Mutation

Question 1

Permanent change in the DNA
sequence.

Answer 1

Mutation

Question 2

Result in a change to either a DNA base
pair or a chromosome.

Answer 2

Mutation

Question 3

Responsible for the huge diversity of
genes found among organisms because
mutations are the ultimate source of
new genes

Answer 3

Mutation

Question 4

Mutations of one or a few nucleotides can
affect ______ structure and function.

Answer 4

protein

Question 5

When it occurs in a gamete or in a cell that gives rise to gametes, it may be transmitted to offspring and to future generations.

Answer 5

Point Mutations or Gene Mutations

Question 6

If the mutation has an adverse effect on the phenotype of a person, mutant condition =

Answer 6

genetic disorder or hereditary disease

Question 7

Mutations can result from

Answer 7

• errors in the DNA
• replication during cell division
• exposure to viral mutagens, or viral infection

Question 8

_________________ which occur in eggs or sperms, these mutations can be passed onto offspring while _____________ which occur in body cells are not hereditary.

Answer 8

Germline Mutations; Somatic Mutations

Question 9

a change in a single DNA base.

Answer 9

Point Mutation

Question 10

a purine replaces a purine (A to G or G to A) or a pyrimidine replaces a pyrimidine (C to T or T to C).

Answer 10

Transition

Question 11

a purine replaces a pyrimidine or vice versa (A or G to T or C).

Answer 11

Transversion

Question 12

TYPES OF SMALL-SCALE MUTATIONS

Answer 12

• Point mutations within a gene:
• Insertions and deletions can involve one or more nucleotide pairs.

Question 13

(TYPES OF SMALL-SCALE MUTATIONS)
Point mutations within a gene:

Answer 13

• Single nucleotide-pair substitutions
• Nucleotide-pair insertions or deletions.

Question 14

Replacement of one nucleotide and its partner with another pair of nucleotides.

Answer 14

Nucleotide-pair substitution

Question 15

Some substitutions have no effect on the encoded protein, owing to the redundancy of the genetic code.

Answer 15

Nucleotide-pair substitution

Question 16

Example: if 3’-CCG-5’ on the template strand mutated to 3’-CCA-5’. The mRNA codon that used to be GGC would become GGU, but a glycine would still be inserted at the proper location in the protein.

Answer 16

Nucleotide-pair substitution

Question 17

A change in a nucleotide pair may transform
one codon into another that is translated into
the same amino acid =

Answer 17

silent mutations

Question 18

has no observable effect on the phenotype (can occur outside genes as well)

Answer 18

Silent mutation

Question 19

substitutions that change one amino acid to another one

Answer 19

Missense

Question 20

such a mutation have a little effect on the protein

Answer 20

Missense

Question 21

Alteration of a single amino acid in a crucial area can significantly alter protein activity

Answer 21

Missense

Question 22

Substitution mutations are usually_______________ : altered codon still codes for an amino acid

Answer 22

missense mutations

Question 23

there are abnormalities in the hemoglobin that changes or mutations that replace one amino acid into another. This also now changes the property of the hemoglobin as a whole.

Answer 23

Hemoglobinopathies

Question 24

can also change a codon for an amino acid into a stop codon:

Answer 24

Point Mutation or Nonsense mutation

Question 25

the resulting polypeptide will be shorter; it causes translation to be terminated prematurely than the polypeptide encoded by the normal gene.

Answer 25

Nonsense mutation

Question 26

change in DNA that causes a protein to terminate or end its translation earlier than expected.

Answer 26

Stop mutation

Question 27

Nearly all nonsense mutations lead to
_________________

Answer 27

nonfunctional proteins

Question 28

occurs when there is a substitution of a nucleotide making the template mRNA have a different code but still produces the same amino acid

Answer 28

Silent Mutation

Question 29

occurs when the substitution changes amino acid into a completely different amino acid. And this can have two variable effects: little to no effect or significant changes when it occurs at crucial areas.

Answer 29

Missense Mutation

Question 30

Leads to a shorter template because of the protein stop codon. And proteins that are produced here are non-functional

Answer 30

Nonsense Mutation

Question 31

Abnormal Hemoglobins

Answer 31

Hemoglobinopathies

Question 32

AA substitution in the beta chains-substitution of valine for glutamic acid in the 6th position in the normal beta chain.

Causes sickling RBC under conditions of reduced oxygen concentration.

Answer 32

Hemoglobin S

Question 33

Substitution of lysine for glutamic acid on the 6th position of the beta chain.

RBC appear as target cells, or, less often, precipitated Hb C crystal may be demonstrated.

Answer 33

Hemoglobin C

Question 34

replaces GLUTAMIC ACID at 6th position = Hb S (insoluble)

Answer 34

VALINE

Question 35

replaces GLUTAMIC ACID at 6th position = Hb C (insoluble)

Answer 35

LYSINE

Question 36

replaces GLUTAMIC ACID at 26th position = Hb E

Answer 36

LYSINE

Question 37

Additions or losses of nucleotide pairs in a
gene

Answer 37

Insertions and Deletions

Question 38

Insertion or deletion of nucleotides may alter the reading frame of the genetic message, the triplet grouping of nucleotides on the mRNA that is read during translation =

Answer 38

Frameshift Mutation

Question 39

occurs whenever the number of nucleotides inserted or deleted is not multiple of three.

Answer 39

Frameshift Mutation

Question 40

All nucleotides downstream of the deletion of insertion will be improperly grouped into codons.

Answer 40

Frameshift Mutation

Question 41

The Result will be extensive missense, usually ending sooner or later in nonsense and premature termination.

Answer 41

Frameshift Mutation

Question 42

Unless the frameshift is very near the
end of the gene, the protein is almost
certain to be __________

Answer 42

nonfunctional

Question 43

Variations from the normal condition and chromosome structure or chromosome number.

Answer 43

Chromosomal Mutations or Chromosomal Aberrations

Question 44

Phenotype of an organism can be affected by small-scale changes involving individual genes

Large scale chromosomal changes can also affect an organism’s phenotype.

Answer 44

Alterations of chromosome number and structure

Question 45

Physical and chemical disturbances, as well as errors during meiosis, can damage chromosomes in major ways or alter their number in a cell.

Answer 45

Alterations of chromosome number and structure

Question 46

Large scale chromosomal alterations in humans and other mammals often lead to spontaneous abortion or miscarriage of a fetus and individuals born with these types of genetic defects commonly exhibit various developmental disorders

Answer 46

Alterations of chromosome number and structure

Question 47

Occurs in meiosis 1 and meiosis 2

Members of a pair of homologous chromosomes do not move apart properly during meiosis 1 or sister chromatids fail to separate during meiosis 2

Answer 47

Nondisjunction

Question 48

One Gamete receives two of the same type of chromosome and other gamete receives no copy

Answer 48

Nondisjunction

Question 49

If either of the apparent gametes unites with a normal one at fertilization the zygote
will also have an abnormal number of a particular chromosome

Answer 49

aneuploid