ch. 6 and 7 Genetics

When I is positive (positive interference), it indicates what?

a decrease in the observed number than expected

what are bacteriophages made of?

a protein coat and genetic material

what did the studies of Bateson and Punnett suggest?

a type of coupling in some manner

describe F' factor formation.

a) F factor that contains a part of bacterial chromosome b) It is formed when F factor escapes from bacterial chromosome imprecisely

Genetic recombination by _______________ can produce new combinations of alleles on chromosomes

crossing over

When the known deletion strain has r103 mutated sequence, wild type can be formed from ___________

crossing over

__________: a physical exchange of pieces between homologous chromosomes that most commonly occurs during prophase of meiosis I.

crossing over

Recombinants are from ____________________

crossing over during meiosis

In the experiment by Baetson and Punnett, which of the following observations suggested genetic linkage in the sweet pea? a) A 9:3:3:1 was observed in the F2 offspring b) A 9:3:3:1 was not observed in the F2 offspring c) An unusually high number of F2 offspring had the phenotypes of the P generation. d) both b and c suggested linkage

d

When a crossover occurs, it _____________ the chances of a second crossover.

decreases

_________ is Used on identifying and localizing rII mutations to specific known regions

deletion mapping

A ___________ describes a mating experiment between two organisms that are identically hybrid for two traits.

dihybrid cross

Alfred Sturtevant used the frequency of crossing over in _____________

dihybrid cross

during Nonhomologous /illegitimate recombination, DNA incorporates ________________.

into random sites in the chromosome

____________________ seeks to establish distances between 2 or more mutations within the same gene.

intragenic mapping

____________ is Produced by crossing over between two rII mutants on the same gene but different sites.

intragenic recombination

how are bacterial genes transferred by Hfr strain to F' strain?

laterally

what were the principles of Wollman and Jacob once they completed their experiments? a) Transfer of genes during conjugation was _________ b) Use blender to _____________ between bacterial cells (no harm to the cell) c) The time it took for a gene to enter the recipient cell is directly related to its _______________ (a) The order of genes could be determined by ________________ (b) To determine if genes had been transferred, they used minimal media according to ________________

linear interrupt mating (conjugation) order on the chromosome interrupting mating at different times the gene of interest

Crossing over may alter ________ of genes

linkage

___________: a single chromosome, or all of the genes found on a single chromosome, which are linked together (also called a synteny group)

linkage group

In genetics, a ________ is a specific, fixed position on a chromosome where a particular gene or genetic marker is located.

locus

in the lytic cycle, new phage particles are released through __________________

lyses of bacterial cells

Incorporation of a part of bacterial chromosome may happen during the assembly of new phages during the __________

lytic cycle

_____________: a type of growth cycle for bacteriophage in which the phage directs the synthesis of many copies of genetic material and coat proteins. These components then assemble to make new phages. When synthesis and assembly are completed, the bacterial host cell is lysed, and the newly made phages are released into the environment.

lytic cycle

_____ the relative distance between genes on a single chromosome. In a test cross, it is defined as the number of recombinant genes divided by the total number of offspring, multiplied by 100.

map distance

__________: a unit of map distance obtained from genetic crosses. One of these is equivalent to 1% of recombinant offspring in a testcross.

map unit (mu)

__________: a type of growth medium for microorganisms that contains a mixture of nutrients that are required for growth; nothing additional has been added.

minimal medium

__________ is a unit of measure used in bacterial conjugation experiments ; refers to the relative time it takes for genes to first enter a recipient strain during conjugation.

minutes

________: crossing over that occurs during mitosis and produces a pair of recombinant chromosomes.

mitotic recombination

_____________: a natural process of transformation that occurs in a certain species of bacteria.

natural transformation

in the lytic cycle, inserted phage DNA makes what?

new phage particles

___________: the exchange of DNA between nonhomologous segments of chromosomes or plasmids.

nonhomologous recombination

New allelic combinations produce _______________ cells

nonparental (recombinant)

______: an ascus that contains four spores that all have nonparental combination of alleles.

nonparental ditype

which asci type contains four spores with nonparental combinations?

nonparental ditype

More _____________________ present, the genes are further apart

nonparental offspring

___________: refers to a cell or offspring that carries the same combinations of alleles found in the chromosomes of their parents or in the chromosomes of the parental generation in linkage experiments.

nonrecombinant offspring

a ___________ is a complex of DNA (or RNA) and a protein.

