Model organisms for research

Question 1

Name the 4 important characteristics of genetic model organisms and explain its meaning

Answer 1

1. Simplicity: Model organisms often have a simple and well understood biology, making them easier to study than more complex organisms. The simplicity makes it easier for researchers to manipilate genes
2. Genetic toolbox available: many model organisms have well developed genetic toolbox such as the ability to produce transgenic animals or plants
3. Genetic conservation: The genomes of different species are often highly observed, meaning that many similar genes are present in different species
4. Versatile: Model organisms are chosen for their versatility and suitability for specific research questions

Question 2

What is the difference between geno- and phenotype

Answer 2

Genotype: complete set of an individuals gene (inherited) which carry the genetic info that determines an organisms phenotype and behaviour traits

Phenotype: the obserable physical/behaviour traits of an organisms, which result from the interaction between its genotype and the environment. It needs to be qualitativaley/quantitatively measurable.

Question 3

What are the 2 different mutations

Answer 3

1. Loss of function mutation: inactivating mutation
2. Gain of function mutation: activating mutation

Question 4

What is Reverse Genetics

Answer 4

The process of identifying gene responsible for a particular phenotype by manipulating the genome and observing the effect on the phenotype. You are aware of which specific gene to manipulate, so this is a biased technique

Question 5

What are the 3 forms of Reverse Genetics?

Answer 5

• Knock-out (At DNA level); affect all generations
• Knock- down (At RNA level); affect non-maybe 2 generations
• Protein degration (At protein level)

Question 6

What is Forward Genetics?

Answer 6

The approach of identifying the phenotype (observable traits) of an organism and then working backwards to determine the genetic basis of that phenotype. This approach involves generating RANDOM (so unbiased) genetic mutations (radiation)

Question 7

What is a transgenic animal?

Answer 7

Genetically modified animal

Question 8

Name some of the main characteristics of using Yeast as a model organism for research

Answer 8

1. Fast growth rate
2. Easily manipulated genetically
3. Similarity to higher eukaryotes (although it’s unicellular)
4. Accessibility to microscope

Question 9

Name some of the main characteristics of using the fruitfly (Drosophila) as a model organism for research

Answer 9

1. Short generation time
   2, Large number of offspring
2. Easy to culture
3. Well studied genome
4. Simple, but complex

Question 10

Name some of the main characteristics of using the zebrafish (Danio rerio) as a model organism for research

Answer 10

1. It’s a vertebrate
2. It has a circulatory system
3. Regeneration (can regenerate some part of their body)
4. They have a well developed immune system

Question 11

Name some of the main characteristics of using the mouse as a model organism for research

Answer 11

1. Strong homology with human genome
2. Relatively short life span compared to humans
3. Possible to manipulate their genome (knock-out mice)