Question

name: e laila b sons of liberty: part 2 directions: write responses to each question on the lines below and please use complete sentences 1 how does goge \send a message to boston\? 2 why 3 joh explain dis 4 w hi point mutations if a single - base is deleted (called a deletion, which is also a point mutation), there can be huge effects on the organism, because this may cause a frameshift mutation. remember that the bases in the mrna are read in groups of three by the trna. if the reading frame is off by even one base, the resulting sequence will consist of an entirely different set of codons. the reading of an mrna is like reading three - letter words of a sentence. imagine the sentence: \the big dog ate the red cat.\ if you take out the second letter from \big,\ the frame will be shifted so now it will read: \the bgd oga tet her edc at.\ one single deletion makes the whole \sentence\ impossible to read. a point mutation that adds a base (known as an insertion) would also result in a frameshift. chromosomal mutations mutations may also occur in chromosomes (figure, right). these mutations are going to be fairly large mutations, possibly affecting many genes. possible types of mutations in chromosomes include: 1. deletion: when a segment of dna is lost, so there is a missing segment in the chromosome. these usually result in many genes missing from the chromosome. 2. duplication: when a segment of dna is repeated, creating a longer chromosome. these usually result in multiple copies of genes in the chromosome. 3. inversion: when a segment of dna is flipped and then reattached to the same chromosome. 4. insertion: when a segment of dna from one chromosome is added to another, unrelated chromosome. 5. translocation: when two segments from different chromosomes change positions. causes of mutations many mutations are not caused by errors in replication. mutations can happen spontaneously, and they can be caused by mutagens in the environment. some chemicals, such as those found in tobacco smoke, can be mutagens. sometimes mutagens can also cause cancer. tobacco smoke, for example, is often linked to lung cancer. mutations can arise in dna through deletion, duplication, inversion, insertion, and translocation within the chromosome. review questions (2 points): 1. what can cause dna to mutate?

Explanation:

The text mentions that mutations can happen spontaneously and be caused by mutagens in the environment like chemicals in tobacco smoke.

Answer:

Mutations can occur spontaneously and can be caused by mutagens in the environment such as certain chemicals.