nucleoprotein

___________: a hypothesis that assumes that there is no real difference between the observed and expected values.

null hypothesis

___________: An ascus containing eight ascospores, produced in species in which the tetrad normally undergoes a postmeiotic mitotic division.

octad

____________: the location of an F factor or within the chromosome of an Hfr strain that is the initiation site for transfer of DNA from one bacterium to another during conjugation.

origin of transfer

Cells with original combination of alleles are called ______________________

parental (nonrecombinant) offspring

____________: an ascus that contains four spores with the parental combinations of alleles

parental ditype

which asci type contains four spores with the parental combinations of the alleles only?

parental ditype

what are the different types of asci?

parental ditype (PD) tetratype (T) nonparental ditype (NPD)

____________are viruses that infect bacteria

phages

Donor cell (F+ strain) extends a ________

pilus

Exporter sends nucleoprotein to the recipient cell through _______

pilus

A viral _________ is a visible structure formed after introducing a viral sample to a cell culture grown on some nutrient medium. The virus will replicate and spread, generating regions of cell destruction known as __________.

plaque plaques

Rapid lysis mutant forms large and clearly defined ____________compared to wild-type

plaques

__________ is a general term for a DNA molecule (most often circular) that exists independently of the chromosomal DNA. Some are used as vectors in cloning experiments.

plasmid

Double-crossover rarely occurs due to ______________.

positive interference

___________: a phenomenon in which a crossover that occurs in one region of a chromosome decreases the probability that another crossover will occur nearby.

positive interference

A ______________ is a bacteriophage (often shortened to "phage") genome inserted and integrated into the circular bacterial DNA chromosome or exists as an extrachromosomal plasmid. This is a latent form of a phage, in which the viral genes are present in the bacterium without causing disruption of the bacterial cell.

prophage

what do all types of asci have in common?

they are all tetrads

__________ is a form of genetic transfer between bacterial cells in which a virus (bacteriophage) transfers bacterial DNA from one bacterium to another.

transduction

___________: Transferring bacterial chromosome from one bacterium to another through virus

transduction

__________: when a bacterial cell takes up a plasmid vector segment of chromosomal DNA from the environment.

transformation

____________: when a normal cell is converted to a malignant cell.

transformation

___________: It is the cross between the two individuals of a species for studying inheritance of three pairs of factors or alleles belonging to three different genes.

trihybrid cross

__________ are responsible for mitotic recombination.

twin spots

In ______________, the transfer of genetic material is from parents to offspring. It may be through sexual or asexual reproduction. In contrast, the horizontal gene transfer is the movement of genetic material from a donor organism to a recipient organism that is not its offspring.

vertical gene transfer

Homoallelic mutations will never produce __________ recombinants

wild-type

during step 3 of a trihybrid cross, Parental phenotypes should occur __________ within the offspring

with the greatest frequency

If the rII phages have mutations in different genes, then each phage can complement to produce plaques in _______ This is called what?

K12λ Complementation

When rII phages have mutations in the same gene, they will not be able to make plaque in ______ this is called what?

K12λ Noncomplementation

generalized transduction was first described by:

Lederberg and Zinder (1952) by using Salmonella typhimurium

______________- tests for the goodness of fit between the observed and expected data

Chi square

________ is equivalent to 'gene'

Cistron

_________, also called cis-trans test, in genetics, test for determining whether two mutations associated with a specific phenotype represent two different forms of the same gene (alleles) or are variations of two different genes.

Complementation test

____________ test reveals if two different mutations are in the same gene or not

Complementation test

_________________: Direct physical contact between bacteria

Conjugation

___________________ provide the relative order of genes on a bacterial chromosome and __________________ provides map distances between closely linked genes on the bacterial chromosome

Conjugation experiments cotransduction

conjugation was first studied using what organism?

E. coli

Presence of the ________ allows conjugation from the donor cell

F factor

____________: A DNA sequence or plasmid that confers certain bacteria the ability to produce a sex pilus for conjugation with other bacteria.

F factor

how did the F2 generation in Bateson and Punnett's studies differ than that of Mendel's studies?

F2 showed 15.6:1:1.4:4.5 ratio which differs from expected 9:3:3:1 ratio

__________________: a technique of dna mapping which makes use of extremely rare recombination events where the crossing over occurs between two genes or two alleles of a gene that are only a few nucleotides apart.

Fine structure mapping

______________ is the process by which a segment of DNA is transferred between two bacteria

Gene transfer

__________________ occurs when random pieces of bacterial DNA are packaged into a phage. It happens when a phage is in the lytic stage, at the moment that the viral DNA is packaged into phage heads. If the virus replicates using 'headful packaging', it attempts to fill the head with genetic material.

