genes

Question 1

RNA differs from DNA in that RNA:

Answer 1

contains ribose as its sugar
contains uracil instead thymine

Question 2

if one strand of a DNA molecule has the sequence of bases 5’-ATTGCA-3’, what would the other strand be

Answer 2

3’-TAACGT-5’

Question 3

a particular triplet of bases in the coding sequence of DNA is AGT. the corresponding codon for the mRNA transcribed is

Answer 3

UCA

Question 4

A recessive allele on the X chromosome is responsible for red-green colour blindness in humans. A woman with normal vision whose father is colour-blind marries a colour-blind male. What is the probability that this couple’s son will be colour-blind?

Answer 4

50%

Question 5

In a population which is in Hardy-Weinberg equilibrium, the frequency of the allele a is 0.4. What is the percentage of the population which is heterozygous Aa for this allele?

Answer 5

0.48%

Question 6

one major difference between prokaryotic genes and eukaryotic genes

Answer 6

prokaryotic genes generally have introns and exons

Question 7

the pairing of purines with pyrimidines in DNA results in

Answer 7

formation of the base pairs A to T and C to G

Question 8

what is Chargaff’s rule

Answer 8

DNA should have a 1:1 ratio

Question 9

what is transcription

Answer 9

process of making RNA from DNA

Question 10

what is translation

Answer 10

process of making RNA into protein

Question 11

how many types of RNA polymerase has prokaryotic systems

Answer 11

one

Question 12

what do eurkaryotic systems use RNA polymerase II for

Answer 12

production of mRNA encoding proteins

Question 13

eukaryotic RNA require extensive processing before

Answer 13

translation

Question 14

new amino acids are carried into the ribosome linked to

Answer 14

tRNA

Question 15

regarding translation - the synthesis process is carried out by

Answer 15

the ribosome

Question 16

regarding translation - what is the smallest subunit of the ribosome

Answer 16

mRNA

Question 17

regarding translation - where is the growing site for the polypeptide

Answer 17

P or A

Question 18

what is a karyotype

Answer 18

an ordered display of the pairs of chromosomes from a cell. karyotyping shows that the chromosomes are normal in number and appearance

Question 19

how many sets of chromosomes are in a diploid cell

Answer 19

two sets of chromosomes

Question 20

how many sets of chromosomes are in a A gamete (sperm or egg) cell

Answer 20

single set of chromosomes

Question 21

for humans, what is the haploid number

Answer 21

23

Question 22

what does allele frequency mean

Answer 22

different versions of the same gene

Question 23

what is a genotype

Answer 23

genetic makeup of an organism

Question 24

what is a phenotype

Answer 24

physical makeup of an organism
(expression of the genotype)

Question 25

what is the goal of a testcross

Answer 25

to tell the genotype of an individual with the dominant phenotype

Question 26

why did gregor mendel use pea plants

Answer 26

reproduce quickly easily control how they mate achieve large number of offspring easy traits to study

Question 27

what is the locus of a gene

Answer 27

position of the gene on a chromosome

Question 28

what is mendels law of segregation

Answer 28

alleles pairs separate during gamete formation, and reunite randomly at fertilization

Question 29

what is mendels law of independent assortment

Answer 29

during meiosis, two genes of a pair sort independently into gametes, regardless of how other chromosomes are sorted

Question 30

what is epistasis

Answer 30

a gene at one locus alters the phenotype expression of a gene at a second locus - One gene determines the pigment colour (with alleles B for black and b for brown). - The other gene (with alleles C for colour and c for no colour) determines whether the pigment will be deposited in the hair.

Question 31

describe morgans fruit fly experiment

Answer 31

Morgan mated male flies with white eyes (mutant) with female flies with red eyes (wild type). The F1 generation all had red eyes. The F2 generation showed the 3:1 red:white eye ratio, but only males had white eyes. Morgan determined that the white-eyed mutant allele must be located on the X chromosome. Morgan's finding supported the chromosome theory of inheritance.

Question 32

what does deletion do

Answer 32

removes a chromosomal segment

Question 33

what does duplication do

Answer 33

repeats a chromosomal segment

Question 34

what does inversion do

Answer 34

reverses a segment within a chromosome

Question 35

what does translocation do

Answer 35

moves a segment from one chromosome to another

Question 36

what is natural selection

Answer 36

individuals with certain heritable characteristics survive and reproduce at a higher rate than other individuals

Question 37

what is the hardy-weinberg principle

Answer 37

Describes a population that is not evolving. If a population does not meet the criteria of the Hardy-Weinberg principle, it can be concluded that the population is evolving