Genetics (mutations)

Question 1

What is genetics

Answer 1

Branch of biology concerned with the study of genes, genetic variation and heredity in organisms

Question 2

Law of segregation

Answer 2

For every trait there are two factors. These discrete factors get separated during gamete formation and every gamete only gets one of the two discrete factors. They join together as the gametes fuse to form a zygote

Discrete factors= genes

Question 3

What is a gene

Answer 3

Segment of dna that codes for the synthesis of one particular protein

Question 4

What id an allele

Answer 4

Portion of a chromosome that carries a particular gene

Question 5

Mutation

Answer 5

A change in the nucleotide sequence of the genome of an organism

Question 6

What can mutations result from

Answer 6

• errors during dna replication, mitosis, meiosis
• damage to dna or the repair pathways
• insertion or deletion of segments of dna due to mobile genetic elements

Question 7

Examples of point mutations

Answer 7

Substitution: one base is incorrectly replacing the pair in the complementary strands
Insertion: one or more extra nucleotides are inserted into replicating dna
Deletion: one or more nucleotides is skipped during replication

= frmaeshift mutations

Question 8

Examples of chromosomal mutations

Answer 8

Inversion: one region of chromosome is flipped and reinserted
Deletion: region of chromosome is lost
Duplication: region of chromosome is repeated
Translocation: region of one chromosome is attached to another chromosome

Question 9

Examples of copy number variation

Answer 9

Gene amplification- number of tandem copies of a locus is increased
Expanding trinucleotide repeat= normal number of repeated trinucleotide sequences is expanded

Question 10

Example causes of mutation

Answer 10

Radiation (uv/ X-rays)
Cigarette smoke
Nitrate in hot dogs or other preserved meat
Barbecuing
HIV

Question 11

What is polymorphisms

Answer 11

Variability between individuals