Unit 3

Question 1

What is bioinformatics?

Answer 1

Information technology applied to the management and analysis of biological data

Question 2

What was the Earth bio genome project and what was it used for?

Answer 2

The sequencing of 1.5 million genes
used for:
new drugs, new food sources, saving species from extinction, understanding a species’ origin

Question 3

What is comparative genomics?

Answer 3

alignment with a sequence of known function based on evolutionary theory

Question 4

What is Comparative Genomics used for?

Answer 4

Association studies to find disease genes
RNA studies to investigate gene expression
Looking for single nucleotide polymorphisms

Question 5

What is the Principle of Segregation?

Answer 5

for any particular trait, during gamete formation the two alleles in each parent seperate and only one allele is passed to the offspring.
e.g. pea colour

Question 6

What is the principle of Independent Assortment?

Answer 6

when two or more genes are at the same loci, alleles for each gene are passed to the offspring independently of each other.
e.g. pear colour and shape

Question 7

What is a wildtype allele?

Answer 7

an unaltered gene

Question 8

What are the three types of group alleles in a population?

Answer 8

Loss of function alleles
Gain of function alleles
Isoalleles

Question 9

What is an Isoallele?

Answer 9

does not alter quantity or distribution- same action as wildtype allele.

Question 10

Which group allele causes reduced activity and is recessive to wildtype alleles?

Answer 10

Loss of function allele

Question 11

Which modes of inheritance have the gene on the autosome? What does this mean?

Answer 11

Autosomal dominant
Autosomal Recessive
Sex-limited inheritance

Usually means it affects males and females equally- exception of Sex-limited inheritance.

Question 12

What is the difference between Autosomal Dominant and Autosomal Recessive?

Answer 12

Dominant- one copy of mutated allele needed for disease, affected offspring have one affected parent, doesn’t skip generations
Recessive- two copies of mutated allele required for disease, can skip generations, 3/4 of offspring with two affected parents are carriers/ affected.

Question 13

Which mode of inheritance is the gene on the X-chromosome? What does this mean?

Answer 13

X-linked recessive- usually males are affected and females are carriers.

Question 14

_____________ usually appears in sex specific tissues/ organs

Answer 14

Sex- limited inheritance

Question 15

What are Polygenic traits?

Give an example

Answer 15

expression is affected by genotype and the environment e.g. Hip Dysplasia

Question 16

What are the two types of Mutations? Briefly describe them.

Answer 16

Point mutations- altered nucleotide sequence of a gene during replication e.g. substitutions, insertions
Chromosome mutations- alterations of a chromosome number

Question 17

What is Chromosome non-disjunction?

Answer 17

where chromosomes don’t seperate during cell division- so one daughter cell has an extra chromosome and the other is missing one.

Question 18

when a base change alters a codon but the new codon codes for the same amino acid this is known as a ___________

Answer 18

silent mutation

Question 19

What is a splice site?

Answer 19

when a base change at splice acceptor disrupts mRNA processing leading to incorporation of an intron.

Question 20

If a base is inserted/ deleted and not in a multiple of three, this leads to ……

Answer 20

a frameshift mutation, changing the reading frame completely and leading to premature termination