Generalized transduction

_________________ indicates two genes that are located on the same chromosome

Genetic linkage

________________ determines the linear order of genes on a chromosome

Genetic mapping

transformation was first described by __________________.

Griffith (1928)

___________: a bacterial strain in which the F factor has become integrated into the bacterial chromosome. During conjugation, it can transfer segments of the bacterial chromosome.

Hfr strain

_________________ is one of two cycles of viral reproduction (the lytic cycle being the other). It is characterized by integration of the bacteriophage nucleic acid into the host bacterium's genome or formation of a circular replicon in the bacterial cytoplasm.

Lysogenic cycle

which type of phage uses the lytic cycle?

Virulent phages

who mapped E.coli chromosome through conjugation experiment?

Wollman and Jacob in 1950s

Alfred Sturtevant's map was constructed of ________________.

X-linked traits

__________________: Transmission of genes from mother to daughter cells

Vertical gene transfer

_______________ is a strain that lacks the genes necessary to synthesize one or more nutritional requirements

Auxotroph

experiments by Creighton and McClintock discovered what?

(a) Translocation between chromosome 8 and 9 (b) Abnormal chromosome 9 has knob on one end and translocation on the other end (c) Chromosome 9 provide two genes Kernel colored (C) or white (c) Kernel starchy texture (Wx) or waxy texture (wx)

One map unit equals a ____ recombination frequency

1%

Benzer coined ____________ - Smallest genetic unit that gives a negative complementation test

'cistron'

homologous recombination forms __________________ and replaces existing genotypes

'heteroduplex'

Areas of the gene that contain high numbers of mutations are called ______________

'hot spot'

In deletion mapping, rII mutant of interest (r103) was coinfected with ___________________

'known deletion strains'

Chromosomes are often called ____________________

'linkage groups'

Physical location of a particular gene on a chromosome is called _____________

'locus'

T DNA-relaxase complex is called _________________.

'nucleoprotein'

which type of phages use the lysogenic cycle?

'temperate phages'

describe the transformation process.

(1) DNA binds to cell surface competence factor (2) DNA is cut into smaller pieces by extracellular endoculease enzyme (3) Double-stranded DNA is denatured and single stranded DNA enter the cell (4) Integration of foreign DNA into bacterial chromosome

Genetic maps can:

(1) explain the complexity and genetic organization of the species (2) illustrate the principles of particular inherited traits of an organism (3) provide information for gene cloning and other applications for molecular technique (4) be used in evolutionary studies by comparing with other organisms (5) provide practical benefits: diagnosis, prevention of genetic diseases, agricultural use

what were the interpretations of Creighton and McClintock's experiments?

(a) Recombinants were produced (b) Crossing over was seen

describe the first division segregation (fds) pattern.

(a) There is no crossing over between the gene of interest and the centromere (b) Order of allele arrangement is 4:4

How long is the E. coli genetic map?

100 minutes

Mapping by cotransduction experiment can be used to map genes that are within _______________ of each other

2 minutes

Humans have ___ autosomal linkage groups, an __ linkage group, and a ___ linkage group

22 X Y

how many steps are in a trihybrid cross?

5

At map distances approaching ___________________, it is less accurate from actual map distance -Influenced by greater chance of ______________ once it passes 50, it _________________________

50.0 (50% recombination) undetected multiple crossover does not actively reflect map distance

The first genetic map was made by whom?

Alfred Sturtevant (1911)

________________ are viruses that infect bacteria and used extensively in the study of bacteria

Bacteriophages

________________ have a limited capacity for moving bacterial DNA -No more than _______% of the bacterial chromosome

Bacteriophages 1-2.5

Who Discovered two traits that did not assort independently from sweet pea?

Bateson and Punnett (1904)

___________ test reveals if two different mutations are in the same gene or not

Benzer's test

_______________ consists of two homologous chromosomes with a pair of sister-chromatids each

Bivalent chromosomes

describe the fourth step of a trihybrid cross.

Calculate the map distance between pairs of genes

_________________-: Process by which two bacterial genes that are close together are moved by a bacteriophage from one cell to another

Cotransduction

_____________ is the simultaneous transformation of two or more genes.

Cotransformation

_________________ is when two genes are moved into the genome together from environment

Cotransformation

______________ loads the nucleoprotein into the exporter, which is in contact with pilus

Coupling factor

who worked with corn and found chromosomal abnormalities?

