Bio Lab Exam 3

Exception to homologous chromosomes

-Sex chromosome of male (XY) -Females have 23 pairs homologous chromosome (22 autosome and XX) -males have 22 pair homologous chromosome (22 autosome and one pair non homo sex chromosome (XY)

metaphase

-chromosomes undergo a microtubule "tug of water" until all chromosomes are aligned along the middle of the cell (between the two poles). This position is referred to as metaphase plate

Cells can go up to 3 main stages

-interphase -mitosis -cytokinesis

what occurs in mitosis?

-nuclear envelope dissolves -chromosomes are sorted to opposite ends of cell - two nuclei are reformed into the cell

Prometaphse

-nuclear envelope dissolves -microtubules invade the nuclear area -microtubules attach to specialized protein structures located on the chromosome called kinetochores -microtubules referred to as kinetochore microtubules -non kinetochore mictotubules interact with microtubules extending from the opposite centrosome completing the formation of the mitotic spindle

Mitosis is subdivided into

-prophase, - pro-metaphase, -metaphase, -anaphase, -telophase

Telophase

-single stranded chromosomes arrive at the opposite poles of the cell, and a nuclear membrane forms around them, The chromosomes un condense to form chromatin. spindle fibers disperse and cytokinesis begins

Anaphase

-sister chromatids sep at the kinetochore and move to opposite ends of the cell

number of divisions mitosis vs meiosis

1 vs 2

Mendel found

1.) there are alternative forms of genes (alleles) for each trait 2.) For each inherited trait a diploid organism recieves two genes (one from each parent) 3.) A gamete (sperm or egg) carries only one allele of each gene b/c homologous chromosomes sep during meiosis (law of seg) 4.) For those traits inherited by complete dom, one allele of the pair is usually expressed dominant) while the other is not recessieve)

The typical ratio of possible outcomes from the cross of two heterozygotes of a gene would be:

1:2:1 (Dominant: Heterozygote: Recessive)

Number of cell produced in mitosis vs meiosis

2 vs. 5

Mom and dad contribute to

22 autosomes & 1 sex chromosome- each chromosome from mom corresponds to chromosome from dad

If all genes behave in the same way as the genes Mendel studied in pea plants, what would be the expected ratio you would find in the F2 generation of flies for eye color (offspring of a cross between two heterozygous individuals).

3 of one color: 1 of the other color

number of chromosomes in daughter cells mitosis vs meiosis

30 vs 23

How many cells are formed after Meiosis II? Are they haploid or diploid?

4 unique haploid cells

How many chromosomes in the parent cell? How many in the daughter cell?

46 chromosomes and daughter is 46 too. 23 each

How many non duplicated chromosomes are there?

46 chromosomes, 23 pairs

How many duplicated chromosomes are present at each stage of mitosis?

46, duplicated to 92 chromatids

At what temperature does the denaturation of DNA double helix take place?

94 C

mutation

A change in a gene or chromosome.

four possible phenotypes

A, B, AB, O (recessive)

six possible genotype

AA,AO,AB,BB,BO,OO

phenotype

An organism's physical appearance, or visible traits.

In which exact phase of Meiosis do sister chromatids separate?

Anaphase II

phase when sister chromatids separate mitosis vs meiosis

Anaphase, Anaphase II

Blood type A

Anti A serum (Agglutination) Anti B serum (No agglutination)

Blood type AB

Anti A serum (Aggutination) Anti B Serum (Agglutination)

Blood type B

Anti A serum (no agglutination) Anti B Serum (Agglutination)

Blood type O

Anti A serum (no agglutination) Anti B serum (no agglutination)

Autosomes

Any chromosome that is not a sex chromosome

1. Observe well the picture in "b" above. Compare the overall size of the starfish embryo in the zygote, 2-cell, 4-cell and 8-cell stages. What do you see? How do you explain this? Show your understanding of the phases of the cell cycle.

As observed in part b, this is the process of early cleavage where the volume of the egg cytoplasm starts to divide into numerous smaller cells. This separates the cytoplasm and forms the daughter cells which start to transition into countless cell together; all taken place during the cytokinesis stage.

