Introduction to Genetics

Question 1

Transmission genetics

Answer 1

Transfer of genetic information from parents to offspring; understand and predict how traits are inherited

Question 2

Molecular genetics

Answer 2

deals w/ DNA and the genome; understanding gene structure, expression and function; Central Dogma

Question 3

What is the genetic material in eukaryotes and prokaryotes? What is the genetic material in some viruses?

Answer 3

Eukaryotes and prokaryotes: DNA

Some viruses: RNA

Question 4

Genome

Answer 4

an organism’s full DNA sequence, or the DNA or RNA sequence of a virus

Question 5

What is DNA composed of and look like?

Answer 5

two chains each made of nucleotides composed of a deoxyribose sugar, a phosphate group, and a base; a double helix

Question 6

What are the four bases in DNA?

Answer 6

Adenine, Thymine, Guanine, and Cytosine

Question 7

What base is replaced in RNA and what is it called?

Answer 7

In RNA, Uracil replaces Thymine

Question 8

Genes

Answer 8

specific base sequences passing traits from parents to offspring

Question 9

How is genetic material in cells organized?

Answer 9

into chromosomes

Question 10

What is the difference between how DNA is organized in prokaryotes and eukaryotes?

Answer 10

In prokaryotes, DNA is in a singular, circular chromosome.

In eukaryotes, DNA is either in the form of chromosome in a nucleus or in a circular molecule in an organelle.

Question 11

Endosymbiosis theory

Answer 11

Organelles appeared from prokaryotes; Ex: mitochondria and chloroplast

Question 12

Chromosome

Answer 12

composed of DNA and protein; circular in prokaryotes and linear in eukaryotes

Question 13

Centromere

Answer 13

constricted part of a chromosome that holds together two chromatids

Question 14

Nucleosomes

Answer 14

DNA packaged efficiently in a chromosome, coiled around molecular spools

Question 15

Each nucleosome is composed of eight proteins called?

Answer 15

Histones

Question 16

Chromatin

Answer 16

DNA + associating nucleosomes

Question 17

Ploidy

Answer 17

number of sets of chromosomes

Question 18

N

Answer 18

chromosome set

Question 19

1N

Answer 19

1 set of chromosomes; haploid organisms have this

Question 20

2N

Answer 20

2 sets of chromosomes; diploid organisms have this

Question 21

Do haploid or diploid organisms have homologous pairs of chromosomes?

Answer 21

Diploid; 2 versions of each chromosome, 1 from each parent

Question 22

How many chromosomes do the human species have? How many pairs of autosomes and how many pairs of sex-determining chromosomes do humans have?

Answer 22

46 total chromosomes, 22 pairs of autosomes and 1 pair of sex-determining chromosomes

Question 23

Diploscapter pachys

Answer 23

a worm; “a single chromosome”; hasn’t had sex in 18 million yrs

Question 24

Oxytricha trifallax

Answer 24

cilliate; “16,000 chromosomes”; organism that builds itself a new genome every time it has sex

Question 25

What are the two examples of organisms that are polyploid?

Answer 25

Strawberries and salamanders

Question 26

Polyploid

Answer 26

more than 2 sets of chromosomes

Question 27

How much data does a strawberry store?

Answer 27

200 Terabytes

Question 28

Central Dogma

Answer 28

transfer of instructions stored in DNA (genotype) into proteins that perform physical action and make physical form (phenotype)

Question 29

What are the steps to Central Dogma?

Answer 29

1. DNA replication 2. Transcription (DNA ->RNA) 3. Translation (RNA->proteins)

Question 30

Reverse transcription

Answer 30

cDNA is made from a RNA template; cDNA has no introns compared to regular DNA

Question 31

Population genetics

Answer 31

Change in genetic information among individuals over generations; understand and predict trait/gene evolution within populations

Question 32

Quantitative genetics

Answer 32

deals w/ quantitative traits, which are phenotypes that vary continuously (such as height or mass)

Question 33

What are the four sources of variation in DNA?

Answer 33

Mutations, recombination, selection, epigenetics

Question 34

Mutations

Answer 34

heritable changes in genetic material

Question 35

Recombination

Answer 35

exchange of genetic material; produced by enzymes that cut and rejoin DNA molecules

Question 36

Selection

Answer 36

favoring particular gene combinations in a given environment

Question 37

Epigenetics

Answer 37

changes in phenotype in the absence of any underlying change in the DNA sequence

Question 38

Genetic maps

Answer 38

sites of genes (loci) on chromosomes, and genetic distances between them calculated from recombination in experimental crosses; show whether genes w/ related functions are on the same chromosome; useful in cloning and genome sequencing

Question 39

Desirable qualities for an experimental organism (model organism) include:

Answer 39

1. well-known genetic history 2. short life cycle (generations can be studied in little time) 3. large number of offspring per mating 4. ease of growing and handling 5. marked genetic variation