Creighton and McClintock

________________: exchange of genetic material between homologous chromosmes

Cross over

who discovered mitotic recombination?

Curt Stern

____________: DNA sequences found in certain species of bacteria that are needed for a DNA fragment to be taken up during transformation.

DNA uptake signal sequences

____________ are located side-by-side in the ascus. This allows the mapping of the distance between a ____________.

Daughter cells gene and centromere of the chromosome

_________________ is a process by which a DNA feature (mutation, DNA polymorphism, or MIC-limited DNA segment) can be genetically mapped to a segment of a MIC chromosome, defined by deletion ends, using a panel of deletion homozygotes.

Deletion mapping

________________ between two genes can rarely occur

Double crossovers

Referring to allelic mutant genes that have mutations at the same site

Homoallelic

___________ is the movement of genes between two different organisms.

Horizontal gene transfer

________________ is the process by which two DNA molecules not sharing homology to each other are joined.

Illegitimate recombination (IR)

_________________ may recombine these mutations and result in wild-type genes

Intragenic crossing over

____________ studies showed that mutations can occur at many different sites within a single gene

Intragenic mapping

____________: Amount of time it takes for an entire chromosome to be transferred during Hfr mating

Minute

who discovered X-linked genes?

Morgan (1911)

what was the biggest take away from Bernard Davis's experiments?

Most, but not all, bacteria can transfer genetic material by conjugation

_____________________ occurs when living bacteria take up DNA from environment

Natural transformation

When the known deletion strain does not have r103 mutated sequence, no plaque is formed regardless crossing over -_____________________

Noncomplementation

_______________ occurs when foreign DNA doesn't have compatible segments with recipient cell.

Nonhomologous /illegitimate recombination

_______________ have the same combinations of alleles as one of the parental strains

Nonrecombinant offspring

describe the second division segregation (sds) pattern.

Order of allele arrangement may be 2:2:2:2 or 2:4:2 -Crossing over occurs between the centromere and the gene of interest (SDS-crossover) (a) The percent of asci containing SDS patterns may be used to calculate the map distance (b) In an SDS, only 1/2 of the spores are product of crossover

__________________-: in which the spores are arranged according to the order in meiotic division.

Ordered Tetrad Analysis

________ acts as an attachment site for the two bacteria

Pilus

_____________ is an area where bacterial lawn on an agar plate is lysed and cleared by phage infection

Plaque

during the lysogenic cycle, ___________ enters into the lytic cycle when it is activated.

Prophage

______________ has all the genes necessary to synthesis nutritional requirements

Prototroph

________________- have different combinations of alleles than either of the parental strains

Recombinant offspring

______________ are fewer in number than _______________ offspring

Recombinants nonrecombinant

_________________ correlates to the distance between genes on a chromosome

Recombination rate

describe the first step of a trihybrid cross.

Step 1) Cross two true-breeding strains that differ with regard to three alleles

describe the second step of a trihybrid cross.

Step 2) Perform a testcross by mating F1 female heterozygotes to homozygous male

describe the third step of a trihybrid cross.

Step 3) Collect the F2 data

what did Bateson and Punnett (1904) study?

Study of flower color and pollen length

_____________: Two or more genes that are located on the same chromosome

Synteny

Relaxome cuts one of the DNA strands forming __________. T DNA separated from its __________________.

T DNA complementary strand

__________: Uses virus as a carrier of genetic material between two bacteria

Transduction

______________: Uptake genetic material from the environment

Transformation

________________ may be used to get map distance and order of genes on chromosome

Trihybrid cross

______________: Adjacent areas of the same organism show different phenotypes

Twin spots

what did the experiment of Bernard Davis utilize?

U-shaped tube with a filter and applied suction and pressure - DNA can go through the filter, but bacteria cannot go through

what are the functions of plasmids on bacteria?

a) Fertility factor: Conjugation b) Resistance plasmids (R factors): Antibiotics resistance c) Degradative plasmids: Digestion of macromolecules d) Col-plasmids: Carry genes for colicines, proteins that kill other bacteria e) Virulence plasmids: Carry genes that make bacteria pathogenic

what are the characteristics of plasmids?

a) The circular extrachromosomal DNA in bacteria b) Plasmids that can integrate into a bacterial chromosome are called 'episomes' (ex.: F factor) c) Plasmids have origin of replication and replicate independently d) Often found many (10-100s) copies per bacterium

Morgan suggested what three hypothesis to explain his results?

