Genetics

Question 1

Gene

Answer 1

Sequence of base pairs that encodes amino acid sequence for a protein.

Question 2

Genome

Answer 2

Full set of genetic material. Contains DNA from mother and father

Question 3

Diploid

Answer 3

2 genomes per cell, one from father and one from mother

Question 4

Phenotype

Answer 4

Observed physical traits

Question 5

Proto-oncogene

Answer 5

Normal growth promoting gene

Question 6

“Central Dogma”

Answer 6

Code for life is encoded in DNA.
We only move from DNA to RNA, not backwards.
Process of transcription to translation.

Question 7

Start codon

Answer 7

AUG
“methionine”
Sets the reading frame for translation

Question 8

Stop codons

Answer 8

UAA
UAG
UGA
Doesn’t code for an amino acid

Question 9

Unused mRNA

Answer 9

Allows RNA to last longer in cytoplasm, allowing more copies of its protein to be made

Question 10

Codon

Answer 10

3 base pairs for 1 amino acid

Question 11

Autosomes

Answer 11

Any chromosome that is not a sex chromosome

1-22

Question 12

Ploidy

Answer 12

Number of full sets of chromosomes.

Question 13

Euploid

Answer 13

Complete, normal set of chromosomes

Question 14

Aneuploid

Answer 14

Abnormal set of chromosomes (e.g. Down Syndrome, 3 copies of chromosome 21)

Question 15

Prokaryote

Answer 15

1. Single cell organisms
2. No nucleus
3. Circular DNA
4. Plasmids (separate DNA)
   One copy of chromosome per cell (haploid)

Question 16

Promoter

Answer 16

Gene sequence that instructs RNA polymerase to begin transcription

Question 17

Terminator

Answer 17

Gene sequence that instructs RNA polymerase to stop transcription

Question 18

Template strand

Answer 18

Strand of DNA from which RNA polymerase transcribes mRNA

Question 19

Introns

Answer 19

Spaces between exons that are spliced out and discarded to make open reading frame

Question 20

Spontaneous mutations

Answer 20

1. Error during DNA replication.

2. Spontaneous DNA damage.

Question 21

Induced mutation

Answer 21

1. Carcinogen induced mutation.

2. Radiation induced mutation

Question 22

Silent mutation

Answer 22

Does not result in amino acid damage

Question 23

Missense mutation

Answer 23

Results in amino acid damage

Question 24

Non-sense mutation

Answer 24

Causes a premature stop codon, stops translation early.

Question 25

Frame-shift mutation

Answer 25

Drops or adds 1 or 2 bases, moves codons over, changes the ensuing sequence of codons

Question 26

Allele

Answer 26

Variant forms of a gene sequence

Question 27

Centromere

Answer 27

Localized region where two chromatids remain connected after the chromosomes have replicated

Question 28

Kinetochore

Answer 28

Protein-bound areas of the centromere. Attach to spindle fibers forming chromosomal microtubules.

Question 29

Centriole

Answer 29

Direct the movement of chromosomes during cell division

Question 30

Spindle

Answer 30

Microtubules that distribute duplicated chromosomes to opposite ends of a dividing cell during mitosis.

Question 31

Checkpoint

Answer 31

Points at which cell checks for defects and pauses cell cycle before continuing with cell division (G1, G2/M, Metaphase)

Question 32

Polymerase

Answer 32

Enzyme that synthesizes long chains of DNA or RNA

Question 33

Ribosome

Answer 33

Organelle that contains rRNA and proteins and is essential to mRNA translation and protein synthesis

Question 34

Karyotype

Answer 34

Picture of human chromosome set, ordered from longest to shortest

Question 35

Stages of Cell Division Cycle

Answer 35

1. G1- replicate organelles
2. S-synthesize DNA
3. G2- Grow cytoplasm
4. Mitosis

Question 36

Meiosis I nondisjunction

Answer 36

Chromosomes do not separate in Meiosis I, resulting in 2 diploid cells that should be haploid

Question 37

Meiosis II nondisjunction

Answer 37

Chromosomes do not separate in meiosis II, resulting in 1 diploid that should be haploid (and 2 haploid cells)

Question 38

Sex limited phenotype

Answer 38

Phenotype that only shows up in one sex. Gene is found in autosomal chromosome, but only shows up in 1 sex

Question 39

Cohesins

Answer 39

Keep sister chromatids together until separation at anaphase

Question 40

Synaptonemal complex

Answer 40

Keeps the tetrad (2 pairs of sister chromatids) together during meiosis, involved with recombination

Question 41

Oncogene

Answer 41

A gain of function mutation of a proto-oncogene. Causes uncontrolled growth.

Question 42

Tumor suppressor gene

Answer 42

Gene that suppresses progression in the cell cycle in response to DNA damage.
e.g. P53 (involved in 50% of all cancers), BRCA-1

Question 43

Non invasive neoplasia

Answer 43

A few cancer cells that have not started invading, causing damage YET

Question 44

Preneoplasia

Answer 44

Benign, not yet cancer, but has risk to become cancer.

e.g. Adenomatous polyps

Question 45

Somatic mutations

Answer 45

Mutations that occur in somatic cells that are not passed on to children.

Question 46

Dedifferentiated

Answer 46

Cells mutate to the point that its difficult to determine where they came from.
e.g. Liver cancer cells metastasize, but its hard to tell they came from the liver

Question 47

Mosaic

Answer 47

An organism that has different genomes, because the cancer cells have different genomes than the normal cells due to mutations

Question 48

Translocation

Answer 48

When a piece of one chromosome is switched with a piece of a completely different chromosome

Question 49

What is pharmacogenomics?

Answer 49

Study to identify patients at risk for toxicity or reduced response to therapy (due to genetics) prior to medication selection.
Possible responses to therapy:
1. Benefit and toxicity
2. No benefit and toxicity
3. No benefit and no toxicity
4. Benefit and no toxicity

Question 50

Turner’s Syndrome

Answer 50

Only 1 x chromosome
No Y chromosome
Typically infertile

Question 51

Kleinfelter syndrome

Answer 51

XXY

Typically infertile