Patterns Of Inheritence

Question 1

What is a phenotype?

Answer 1

Visible characteristics of an organism

Question 2

What is a genotype?

Answer 2

The genetic makeup of an organism

Question 3

What are the different types of chromosome mutations?

Answer 3

Deletion 
Inversion 
Translocation 
Duplication 
Non- disjunction

Question 4

What does deletion involve?

Answer 4

Part of a chromosome, containing genetic material is lost.

Question 5

What does inversion involve?

Answer 5

A section of chromosome breaks of. Turns 180 degrees and joins again. Some genes are too far from the regulatory sequence to be expressed.

Question 6

What does translocation involve?

Answer 6

A section of a chromosome breaks off and joins another chromosome.

Question 7

What does duplication involve?

Answer 7

A piece of chromosome may be duplicated- overexpression

Question 8

Why is overexpression bad?

Answer 8

Too many of certain l proteins or gene regulating nucleic acids may disrupt metabolism

Question 9

What does non- disjunction involve?

Answer 9

A pair of chromosomes fail to separate, leaving one gamete with an extra chromosome- e.g. Down syndrome

Question 10

What is a genotype?

Answer 10

The genetic makeup of an organism

Question 11

What is a phenotype?

Answer 11

The visible characteristic of an organism

Question 12

Heterozygous?

Answer 12

Having different alleles on a gene locus on a pair of homologous chromosomes

Question 13

Homozygous?

Answer 13

Having identical alleles on a gene locus on a pair of homologous chromosomes

Question 14

Monogenic?

Answer 14

Determined by a single gene

Question 15

Why is dihybrid?

Answer 15

Involving two gene loci

Question 16

Sex linked?

Answer 16

Gene present on the sex chromosome

Question 17

What is codominant?

Answer 17

Where both alleles present in the genotype of a heterozygous individual contribute to the individual’s phonotype

Question 18

What is autosomal linkage?

Answer 18

Gene lock present on the same autosome (non-sex) that are inherited together

Question 19

What is epistasis?

Answer 19

Interaction of non-linked loci where once masks the expression of another

Question 20

Directional selection?

Answer 20

A type of natural selection that occurs when an environmental change favours an new phenotype which results in a change in the average population

Question 21

What is the founder effect?

Answer 21

A small sample of an original population establishes in a new area, its gene pool is. It as diverse as that of the parent population

Question 22

What is a genetic bottleneck?

Answer 22

A sharp decline in population size due to environmental catastrophes. This reduces the genetic diversity.

Question 23

What is stabilising selection?

Answer 23

Natural selected leading to constancy in a population. Intermediate phenotypes are favoured and extreme phenotypes selected against. Reduces genetic variation.

Question 24

What is a population?

Answer 24

Members of a species, living in the same place at the same time. Can interbreed.

Question 25

Allopatric speciation?

Answer 25

Formation of 2 different species from one original species due to geographical isolation.

Question 26

Sympatric speciation?

Answer 26

Formation of 2 species due to reproductive isolation

Question 27

Artificial selection?

Answer 27

Selective breeding of organisms involves humans choosing the desired phenotypes and interbreeding those phenotypes

Question 28

DNA sequencing?

Answer 28

A technique that allows genes to be isolated and read

Question 29

DNA ligase?

Answer 29

Enzymes that catalyses the joining of sugar and phosphate groups within DNA

Question 30

Germ line therapy?

Answer 30

Gene therapy by inserting functional alleles into gametes or zygotes

Question 31

Somatic cell gene therapy?

Answer 31

Gene therapy by inserting functional alleles into body cells