Question 1

Why are mice preferred as model organisms in research?

Accepted Answer

Mice are ideal research subjects because they reproduce quickly and produce large offspring numbers, enabling rapid colony generation. Their small size requires minimal housing space, and they share striking genetic similarity to humans. Additionally, mice are inexpensive to maintain, making them economical for large-scale scientific investigations.

Question 2

What is a knockout mouse and how is it created?

Accepted Answer

A knockout mouse is genetically modified to replace a segment encoding specific genes with selectable markers, effectively disabling that gene. This modification allows researchers to assess the physiological requirement for individual gene products. For example, knockout mice have been used to measure changes in embryonic heart rate caused by the absence of specific enzymes.

Question 3

What makes inbred mouse strains valuable for experiments?

Accepted Answer

Inbred mouse strains possess genetic uniformity, which eliminates variables introduced by genetic diversity among individual mice. This uniformity significantly improves experimental reproducibility and consistency. Many families of inbred strains exist, such as the C57BL/6J line, which remains commonly used in research labs today.

Question 4

How do nude mice differ from standard laboratory mice?

Accepted Answer

Nude mice have a genetic makeup that results in missing hair and a severely compromised immune system. These characteristics make them superior hosts for in vivo experiments involving foreign tissue introduction, such as monitoring engraftment of cancer cells. Their immunodeficiency prevents rejection of transplanted tissues.

Question 5

What is the Morris water maze and what does it measure?

Accepted Answer

The Morris water maze is a behavioral test that measures spatial memory in mice. In this paradigm, mice are trained to use visual cues to locate a platform and escape from a pool of water. The test assesses how the brain records and recalls memories, making it valuable for studying cognitive function and learning.

Question 6

How quickly do mice reach sexual maturity and reproduce?

Accepted Answer

Mice have a remarkably short life cycle compared to other mammals. Gestation lasts only 18 to 21 days, after which pups are born hairless and blind. Pups develop into sexually mature adults by just 8 weeks of age, enabling rapid generation of experimental colonies for research purposes.

Question 7

What types of disease research can be conducted using mice?

Accepted Answer

Mice serve as excellent models for studying infectious diseases because their immune systems function similarly to humans. Researchers use mice to investigate food-borne pathogens like Listeria and viral diseases such as herpes virus by mimicking physiological exposure routes. Understanding mouse development and disease progression also improves knowledge of human development and disease mechanisms.

מבוא לעכבר המעבדה: שרירים - חידון הערכה