Codominance inheritance

Both alleles for a trait are expressed at the same time

homologous chromosome

Chromosomes that have the same sequence of genes and the same structure

homologous chromosomes

Corresponding autosomes, similar in length and encode for the same genes, however sequence of DNA tends to be different giving rise to different features

For example, a child with blood type AB, mother with blood type A

Could not have a man with type O blood as father

_____________ occurs when the phenotypic effect of the individuals allele status at one gene depends on the individual's allele status at another gene.

Epistasis

What is the name given to the cells able to undergo meiosis? Are these cells haploid or diploid?

Germ Line Cells, Haploid

After a diploid cell undergoes Meiosis I, two daughter cells are formed. Are these daughter cells haploid or diploid?

Haploid

steps of pcr

In brief terms, during PCR the DNA sample is denatured to produce single stranded DNA, called template DNA, to which the primers can bind. DNA polymerase then adds nucleotide bases to the end of each primer, using the template DNA as a guide to extend the primer thereby producing new double stranded DNA. This process is repeated for a number of cycles to enrich the DNA sample for the desired genes targeted by the primers. Since each cycle of PCR involves creating two new double stranded DNAs from each DNA molecule

· Which stage of mitosis took the longest? The shortest? Is this what you would expect? Why or why not?

Interphase is the longest because its where the cell is growing and copying DNA. Metaphase shortest because the chromosomes align in the middle.

The stages of the cell cycle are:

Interphase, Mitosis and Cytokinesis

Chi-square

Involves categorical variables. Looks at 2 distributions of categorical data to see if they differ from each other. testing null hypothesis

centrosomes

Microtubule-organizing centers that help to form and organize the mitotic spindle during mitosis

Could JoAnn belong to Devyn and Kobe? Why or why not?

No, Joann wouldn't belong to Devyn and Kobe. Kobe is an AB genotype, so he would be able to give either allele to Joann, as A and B are dominant over O. Joann wouldn't be able to have OO genotype and O phenotype with Kobe

A allele is dominant over

O alleles

What did Mendel assume about alleles?

Only two alleles of each gene are available in the entire population.

Presence of Cleft Chin - Does your chin have a distinctive inward folding of the skin (think of John Travolta) or not. If so, you exhibit a dominant trait, if not, you are recessive. The alleles are represented by the appropriate case of the letter 'C'.

Phenotype = C Genotype= c

Crossing Thumbs - Without thinking, quickly clasp your hands together so your fingers interlace. Is your left thumb on top of your right (dominant trait), or right on top of left (recessive trait)? NOTE: try doing it the opposite way, it will feel "weird". The alleles are represented by the appropriate case of the letter 'L'.

Phenotype = L genotype=l

Genotype AA

Phenotype A, antigen A

Hyperextension of Thumb - Put either thumb out as if you were trying to hitch a ride. Examine the section of your thumb that bears the nail. Does this bone (the distal phalange) angle backwards at a distinct angle or just the entire thumb remains fairly straight from tip to base? If the thumb remains straight, you are observing the dominant trait, if it is bent (called "hitchhiker's thumb"), you are seeing the recessive trait. The alleles are represented by the appropriate case of the letter 'B'.

Phenotype- B genotype- b

Replication

Process of copying DNA prior to cell division

spores

Produced by meiosis. Grow into haploid organisms by mitosis.

Property of life

Reproduction , process in which an organism makes more individuals similar to itself.

Centromere

Specific region of proteins that serve as a binding region when the chromosome itself is duplicated

Pay close attention to your results. Describe any deviations of the expected Mendelian pattern. Discuss possible reasons for this/these deviation(s).

The deviation of the mendelian pattern is that the 3:1 ratio will occur when the allele has a relationship of dominance and recessiveness. Reasons can be from genetic or environmental factors.

cleavage furrow

The first sign of cleavage in an animal cell; a shallow groove in the cell surface near the old metaphase plate.

