🩶 3.4 Topic 4 - 3.4.7 Investigating diversity

Question 1

What are 3 technologies that have been useful for clarifying evolutionary relationships?

Answer 1

Genome sequencing, comparing amino acid sequences and immunological comparisons.

Question 2

What does genome sequencing determine?

Answer 2

It determines the entire base sequence of an organisms DNA.

Question 3

What is the sequence of amino acids in a protein coded for by?

Answer 3

The base sequence in DNA.

Question 4

What technologies have changed the way in which genetic diversity is assessed?

Answer 4

Gene technologies.

Question 5

_ _ _ _ _ _ _ determine different characteristics.

Answer 5

Alleles.

Question 6

What does a wide variety of each characteristic in a population indicate?

Answer 6

a high number of different alleles - so a high genetic diversity.

Question 7

What do similar proteins bind to?

Answer 7

The same antibodies.

Question 8

What will different alleles of the same gene have? What will they also produce?

Answer 8

Slightly different DNA base sequences.
Slightly different mRNA base sequences and may produce proteins with slightly different amino acid sequences.

Question 9

What does comparing the DNA base sequences of the same gene in different organisms in a population allow scientists to find out?

Answer 9

How many alleles of that gene there are in that population.

Question 10

As different alleles will also produce slightly different mRNA base sequences, what does this mean?

Answer 10

That they may produce proteins with slightly different amino acid sequences, sp these can also be compared.

Question 11

What is variation?

Answer 11

The differences that exists between individuals. There is variation between species and within species.

Question 12

What are two types of factors which cause variation within a species?

Answer 12

Genetic factors and environmental factors.

Question 13

How can genetic factors cause variation within a species?

Answer 13

Different species have different genes, which causes variation between species.
Individuals of the same species have the same genes, but different alleles causing variation.

Question 14

What are examples of environmental factors which cause variation within a species?

Answer 14

Climate, food and lifestyle.

Question 15

What do you have to sample to study variation?

Answer 15

A population.

Question 16

As same data will be used to draw conclusions about the whole population, the sample has to be random, why?

Answer 16

So that it accurately represents the whole population and that any patterns observed are tested to make sure they are not due to chance.

Question 17

You can use the _ _ _ _ to look for variation between samples.

Answer 17

Mean.

Question 18

What is the mean?

Answer 18

The mean is an average of the values collected in a sample.

Question 19

What is the formula you use to find the mean?

Answer 19

Total of all the values in your data/the number of values in your data.

Question 20

What distribution does a bell-shaped graph show? why?

Answer 20

A normal distribution - this is because most samples will include values either side of the mean.

Question 21

A normal distribution is _ _ _ _ _ _ _ _ _ _ _ about the mean.

Answer 21

Symmetrical.

Question 22

What does standard deviation tell you about?

Answer 22

It tells you how much the values in a single sample vary.

Question 23

Standard deviation is a measure of what?

Answer 23

The spread of values about the mean.

Question 24

What does a large standard deviation mean?

Answer 24

That the values in the sample vary a lot.

Question 25

What does a small standard deviation mean?

Answer 25

That most of the sample data is around the mean value, so only varies a little.

Question 26

What does a graph which is steep tell you about the standard deviation?

Answer 26

That the values are similar and close to the mean so therefore the SD is small.

Question 27

What does a graph which is wide tell you about the standard deviation?

Answer 27

That the values vary a lot so therefore the SD is large.

Question 28

What bars can you draw with standard deviation?

Answer 28

Error bars.

Question 29

What do error bars do with standard deviations?

Answer 29

Error bars extend one SD above and one SD below the mean. This means that the total length of the error bar is twice the SD.

Question 30

On an error bar what does the longer the bar mean?

Answer 30

Means the larger the SD is and the more spread out the sample data is from the mean.

Question 32

Early estimates of genetic diversity were made by looking at …

Answer 32

… the frequency of measurable or observable characteristics in a population.

Question 33

What do alleles determine?

Answer 33

Different characteristics.

Question 34

A wide variety of each characteristic in a population indicates …

Answer 34

… a high number of different alleles - a high genetic diversity.

Question 35

What gene technologies have now been developed that allow us to measure genetic diversity directly?

Answer 35

• Different alleles of the same gene will have slightly different DNA base sequences. Comparing the DNA base sequences of the same gene in different organisms in a population allows scientists to find out how many alleles of that gene there are in that population.
• Different alleles will also produce slightly different mRNA base sequences, and may produce proteins with slightly different amino acid sequences, so these can also be compared.

Question 36

What can new technologies be used to give and compare?

Answer 36

• More accurate estimates of genetic diversity within a population or species.
• The genetic diversity of different species to be compared more easily.