Question

​Molecular Evidence
The DNA of whales is very similar to the DNA of hoofed
mammals. Below are some DNA fragments of a gene that
makes a type of milk protein.​​Hippopotamus TCC TGGCA GTCCA GTGGT
Humpback whale CCC TGGCA GTGCA GTGCT​
Identify Circle the pairs of nitrogen bases (G, T,
C, or A) that differ between the hippopotamus and
humpback whale DNA.

Answer 1

To identify the pairs of nitrogen bases that differ between the hippopotamus and humpback whale DNA, we will compare the given sequences side by side.

**Hippopotamus:**
TCC TGGCA GTCCA GTGGT

**Humpback whale:**
CCC TGGCA GTGCA GTGCT

Now, we will compare each corresponding segment:

1. TCC (hippopotamus) vs. CCC (humpback whale): **Different** (T vs. C)
2. TGGCA (hippopotamus) vs. TGGCA (humpback whale): **Same**
3. GTCCA (hippopotamus) vs. GTGCA (humpback whale): **Different** (C vs. G)
4. GTGGT (hippopotamus) vs. GTGCT (humpback whale): **Different** (G vs. C)

The pairs of nitrogen bases that differ between the two sequences are:

1. Position 1: T (hippo) vs. C (whale) in the first fragment.
2. Position 3: C (hippo) vs. G (whale) in the third fragment.
3. Position 4: G (hippo) vs. C (whale) in the fourth fragment.

So, the different pairs are:

1. (T, C)
2. (C, G)
3. (G, C)

These differences highlight the genetic variation in the two species.