Which sex chromosome (X or Y) carries the gene for eye color in Drosophila? Justify your answer based on the data you collected in the previous sections.

The gene for eye color is located on the X chromosome. Females have the XX chromosome so they would carry two copies of this gene, while males carry one. Based on the data above the red-eyed are most dominant for the eye color.

Sex in fruit flies is determined in a similar way as in humans. Thus, the following is true:

XX females XY males

Could Monica belong to John and Ann? Why or why not?

Yes, Monica could belong to John and Ann. John has an A allele that can be passed on to Monica and Ann has a genotype BO which the O can be passed on too. Monica will have an AO and her phenotype will be A..

Could JoAnn belong to John and Ann? Why or why not?

Yes. Joann could belong to John and Ann. Ann has genotype BO, so she can give the O allele to Joann and John has an AO genotype so he can give the O to Joanna. Joanna would be OO and phenotype would be O blood.

Could Monica belong to Devyn and Kobe? Why or why not?

Yes. Monica could belong to Devyn and Kobe. Kobe is an AB genotype, so he can pass the A allele to Monica. Devyn has an OO genotype and can easily pass the O allele to Monica. Monica would have an AO genotype and the phenotype would be A.

cytokinesis is the result of

a fiber ring composed of a protein forming around the center of the cell and contracting. (cleavage furrow) . pinches the cell into two daughter cells

when a electrical current is applied in a solution

a molecule of solute with a positive charge will migrate to the cathode (neg, electrode) and molecules of solute with a negative charge will migrate to the anode (positive electrode).

Mitotic spindle

a structure made of microtubules that controls chromosome movement during mitosis

meiosis

a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores. original chromsome number is reduced by half

There are 3 alleles

a,b,o

If all genes behave in the same way as the genes Mendel studied in pea plants, what would be the expected eye color ratio you would find in the offspring of a P generation cross of flies (white-eyed x red-eyed)?

all red or all white

Each chromosome is composed of

arms, centromere, kinetochore

character is to trait

as gene is to allele

Mendel later did breeding which tracked two genes

at the same tie. when he crossed two individuals who were hetro for both genes, it created dihybrid crosses.

The _________, a formed cavity inside the embryo, is the last stage of cleavage.

blastocoel

During gastrulation, the division inward of _________ produces a tube inside the embryo, which is called the ________.

blastomeres; archenteron

How many pairs of homologous chromosomes were in the parent cell? How many were in the daughter cell?

both 23

blastomeres

cells of the blastula

gametes

cells that carry each half of the genetic information

arms of a chromosome

chromatid; generally longest and most visible portion of chromosomes

When the cell readies itself for mitosis

chromatin condenses molecule coils and tightly compacts and is visible (referred to as chromosomes)

when the cell is not dividing

chromosomal material called chromatin forms long thin spiraling strands that cannot be seen except with a powerful microscope

Genetic material in eukaryotic cells is organized into a series of

chromosomes

genotype

comb of alleles within an individual: homozygous dominant, homoygous recessive or heterozygous

In unicellular organisms

completion of each cell cycle results in the production of a new unicellular organism

Chromosome

complex molecule formed of proteins and DNA (source of genetic information)

DNA (deoxyribonucleic acid)

considered a hereditary code of life because it possesses the info that determines an organisms characteristics and is transmitted from one gen to the next.

Somatic cells (non-reproductive cells)

contains nuclei, 46 chromosomes arranged in 23 pairs

genes

determine what we look like and how we function, inherited from out parents according to scientific principles. Can understand how genetic diseases are passed from generation to generationn

Assuming that these couples are faithful and each girl belongs to one of these couples, it is evident that Monica belongs to:

devyn and kobe

Because humans contain two complete sets of chromosomes we are referred to as

diploid

Because their are two copies of every chromosome somatic cells are said to be

diploid( often abbreviated as 2n, where n equals the # of chromosomes in one set) all somatic cells have exactly the same genetic makeup

Cytokinesis

division of the cytoplasm (entire cell)

