TCOGE: Differences in DNA between individuals of the same species can be exploited for identification and diagnosis of heritable conditions

Question 1

What is a DNA probe?

Answer 1

A short, single stranded piece of DNA with bases that are complementary to a specific gene sequence.

Question 2

When a DNA probe attaches to a complementary gene sequence, we call this process _______.

Answer 2

DNA hybridisation

Question 3

What is DNA hybridisation?

Answer 3

When a DNA probe attaches to a complementary gene sequence.

Question 4

What are DNA probed made from?

Answer 4

DNA fragments

Question 5

What are the two ways used to label a DNA probe?

Answer 5

• Radioactively
• Fluorescently

Question 6

Both labelling methods allow scientists to identify whether a DNA probe has _______ to its complementary DNA sequence

Answer 6

annealed

(binded)

Question 7

When using a radioactive method to label a DNA probe, what part of the DNA becomes radioactive.

Answer 7

The phosphorous within the sugar-phosphate backbone

Question 8

When using a fluorescent method to label a DNA probe, what substance is used?

Answer 8

Fluorescent dye

Question 9

A radioactively labelled probe can be detected using a special _______.

Answer 9

Scanner

Question 10

A fluorescently labelled probe can be detected using a special ______.

Answer 10

Light

Question 11

Explain the process of DNA hybridisation:

Answer 11

1) Multiply DNA probe via PCR
2) Heat the DNA- this causes hydrogen bonds between nucleotides to break and the 2 DNA strands to seperate- the DNA is denatured
3) Add the DNA