1.7.1 Evidence for Evolution: Biochemical Similarities

Question 1

review

Answer 1

• DNA makes proteins.
• Proteins are molecules made from long chains of amino acids.
• The arrangement of amino acids in a protein determines what that protein will be.

Question 2

note

Answer 2

• Biochemical similarities between different species back up the fossil record as evidence for evolution
• Similarities between proteins and DNA can be used to trace ancestry between species.

Question 3

how much DNA is used to make proteins

Answer 3

• 2%

Question 4

DNA

Answer 4

• Human and chimp DNA is 98.3% similar.

- Human and gorilla DNA is 98.2% similar.

Question 5

Similarities between species of the structural composition of which of these classes of macromolecules would be best to use in indirectly determining the degree of homology of the DNA between species?

Answer 5

• proteins

Question 6

hemoglobin

Answer 6

• a protein molecule with four sub-units found in red blood cells
• carries oxygen in the cells

Question 7

Based on DNA evidence, which species are more closely related?

Answer 7

• humans and chimpanzees

Question 8

Which of the following is not true of comparisons between the DNA and/or proteins of species?

Answer 8

• They can help us determine what future evolutionary adaptions will be

Question 9

When comparing hemoglobin across species, frogs have 67 amino acids which differ from humans. Mice differ by only 27 amino acids. The evolutionary implications are that

Answer 9

• Humans and mice share a more recent common ancestry than humans and frogs

Question 10

Most biologists support the theory that species evolve because

Answer 10

• studies at many levels of biological organization have provided evidence that the theory is not wrong.
• there has been no theory postulated that better explains the biological record.