Mitosis

division of the nucleus

Major patterns of genetic inheritance include everything EXCEPT:

dominance inheritance

traist

expressed variations of a specific character

Character is to related to allele as gene is related to trait

false

In gel electrophoresis, an electric current is applied across the gel so that one end of the gel has a positive charge and the other end has a negative charge. DNA has a positive charge so the wells will be placed on the negative charged side to be able to migrate across the gel.

false

Meiosis results in four identical daughter cells

false

PCR is a DNA amplifying in vivio method

false

The first stage of animal development is called gastrulation where there are embryonic stem cells forming.

false

crossing over

follows synapsis and occurs when chromosomes swap, homologous regions leading to formation of recombinant chromosomes that contain new gene combination

germ cells

formation of gametes occur in multicellular eukaryotes in specialized cells called

the end result of meiosis is

four haploid cells, each are different from the other

In animals meiosis produces

gametes

section of DNA

gene, code for synthesis of enzymes that regulate cell reactions to determine a specific cell activity or apperance known as a character

S Phase

genetic material DNA replicated

alleles

genetic variations produced, since thesse traits are passed on or inherited from gen to gen via cell division these are genetic traits

Meiosis occurs with specialized________ cells

germ

In Metabolism one aspect is

growth (increase in cell body size ) another is reproduction/replication (duplication) of self

cells containing only one set of chromosomes are called

haploid, when hapolid gametes join together a diploid cell (zygote) is produced

Spindle fibers

help pull apart the cell during replication and are made up of micrtubules

What is the most likely genotypes of red 1 females and red 2 females, respectively?

heterozygous;homozygous

mendel also discovered

homo and hetro traits

The genotype for John is: (answer from Table 4 in your Theory and Instructions document)

i^Ai

The genotype for John Jr. is: (answer from Table 4 in your Theory and Instructions document)

i^Ai^B

the genotype for Ann is: (answer from Table 4 in your Theory and Instructions document)

i^Bi

The genotype for Monica is: (answer from Table 4 in your Theory and Instructions document)

i^a^i

The genotype for Kobe is: (answer from Table 4 in your Theory and Instructions document)

i^a^i^b

As Mendel discovered through these experiments

if the genes are located on different chromosomes, the inheritance of one will not affect the inheritance of the other (Law of Independent Assortment).hat is because during meiosis, chromosomes align randomly before separating. The phenotype ratio for the F2 generation in dihybrid crosses will be 9:3:3:1 (9 both dominant traits : 3 first dominant, second recessive : 3 first recessive, second dominant : 1 both recessive traits)

The genotype for Devyn is: (answer from Table 4 in your Theory and Instructions document)

ii

The genotype for JoAnn is: (answer from Table 4 in your Theory and Instructions document)

ii

Cell cycle

in more complex eukaryotic cells- cell cycle ranges from 8-24 hours because cells must make new organelles, cytoplasm and duplicate dna within the nucleus and prepare for physical division of the nucleus and cell components into 2 identical daughter cells

Interphase

involves the growth of cell itself up to a size where mitosis can occur (each and every chromosome is exactly duplicated)

the combination of alleles in an individual (genotype) determine which antigen

is present at the surface of red blood cells

Assuming that these couples are faithful and each girl belongs to one of these couples, it is evident that JoAnn belongs to:

john and Ann

G 2

mitochondria and other organelles are replicated in prep for division of cytoplasm later in M phase

During the latter stages of mitosis

mitosis vesicles are released from golgi appartus, and are located at opp sends of the cell. fusion results in formation of 2 daughter cells.