a. All three genes are located on the same chromosome (the X chromosome) b. Crossing over produces new combinations of alleles c. The likelihood of crossing over depends on the distance between the two genes

_________: the acquisition of antibiotic resistance by a bacterial strain, which may result from genetic alterations in the bacterial genome, but often occurs because the bacterium has taken up a gene or a plasmid from another bacterial strain.

acquired antibiotic resistance

______________ is the transformation of bacteria that occurs via experimental treatments.

artificial transformation

Genes that are close together tend to be transmitted from parent to offspring _______________.

as a group

________: a sac that contains haploid spores of fungi.

ascus

Fungi are haploid organisms that frequently reproduce ____________.

asexually

_________: a strain that cannot synthesize a particular nutrient and needs that nutrient to be added to its growth medium.

auxotroph

the first studies of conjugation used two _____________ strains. What were these strains?

auxotrophic Biotin and methionine auxotroph ; Phenylalanine and threonine auxotroph

________: a structure in which two pairs of homologous sister chromatids have synapsed (i.e. aligned) with each other.

bivalent

what were the three traits Morgan studied in Drosophila?

body color, eye color and wing shape

what is another term for a map unit?

centimorgan

Relaxase helps T DNA to form _______________.

circular DNA

A ________ is an alternative term for "gene".

cistron

K12λ bacteria are ___________ with two strains of rII

coinfected

______________ are proteins that are needed for bacterial cells to become naturally transformed by extracellular DNA.

competence factors

a ____________ is a peptide secreted by a certain species of bacteria that allows them to become competent for transformation.

competence-stimulating peptide (csp)

________________ are cells that can take up DNA from the environment or an extracellular medium.

competent cells

_________________ occurs when two strains of an organism with different homozygous recessive mutations that produce the same mutant phenotype have offspring that express the wild-type phenotype when mated or crossed. It will ordinarily occur if the mutations are in different genes.

complementation

______________ is a form of genetic transfer between bacteria that involves direct physical interaction between two bacterial cells. One bacterium acts as a donor and transfers the genetic material to the recipient.

conjugation

________________ was first described by Lederberg and Tatum (1946).

conjugation

in the general transduction experiment, the strains were combined and genetic transfer occurred, otherwise known as what?

conjugation

Once contact is made, the pili shorten and bring the bacteria close together, creating a ___________.

conjugation bridge

a __________ is a connection bridge between two bacterial cells that provides a passageway for DNA during conjugation.

conjugation bridge

Most genes for conjugation are contained on ____________________.

conjugative F factors

Genes on a chromosome are physically _______________

connected to one another

what is the fifth step in a trihybrid cross?

construct the map

Genes may be mapped by __________________ in the same manner as cotransduction

cotransformation

Nucleoprotein is exported from the donor cell by help from __________________

coupling factor

Further the genes are apart, the more likely _______________ will occur

crossing over

Genes that are far apart on the same chromosome may assort independently due to _____________.

crossing over

fungi Also reproduce sexually by the fusion of two haploid cells, which Forms _____________. The diploid zygote then proceeds through meiosis to produce ___________________. In some species, this is followed immediately by ___________________________. These cells are contained within a sac called _____________________.

diploid zygote four haploid spores (tetrad) a mitotic division, producing octad an ascus (plural: asci)

F factors may be transferred to a conjugation-defective cell, making it a _______________.

donor cell

the lowest phenotype frequency in a trihybrid cross is indicative that a _____________ is present.

double crossover

which phenotypes indicate which of the three genes is in the middle?

double crossover

Single stranded DNA of both donor and recipient cells replicates and form _______________.

double-stranded DNA

mitotic crossing over is rare on which type of cells?

embryonic

___________: the genetic element that can replicate independently of the chromosomal DNA but can also occasionally integrate into the chromosomal DNA.

episome

Donor strains contain a __________________.

fertility factor (F factor) on a plasmid

Lederberg and Zinder proved bacteriophages as the ______________

filterable agents

There has been no crossing over between the gene and the centromere when two alleles segregate in to separate nuclei at the first division. This is called _______________ and produces the 2:2 (or 4:4 in an octad) pattern

first-division segregation

genetic linkage occurs because...

genes that are close together on the same chromosome tend to be transmitted together to offspring

_________: the phenomenon in which genes that are close together on the same chromosome tend to be transmitted as a unit.

genetic linkage

The linear order of genes on the chromosome is called a _____________________.

genetic linkage map

what is another name for a genetic map?

