Comb shapes in chickens

9/16 walnut (R- P-)

3/16 rose (R- pp)

3/16 pea (rr P-)

1/16 single (rr pp)

TLS Online TPP Program

#Id: 3247

#Unit 3. Fundamental Processes

Mutations are also caused by compounds that substitute for normal bases (base analogs) or slip between the bases (intercalating agents) to cause errors in replication. 

TLS Online TPP Program

#Id: 3248

#Unit 3. Fundamental Processes

One of the most mutagenic base analogs is 5-bromouracil, an analog of thymine.

TLS Online TPP Program

#Id: 3249

#Unit 3. Fundamental Processes

The presence of the bromo substituent allows the base to mispair with guanine via the enol tautomer

TLS Online TPP Program

#Id: 3251

#Unit 3. Fundamental Processes

5-bromouracil induces transitions in both directions, A:T ↔ G:C.

TLS Online TPP Program

#Id: 3254

#Unit 3. Fundamental Processes

Tautomeric forms of the four common bases in DNA.

TLS Online TPP Program

#Id: 3257

#Unit 3. Fundamental Processes

Intercalating agents, such as proflavin, acridine, and ethidium, cause the deletion or addition of a base pair or even a few base pairs.