Each sample has the DNA fragments along with a mix of

mix of loading dye or "tracking dye", and usually glycerol. The dye allows us to view the progress of the DNA as it moves through the gel, and the glycerol weighs the DNA into the well so that it won't rise up and migrate out of the well. Separation of DNA proceeds from heaviest to smallest (as shown in the figure below). A DNA ladder has fragments of known sizes and is usually loaded in the same gel as the samples for comparison.

blood type has

multiple alleles

for sexual reproduction, gametes

must be created that have half the number of chromosomes.

sex-linked genes

n humans, these chromosomes are the X chromosome and the Y chromosome. Because females have two X chromosomes, they have two alleles for each of the genes in these chromosomes. Therefore, in females, these genes are going to behave as any of the other genes located in the autosomes. However, males have one X and one Y chromosome, so they only have one allele for each of the genes located in these chromosomes

phase when homologous chromosomes separate mitosis vs. meiosis

n/a , anaphase

all eukaryotic cells have a

nucleus

Dna is contained within the nucleus

of almost every cell in the human body. NA is specially packed through a series of events to fit easily within the cell's nucleus. In order to condense the length of a DNA molecule, the double helix wraps itself around proteins, fold back on itself, and coils into a compact chromosome. When the DNA from multiple chromosomes is extracted from multiple cells, it can be viewed by the naked eye and looks similar to strands of cotton. In this lab activity, you will isolate your own chromosomal DNA from a large quantity of cheek epithelial cells.

sexual reproduction

offspring is a genetic mix of two parents. fusion of the paternal and maternal cells carrying half of the genetic info

Complete inheritance

one allele is completely dominant over another

asexual reproduction

only one individual, useful when enviromental conditions are stable and organism is well adapted. favorable and quick. The new individual produced is genetically identical to the parent- a clone. Unique individuals only arise when a mutation occurs

gel electrophoresis

operates on the principle of sep of molecules (usually proteins and nucleic acids ) based on size

Mendel used

pea plants which are diploid and use sexual reproduction to discover many aspects of genetics

Widow's Peak - This term refers to a distinct downward point along the hairline around the center of the forehead. If present, you exhibit a dominant trait, if your hairline is straight across, you are recessive. The alleles are represented by the appropriate case of the letter 'W'.

phenotype =F genotype=f

Genotype AO

phenotype A, Antigen A

Genotype AB

phenotype AB, antigen both A and B

Genotype BO

phenotype B and antigen B

Genotype BB

phenotype B, antigen B

Genotype OO

phenotype O, antigen neither

Hair on Fingers - Hold your hands out straight and point the backs of your hands towards the light. Look along your fingers and see if there is hair on the fingers between the joints (if you have dark hair, you probably will not need to hold your hands up to observe the presence or absence). If present, this is referred to as "mid-digit hair" and is dominant, if no hair is present along the backs of the fingers, the trait is recessive. The alleles are represented by the appropriate case of the letter 'T'.

phenotype-T Genotype-t

Ear Lobes - Does the lower margin of your ear attach directly to your head (recessive trait), or does it hang, forming a distinct 'lobe' (dominant)? The alleles are represented by the appropriate case of the letter 'F'.

phenotype=F genotype=f

Cytokenesis is different in animals cells than plant cells because

plant cells have a cell wall and animal cells do not. when a plant cell divide it has to make a new cell wall. achieved w/formation of a cell plate during cytokinesis

G 1 phase

primary growth

Binary fission

process in which a single chromosome is duplicated, the cell doubles in size and then divides. This results in two identical individuals that are the same size as their parent cell

In this phase, the nuclear envelope has completely disintegrated, and the mitotic spindle attaches to the kinetochores of the chromosomes.

prometaphase

Crossing over of chromosomes is one of the events that creates unique diversity and this occurs during which phase of Meiosis

prophase I

Meiosis phases

prophase,metaphase, anaphase telophase. Undergoes two rounds of cellular division and cytokinesis. resulting in 4 daughter cells. nterphase, Meiosis I (Prophase I, Metaphase I, Anaphase I, and Telophase I), a brief growth period, and then Meiosis II (Prophase II, Metaphase II, Anaphase II, and Telophase II)

which trait is dominant for eye color?

red

The additional cells of a multicellular organism comes from

repeated mitotic divisions throughout life

Synapsis

replicated chromosomes align with corresponding homologous chromosomes to form tetrads and chromosomes can then interwine

In plant cells a

rigid cell plate forms a polysaccharide material, similar to cellulose in the center of the cell which grows outward toward the margins to separate the cytoplasm and form two daughter cells

