Module 6A Flashcards
Neoplasm
Tumour caused by uncontrollable abnormal cell division
What are the three types of neoplasms
Benign, potentially malignant, malignant
Mutagen
An agent that causes genetic mutation
Proto-oncogene
Normal genes involved in the regulation of cell division, which stimulate the growth and development of cells.
Oncogene
A mutation of the proto-oncogenes which induce uncontrollable cell division, leading to the development of neoplasms
Apoptosis
Programmed cell death
Mutations
Any changes that occur to the sequences of the nucleotide bases of DNA by exposure to mutagens
Point mutation
Forms of alterations done to one or various DNA bases
Chromosomal mutation
Alterations that affect whole chromosomes and genes, rather than individual nucleotides
Carcinogens
Chemical or physical agents able to cause cancer in the body
What are the three kinds of point mutations?
Substitution: When a mutation changes one base of a gene, and changes the structure of the amino acid
Deletion: When a base is deleted or removed and changes the order of all the codons
Insertion/Frameshift: When a base is inserted into the gene sequence and changes the order of all the codons
For a mutation to introduce a new allele into the population it should:
- Occur in a coding region of DNA
- Occur in a gamete (germ-line)
- Alter the sequence of amino acids of a polypeptide
- Alter the phenotype associated with a protein
What happens to a mutation in a non-coding region?
Mutations in noncoding regions often do not impact proteins.
What are some examples of non-coding regions in DNA?
Regulatory regions, introns and promoters (eg TATA box, which indicates where transcription begins)
What happens if a mutation occurs in a coding area?
Mutations are more likely to impact the correct formation of proteins, as genes in this DNA encode for proteins
