Question

22) Research using model organisms provides important insights into our understanding of human diseases. What are some of the specific ways in which model organism research contributes to our understanding of and treatments for human diseases?
A) Drugs targeting proteins implicated in human diseases can be screened for effectiveness in certain model organisms
B) Model organisms research can promote discovery of new genes involved in human diseases
C) Model organism research can be used to develop research methods or technologies that support research into human diseases
D) All of these statements are true
E) Only two of these statements about model organism research are true

23) The ______ kinase is essential in yeast for adding an inhibitory phosphate group to ______ when it is bound to a cyclin, which prevents the cell from entering mitosis until all conditions of the checkpoint are cleared and the phosphate group is removed
A) cdc25; cdc2 kinase
B) weel; cdc2 kinase
C) cdc25; MPF
D) MPF; cdc1 kinase
E) p21; cdk 2

33. you start a new job as a research assistant and are asked to decide on a new model organism to study a human disease. You start by writing a list of valuable characteristics for model organisms. Which of the following are advantages of performing research on model organism?  
a. Research on model organisms often require more sophisticated equipment and is more expensive than working with human cells
b. Model organisms are simpler to work with because they donot have genes that are conserved with (or similar to) human genes.
c. There are not many tools available for genetic manipulation of model organisms
d. The genomes of model organisms are often less complex than human genomes
s. None of the above are advantages of working with model organisms

Answer 1

Ans 22. D all of the abobe are true

• The use of metrazol (pentylenetetrazol) as an animal model of epilepsy
• Induction of mechanical brain injury as an animal model of post-traumatic epilepsy
• Injection of the neurotoxin 6-hydroxydopamine to dopaminergic parts of the basal ganglia as an animal model of Parkinson's disease.
• Immunisation with an auto-antigen to induce an immune response to model autoimmune diseases such as Experimental autoimmune encephalomyelitis
• Injecting animals with agonists or antagonists of various neurotransmitters to reproduce human mental disorders
• Implanting animals with tumors to test and develop treatments using ionizing radiation

Ans 23. B. Wee1 and cdc2 kinase

Cdc2 targets many cellular proteins involved in mitosis, activating them by catalytically adding phosphate residues to threonine and serine residues. In this second biological role, the Cdc2/Cyclin heterodimer is termed the mitosis promoting factor, or MPF.Wee1 is a nuclear kinase belonging to the Ser/Thr family of protein kinases in the fission yeast Schizosaccharomyces pombe. Wee1 has a molecular mass of 96 kDa and is a key regulator of cell cycle progression. It influences cell size by inhibiting the entry into mitosis, through inhibiting Cdk1

Ans 33. d. The genomes of model organisms are often less complex than human genomes

The best models of disease are similar in etiology (mechanism of cause) and phenotype (signs and symptoms) to the human equivalent. However complex human diseases can often be better understood in a simplified system in which individual parts of the disease process are isolated and examined. For instance, behavioral analogues of anxiety or pain in laboratory animals can be used to screen and test new drugs for the treatment of these conditions in humans.