence chromosomal mutation: messing with a big section of the chromosome.

Name the three types of mutagenic agents and give two examples of each.

radiation occurring mutagens - UV lights - X-rays Natural occurring mutagens - biological mutagen --> virus - non-biological mutagen --> metal --> mercury chemical mutagen - ingested --> tar from smoking - environmental --> asbestos

What does carcinogenic mean?

cancer causing

What are point mutations?

changes to a single (one) base pair of DNA and affect only a single gene

what is electromagnetic radiation?

comes from the sun and is a form of energy that is all around us, such as radio waves, microwaves and gamma rays. This energy is transmitted in waves or particles in a range of wavelengths and frequencies.

what is the wavelength and energy required for electromagnetic sources to be a mutagen.

short wavelength but high energy and high frequency

what is an example of point mutation and explain?

sickle cell disease in which the mutated code gtg changes the amino acid to GAL to VAL making hemoglobin fall into an abnormal shape. making the hemoglobin clump together resulting into a crescent shape blood cell.

which has a higher chance of a mutation occurring somatic or germline cells.

somatic cells have a

the effect of a mutation in coding DNA depends on the type of mutaiton which are?

somatic or germline cell and insertion, substitution, deletion

What is mutagenesis?

the origin and development of a mutation

What is a frameshift mutation?

when a single base is inserted or deleted in the DNA, every single codon after the mutation will be affected. (it will shift it --> refer to atomi)

what are the three ways point mutation can occur through (inserting ....etc)?

1. INSERTING a nucleotide base 2. DELETION nucleotide is not included 3. SUBSTITUTION wrong nucleotide is added.

what are the three ways substitution of a point mutation can occur?

1. mis sense 2. non-sense 3. silent

what is a biological mutagen give an example?

A mutation agent in the form of a virus or bacterium or some other living organism

What are chemical mutagens and what environment /condition does it need to be in in order for it to occur?

Chemical mutagens are chemicals that cause mutations if cells are exposed to them at high frequencies or for prolonged periods of time.

what are happens if a chemical mutagen occurs?

Chemical mutagens cause a change in DNA that alters the function of proteins and, as a result, cellular processes are impaired.

what are the five was in which chromosomal mutation occurs (DID'NT --> acronym) and define each?

DID'NT a) deletion b) inversion c) duplication d) non-disjunctions e) translocation

explain why many mutations are carcinogenic?

Mutations is an alteration of the DNA in which the nucleotides are altered. Therefore some mutations occur in genes that regulate the cell cycle and sometimes suppress or promote cell division. as a result there is an increased cell division with no differentiation. resulting in a masses of cells called tumours.

what is mis-sense mutation

POINT MUTATION substitution of one nucleotide so the codon codes for a different amino acid.

What is a silent mutation?

POINT MUTATION substitution of one nucleotide so the codon codes for the same amino acid.

What is a non-sense mutation?

POINT MUTATION substitution of one nucleotide so that the codon codes for a stop codon --> prematurely stops the growth of a polypeptide.

What is a chromosomal mutation?

in whole sections of chromosomes being deleted, inserted, inverted or translocated to other chromosomes. These

what are the two subcategories examples in which chemical mutagens can occur give examples?

ingesting chemicals --> tar in tobacco, charred and fatty food. environmental --> cleaning products, asbestos

What is a mutation?

is the change in the genetic material of a cell and as a result the sequence of the nucleotides in DNA is altered