DNA Mutations

Define Mutation

A change in DNA

What are Somatic Cells___

body cells that are not passed on

What is the germ line___

gametes ( egg;sperm)

Base Pair Substitution Mutation is a type of _______

Point Mutation

Define Base Pair Substitution Mutation

A substitution where there is a exchange between two bases ( such as T and C). This substitution could change the codon that creates the amino acid and different protein could be produced.

When substitution of bases do not change the protein structure is called___

Silent Mutation

Base Pair Substitution Mutation is called a __

Mis-sense Mutation because a single nucleotide change results in a codon that codes for a different amino acid.

If the code changes to a stop codon the result is__

no protein is made

Define Nonsense Mutation

Nonsense mutation is a point mutation in DNA that results in a stop codon transcribed into the mRNA and a nonfunction protein is produced.

Define Loss-of-function Mutations

When either transcription is stopped or transcription and translation occurs but no protein is made.

This is a recessive trait.

Define Gain-of-Function Mutations

A mutation that creates a new or enhanced activity on a protein.

Define Condition Mutations

Genes that are expressed under permissive conditions

Define Frame-shift Mutation

DNA is divided into codons that are 3 bases long, when insertions and deletions occur in the codons it can change the gene completely and it's message cannot be decoded properly.

An example of Frame-Shift Mutation

she may not get to fat

-"s" is deleted

hem ayn otg ett ofa t

-"a" is added

ash ema gno tge ttte ofa t

***These are severe mutations.

Frame-Shift Mutation is the__

addition or deletion of nucleotide

Chromosomal Mutation can be___

Polyplordy or anueplody

Define Autopolyploidy

Having more than the normal number if diploids or less

Define Polyploidy

a normal diploid cell acquires one or more sets of chromosomes

Define Deletions

is when parts of genetic code is lost or deleted

-This could lead to servere disorders or even fatality

Define Duplication Mutation

When a portion of the genetic code or a chromosome is duplicated and replication resulting in multiple copies.

(Chromosomal Mutation)

Define Homologous Chromosomes

The same chromosome number that are similar in size, shape, number and type of gene

(Chromosomal Mutation)

Define Inversion Mutation

If two breaks occur in one chromosome, sometimes the region between the breaks rotates 180 degrees before rejoining with the two end fragments.

(Chromosomal Mutation)

Define Translocation Mutation

one segment of a chromosome moves to another chromosome

-results in infertility(cant get pregnant)

(Chromosomal Mutation)

Define Cancer

-uncontrolled cell division

-fast growing cells

Mutagens can be__

physical or chemical

Chemical Mutagens___

react with DNA causing a change

- can be caused by smoking, plastics, food

Physical Mutagens__

change the structure of DNA

Define Carcinogens

cancer causing mutations

Cancer Cells lose contact with__

inhibition property to grow in size

-results in tumors

Oncogenes are__

cancer causing cells

Define Mestastasize

the spread of cancer cells in the body by metastasis

The purpose of the regulator gene (repressor gene) is too__

turn off the onco gene

Carcinogens breaks the DNA and the repressor gene becomes___

too far to the onco gene to turn it off and the onco gene is activated