Question

1. The human genome is composed of approximately how many base pairs?
2. What is the complementary DNA sequence to GATC?
3. There are 3 subunits to DNA: nitrogenous base, sugar and phosphate group. What do
the sugar and phosphate contribute to DNA?
4. How many DNA bases are there in one codon?
5. If codons consisted of 2 bases instead of 3 and everything else was the same (DNA
consisted of 4 different bases, ATGC), what is the maximum number of amino acids that
could be specified (coded for)?
6. Why are there 3 bases per codon?
7. Errors sometimes occur when DNA duplicates itself. Why is this essential to evolution?
8. Which statement about mutations is true?
9. Using the first row as the reference, what kind of mutation occurred to generate the
sequence in the 2nd row?

A T G T G G C A T A A T G G C A C A...
A T G T G G C A T A T G G C A C A T...
10. Which of the following does NOT cause mutations?
11. The International Agency for Research on Cancer has classified ______ as a carcinogen.
(Its use before the age of 30 increases melanoma risk by 75%).
12. The trait ‘dollop’ is caused by a recessive gene (d). If the frequency of d is 0.3 in a
population, what is the expected frequency of dollop?

13. The longer two species have been evolving independently (since a common ancestor), the
greater the number of mutations that accumulate between them. In fact, the rate of change is
_______. This allows us to compare sequences from different individuals or species
and estimate the years since they had a common ancestor.
14. Which group is most distantly related to tuna (the longest time since they had a shared
ancestor)?

15. The fact that fish, penguins (birds), and dolphins (mammals) all have the same basic
shape (torpedo-like) is best explained by which of the following?
16. Which of the following is a statement that describes the concept of convergent evolution?
17. Anatomical similarities, like the number and structure of bones, among vertebrate forelimbs
suggests that all vertebrates evolved from a common ancestor. Possession of a trait in two or
more species derived from their common ancestor is known as?
18. Which of the following is NOT an example of a vestigial trait?
19. Where would I most likely find the oldest fossils in sedimentary rock?
20. The close relationship between fossil and extant (living) species from the same geographical
area, or between fossils within adjacent rock strata, is one of the oldest types of evidence for
evolution. It is called _____.

21. You are given a fossilized piece of wood by someone who tells you that it is has been
carbon-dated to ~20,000 years ago. Approximately how much of the original carbon-14
remains? Use 5,000 years as the half-life for carbon-14 to make the math easier.
22. Which of the following is true of lactose tolerance in adult humans?
23. How does natural selection cause evolution?
24. How do bacteria become antibiotic resistant?
25. Human birth weight is a classic example of:
26. Imagine that those who had children at a younger than average age tended to leave more
descendants than others. This continued to be true over hundreds of generations across the
planet. What else would evolve as a consequence?
27. Which is definitely an INCORRECT explanation for why we grow old?
28. Why is adaptation imperfect?
29. Anatomical similarities, like the number and structure of bones, among vertebrate
forelimbs suggests that all vertebrates evolved from a common ancestor.
30. Which are true of cancer cells?

Answer 1

1) the human genome is complex and resides in the 23 pairs of chromosomes. The number of base pairs present is approximately 3 billion.

2) In DNA base pairing, complementary bases pair with each other. Guanine(G) pairs with cytosine(C) and Adenine(A) pairs with thymine(T).

The given sequence is- GATC. Based on the above information, the complementary sequence will be ---- CTAG.

3) The basic structural subunits of DNA are nucleotides. They are composed of nitrogenous bases( A, G, T, C), Sugar and phosphate. This sugar and phosphate together forms the backbone of the DNA molecule.

4) Codons are code words that are required for protein synthesis. Codons are composed of the bases adenine, guanine, cytosine and uracil. Each codon consists of 3 bases. For example, AUG (Adenine, uracil and guanine) is a start codon that codes for the amino acid methionine.