IDK BUT DEFINETLY NOT W10

Question 1

What do mutations cause?

Answer 1

Mutations result from mistakes in DNA replication or from unrepaired damaged DNA

Question 2

What may mutations be caused from?

Answer 2

• reactive molecules produced through the normal course of metabolism
• chemicals in the environment
• radiation
• gene sequences that can jump from one position to another in a genome

Question 3

Are nucleotide substitutions mutations common?

Answer 3

No they are relatively rare

Question 4

Why do RNA viruses and retroviruses have high rates of mutations?

Answer 4

Because RNA is a less stable molecule than DNA. Also the replication if these genomes lacks a proofreading function

Question 5

What is the average mutation rate?

Answer 5

10^-10, therefor one in every 10 billion is mistakenly substituted for another

Question 6

Define hotspots

Answer 6

certain nucleotieds that are especially prone to mutation and can exhibit rates of mutation greater than the average.

Question 7

True or false, the rates of mutations differ between sexes

Answer 7

True

Question 8

How does the rate of mutations differ between somatic and germline cells?

Answer 8

In mammals the rate of mutation per nucleotide per replication is greater in somatic cells than germ cells

Question 9

What does the rate per genome depend on?

Answer 9

The size of the genome and the number of cell divisions per generation

Question 10

In humans what is the average number of newly arising nucleotide base substitution per genome in one generation?

Answer 10

30 or 60 per diploid zygote

Question 11

Why are humans able to withstand a larger number of mutations per genome?

Answer 11

because only 2.5% of the genome codes for proteins

Question 12

Which rate of mutation is more relevant to somatic cells?

Answer 12

the rate of mutation per nucleotide substitution per replication. This is cause they do not effect future generations

Question 13

Which rate of mutation is more relevant to germline cells?

Answer 13

rate of mutation per genome per generation. germline cells pass on mutations from generation to generation in an evolutionary process

Question 14

What are the two main mutations that can cause cancer?

Answer 14

• the mutation increases the activity of a gene that promotes cell growth and division
• the mutation decreases the activity of a gene that restrains cell growth and division

Question 15

What is the first hypothesis regarding how mutations arise?

Answer 15

Mutations occur without regard to an organisms needs

Question 16

What is the second hypothesis regarding how mutations arise?

Answer 16

There is some sort of feedback between the needs of an organism and the process of mutation, and the environment directs specific mutations that are beneficial to the organism.

Question 17

True or false, Most DNA damage or errors in replication are immediately removed or corrected by specialized enzymes in the cell

Answer 17

true

Question 18

What happens if a change in DNA escapes correction by DNA repair systems?

Answer 18

The change becomes stable and is sub-sequentially inherited through mitotic or meiotic division

Question 19

Define nucleotide substitution/point mutation

Answer 19

A mutation in which one base air is replaced by a different pair

Question 20

Define synonymous/silent

Answer 20

A mutation resulting in a codon that does not alter the corresponding amino acid in the polypeptide

Question 21

Define non-synonymous/missense mutations

Answer 21

A point mutation resulting in a change of amino acid

Question 22

What causes sickle cell anemia?

Answer 22

When an individual inherits two mutant B globin genes

Question 23

Define a nonsense mutation?

Answer 23

A mutation that creates a stop codon, terminating translation

Question 24

Define frameshift mutations

Answer 24

A mutation in which an insertion or deletion of some number of nucleotides that is not a multiple of three, causes a shift in the reading frame of mRNA, therefor changing all following codons

Question 25

What are transposable elements or transposons?

Answer 25

A DNA sequence that can replicate and move from one location to another in a DNA molecule

Question 26

What is one method of transposition as outlined by the corn kernel experiment?

Answer 26

• A cut and paste mechanism
• The transposon is cleaved from it original location in the genome by a specific enzyme (transposase) and inserted in a different position

Question 27

What is another method of transposition not outlined by the corn kernel experiment?

Answer 27

Transposition via a RNA intermediate.When these types of transpoable elements move (retrotransposons) retrotransposon used as a template for transcription stays behind in its original location.

Question 28

What is a duplication?

Answer 28

Is a chromosomal mutation where one region of the chromosome is present twice

Question 29

What is a deletion?

Answer 29

Is a chromosomal region where one region is missing

Question 30

What may cause deletion?

Answer 30

• An error in replication

- From joining breaks in a chromosome that can occur on either side of a deleted region

Question 31

Why can a deletion survive and persist within a population?

Answer 31

Because chromosomes are present in homologous pairs

Question 32

What is the relationship between the size of a deletion and survival?

Answer 32

Generally the larger the deletion the smaller the chance of survival.This is because organisms are sensitive to dosage (or number of copies of each gene)

Question 33

What role does small duplications play in the origin of genes and evolutionary divergence?

Answer 33

It allows one copy of the gene to change without threat to the survival of the organism. Therefor a new copy of the gene may increase survival chances and reproduction.

Question 34

What is duplication and divergence?

Answer 34

The process of creating new genes from duplicates . with the term duplicates referring to the accumulation of differences between the duplicate genes that occurs on an evolutionary time scale.

Question 35

How can duplications affect gene families?

Answer 35

Multiple rounds of duplication and divergence can giver rise to a group of genes with related functions known ad gene families

Question 36

What are inversions?

Answer 36

Chromosomal mutations where the region between two breaks in the chromosome is flipped in orientation before being repaired

Question 37

How does the accumulation of inversions over time affect evolution?

Answer 37

The accumulation of inversions over evolutionary time explains in part why the order of genes along a chromosome can differ even among closely related species.

Question 38

What is a reciprocal translocation?

Answer 38

When two non-homologous undergo an exchange in parts.Both chromosomes are broken and the terminal segments are exchanged before the breaks are repaired

Question 39

How can reciprocal translocation affect meiosis?

Answer 39

Both chromosomes involved may not move together in the same daughter cells , resulting in gametes with only one part of the reciprocal translocation. This affects gene dosage because these gametes have extra copies of genes in one chromosome and are missing genes in the other