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Flashcards in Determining Relatedness Between Species Deck (13):
1

What is DNA sequencing?

Determining the exact order of nucleotides in a section of DNA

2

How is DNA sequencing used to determine relatedness between species?

Sections from 2 organisms similar genes are sequenced and compared, with a number of differences indicative of how related the 2 are.

3

Why are organisms Mitochondria useful in determining relatedness?

Mitochondria contain their own circular DNA which mutates at a known rate. Only mothers can pass down their mitochondria.

4

How does the molecular clock work?

As we know the rate at which mitochondrial DNA mutates if we compare 2 organisms mitochondrial DNA the amount of differences/mutations that have accumulated will tell us how long ago the 2 species diverged from one another

5

How does DNA hybridization determine relatedness between species?

2 samples of DNA are denatured and then mixed and combined together to form a single strand. The strands are then re heated and the temperature at which they denature indicates how many similarities there are in each strands base sequence

6

What does a high Tm mean?

stronger bonds = less difference between strands = more related

7

What does a low Tm mean?

Weaker bonds = more difference between strands = less related

8

What difference in melting temperature corresponds to a one per cent difference in DNA sequence?

1-degree Celsius

9

What temperature is DNA heated to so the strands separate in DNA hybridization?

87 degrees Celsius

10

What bonds hold together DNA?

Hydrogen bonds

11

What does a phylogenetic tree show?

The evolutionary relatedness between species

12

What is the protein that's level of production affects the Galapagos finches beak formation?

BMP4

13

What techniques can be used to make a phylogenetic tree?

Molecular techniques such as DNA sequencing, molecular clocks and hybridisation