genetic linkage map

__________: a diagram that shows the relative locations of genes or other DNA segments on a chromosome.

genetic map

_________: any method used to determine the linear order and distance of separation among genes that are linked to each other along the same chromosome. This term is also used to describe the use of genetic crosses to determine the linear order of genes.

genetic mapping

_________: the process in which alleles are assorted and then passed on to offspring in combinations that are different from those that are found in the parents.

genetic recombination

_________: the process in which chromosomes are broken and then rejoined to form a novel genetic combination.

genetic recombination

during Lederberg and Zinder experiment, some bacteria were able to grow on minimal media, which is evidence of ___________.

genetic recombination

___________: the transfer of genetic material from one bacterial cell to another.

genetic transfer

a ________________ is a region of double-stranded DNA that contains one or more base mismatches.

heteroduplex

When two mutations are located exactly on the same location in the gene, they are called _____________

homoallelic

_____________ occurs when foreign DNA has compatible segments with recipient cells.

homologous recombination

_____________: the exchange of similar or identical DNA segments between homologous chromosomes.

homologous recombination

Large percentages of bacterial genomes are the result of _______________________

horizontal gene transfer

_______________ is the transfer of genes from one individual to another individual that is not its offspring.

horizontal gene transfer

Acquired antibiotic resistance may be due to the __________________ of genes from resistant species

horizontal movement

an area of DNA that is likely to mutate (change).

hot spot

Each chromosome contains approximately how many genes?

hundreds to thousands

____________: a method used in conjugation experiments in which the length of time that the bacteria spend conjugating is stopped by a blender treatment or a harsh agitation.

interrupted mating

___________: a strain that does not need a particular nutrient in its growth medium.

prototroph

_____ phages will not infect bacterial strain K12λ

rII

_________: describes DNA molecules that are produced by molecular techniques in which segments of DNA are joined to each other in ways that differ from their original arrangement in their native chromosomal sites. The cloning of DNA into vectors is an example.

recombinant

__________: refers to the cell or offspring that carries a new combination of traits or alleles due to crossing over or due to independent assortment of chromosomes.

recombinant

Testcross allows to distinguish between __________ and ___________.

recombinant and nonrecombinant

Map distance is ______________.

recombinant frequency

Crossing over may produce ___________________.

recombinant genotypes

___________: an offspring that has inherited a combination of alleles or a combination of traits that is different from either of their parents. For unlinked genes, recombinant offspring are produced via independent assortment. For linked genes, recombinant offspring are produced by crossing over.

recombinant offspring

during step 3 of a trihybrid cross, Next highest frequency should be the offspring with a _______________ between one of the genes

recombination event

Probability of a double-crossover in a trihybrid cross is equal to the product of the ______________.

recombination frequency

Most of relaxome proteins are released but ____________ which remains bound to the T DNA

relaxase

In donor cell, a protein complex called _____________ recognizes the origin of transfer on the F factor

relaxome

____________: a protein complex that recognizes the origin of transfer in F factors and other conjugative plasmids, cuts on DNA strand, and aids in the transfer of T DNA.

relaxosome

__________ have both haploid and diploid life cycles

sac fungi

There has been crossing over between the gene and the centromere when two alleles segregate in to separate nuclei at the second division. This is called ____________ and produces the 2:2:2:2 or 2:4:2 (in an octad) patterns (MII pattern).

second-division segregation

_________________: is a structure on the surface of bacterial cells that acts as an attachment site to promote the binding of bacteria to one another.

sex pilus

The arrangement of the spores within an ascus is __________ specific

species

_________: haploid cells that are produced by certain species, such as fungi.

spores

________: the situation in which two or more genes are located on the same chromosome.

synteny

Use _________ to construct genetic linkage map

testcross

_____________: an experimental cross between a recessive individual and an individual whose genotype the experimenter wishes to determine.

testcross

_____________: an experimental cross used for mapping the distance between genes in which an individual that is heterozygous for two or more genes is crossed with an individual that is heterozygous recessive for those same genes.

testcross

__________: a group of four fungal spores contained within an ascus.

tetrad

__________: the structure formed by the association of four sister chromatids during meiosis.

tetrad

________: an ascus that has two spores with the parental combination of alleles and two spores with nonparental combinations.

tetratype

which asci type contains mix of parental and nonparental genotypes in an ascus?

tetratype

When I is negative, it indicates what?

that a crossover enhances the chances of second crossover

what did Bateson and Punnett discover?

that flower color and pollen length were linked

Likelihood of crossing over depends on what?

the distance between two genes