bio e1

a chromosome is best described as

a single piece of DNA

where is the DNA in this picture

the purple is DNA

a gene is

a zone on a chromosome

what is translation?

making a protein from RNA

what must be true for somethin to be part of your phenotype?

it must be able to be passed to offspring, it must be able to be inherited from parents

which of these are characters?

pea flower color

what are sister chromatids?

duplicated chromosomes held together

what is the first codon

GGT or GTA

what is true about homologous chromosomes?

the genes are the same

what can you see in a karyotype?

duplicated DNA, DNA, duplicated homologous chromosomes, sister chromatids

what can be different about homologous chromosomes?

the alleles can be different?

which could have come from a parent?

B and A

why do we need haploid gametes?

so offspring can be diploid?

what does this cell show?

duplicated homologous chromosomes, sister chromatids, duplicated DNA

this will become how many chromosomes?

4

how many strands of DNA are broken in this view of crossing over?

4

crossing over results in

different sets of alleles compared to the beginning

why is this image unrealistic and potentially misleading?

crossing over is not shown

what do you get from one parent?

one chromosome from each homologous pair, one of each gene, one allele per gene

dominant alleles ( or phenotypes) are

expressed in the heterozygote

which sequence of events is correct to make a protein?p

DNA-RNA-protein

genotype of a white flower plant

pp

why only one letter in each parent box in a monohybrid cross?

because offspring have two alleles

crossing over results in different sets of alleles compared to the beginning, what does “the beginning” look like?

a normal somatic cell

correct order of events for meiosis

DNA duplication - crossing over - independent asssortment

who mates with the P2 generation

the mate with each other

which generations show two phenotypes?

P1 and F2

what is true about the genes for Mendel’s seven characters

on different chromosomes

only two homologous chromosomes in an individual, could there be more than two alleles in the population?

no- only 2 homologous chromosomes

one gene, two different alleles, standard mendelian: how many genotypes and phenotypes

3, 2

the white flower plant phenotype is

homozygous

for pea shape, round is dominant and wrinkled is recessive, how is this expressed in letters:

R is round, r is wrinkled

how many GENES are depicted in a Punnett square?

1

why do offspring probability boxes have two letters?

parents each give one allele

for the peas: P1 generation has how many genotypes?

2

for peas: genotypes of P1 generation

both are homozygous

for peas: how many genotypes in F2 generation?

3

for peas: what would the P1 genotypes be

half RRYY and half rryy

for peas, F1 genotypes will be:

all RrYy

for peas, F1 phenotypes will be

all yellow, round

what do you get from each parent?

23 chromosomes, one chromosome, one gene, one allele

mendelian genetics: which represents 2 homozygous parents who have different alleles

PP *pp

what does “P” really represent?

the actual nucleotide code on one strand of the double-stranded DNA at a specific location

rule of independent assortment

is a physical thing that happens in meiosis

two genotypes for flower color in P1 generation

both are homozygous

what are proportions of offspring phenotypes when both parents are heterozygotes?

75 dom/25 rec

what would the P1 parents genotypes be? (dihybrid)

half RRYY and half rryy

two genes; how many diff phenotypes are possible in F2?

4

two genes; how many F2 boxes will result in offspring that are round

12

what level are we talking about when we say incomplete dominance/codominance

allele

Mendel started with 50/50 in P1, by F2 the proportion of alleles in the population was

50% one and 50% the other allele

why didn’t the proportion of alleles in a population change for Mendel?

because Mendel made all the decisions

one gene: if proportions of 2 alleles in a population could change? what are plausible options?

one allele could become 100%, one allele could become 0%, proportions could fluctuate forever

how likely is no heritable advantages in the actual world

zero likely

physically, what are different alleles of the same gene

different DNA sequences found at the same locus on homologous chromosomes

a gene is expressed using incomplete dom. and the two parents in P1 are homozygous for different alleles. How many phenotypes will be expressed in the F2 generation?

3

what is a mutation?

a change in the genotype

what differentiates founder effect from population bottleneck?

founder effect results in new sub population?

what is most likely the same about homologous chromosomes?

the genes and the loci

most swiss starlings produce 4 to 5 eggs in each clutch, starlings that produce fewer eggs or more eggs than this number have reduced fitness. What best describes this situation

natural selection, stabilizing selection

what are some possible outcomes of a single mutation in a gene

might not cause a phenotypic change, could cause a change in phenotype, must cause a change in genotype

what is fitness?

an idea about future offspring

A is 20% and a is 80% of alleles, what is the proprtion of AA genotypes in the population?

4%

why is whale anatomy different?

selection resulted in important changes to whale forelimb anatomy

if two unrelated species converge on the same answer:

characters would be analogous

species converge on “the same answer” to what?

problem related to survival, reproduction, fitness

the character of flight:

evolved independently several times

what is a zygote:

a single-cell fertilized egg

can bacteria have species?

yes but not using the biological species concept

what kind of tree is this?

monophyletic