Polymerase chain reaction (PCR)

s a type of technology utilized in many fields of forensics as well as medicine that allows a DNA molecule to be copied multiple times, or amplified . This process is catalyzed by an enzyme called DNA polymerase . The 1 DNA molecule has to be tagged in a way to tell the enzyme w

Cell Cycle

series of event cells go through to replicate/divide

Gametes

sex cells

gametes

sex cells, formed by cellular division called meiosis , after the fusion of sperm and egg

Multicellular organisms usually reproduce by

sexual reproduction which involves fertilization of an egg by a sperm

Both homozygous dominant and heterozygous genotypes will have the same phenotype,

so the phenotype ratio will be 3:1 (3 dominant trait : 1 recessive trait)

DNA replication only happens once but cells divide twice

so the resulting cells are haploid

most cells in the body are

somatic cells, have two copies of each chromosome.

nuclei of all cells of a multicellular organism have

specific # of chromosomes

Kinetochore

specific disk of protein on centromere that serve as an anchoring point for specific protein tubules called spindle fibers that develop during mitosis

In plants meiosis produces

spores

During prophase I

synapsis and crossing over occurs

an individual inherits the A allele from one parent and the B allele from the other,

that person will have blood type AB. Thus, the A and B alleles are considered codominant

blood type of an individual is the same as

the antigen on the surface of the cells . person with blood type A has antigen A. This person can't receive blood from someone with blood type B. A person with blood type A produces antibodies against blood type B. Antibodies are proteins produced by white blood cells that "neutralize" an invader and fight infection

In a multiceullar organism

the completion of cycle results in the growth of the organisms body, which is accompanied by development, changes in structure and function of various cells and region of the body

In complete dominance,

the expression of the phenotype in a heterozygous individual is determined by one allele, the dominant allele. This type of expression is referred to as a Mendelian pattern of inheritance.

F1 generation

the first generation of offspring obtained from an experimental cross of two organisms. (homo dominant x homo recessive = all hetero offspring)

Blastocoel

the fluid-filled cavity of a blastula

growth

the increase in cell number, cell size and overall size o the organism.

all cells continue to multiply

the info stored in the genes of dna may tell these cells to develop different shapes and functions each contributing something to the whole organism.

parental (P) generation

the parental organisms in a genetic cross. homozygous dominant X homozygous recessive

development

the process of structural and functional change

Genetics

the study of inheritance that deals with patters in chromosomes (DNA molecule w/protein) determines cell organism structure and unction

If two members of F1 generation of heterozygous mate (monohybrid cross)

they can produce (F2 gen) w/ all 3 possible genotypes of a ration 1:2:1 ((1 homozygous dominant : 2 heterozygous : 1 homozygous recessive)

Prokaryotic cells are short because

they lack a nucleus and do not undergo mitosis and cytokinesis but undergo binary fission

An example of codominance is when a mother has A bloodtype, father has B, but child has AB bloodtype

true

Denaturation, annealing and extension are repeated for 30 cycles in PCR.

true

Genetics is the study of inheritance in which sections of DNA code for patterns that enable cell/organism structure and function.

true

Human DNA profiles can be used to identify the origin of a DNA sample at a crime scene or test for parentage.

true

In the formation of gametes, both spermatogenesis and oogenesis start with mitosis.

true

Males cannot be carriers of an x-linked gene.

true

Mendel assumed the expression of a trait is completely controlled by one gene.

true

Mitosis happens in asexual reproduction, growth of organisms and in the repair of damaged tissues.

true

The chi-square test is always testing if there is no significant difference between an expected and observed result.

true

If a person received the A allele from one parent and O allele from another parent, that person will have

type A

codominance

when both alleles are expressed in a heterozygous individual. Thus, we see the following genotypes and phenotypes of the ABO blood typing system

incomplete inheritance

when heterozygous for a trait the phenotype is a blending of the 2 alleles

Which of the crosses above is most like the P generation of Mendel's peas?

white male X red 2 female

The punnet square allows

you to predict all possible offspring from parental genotypes

1. What are the major differences between Prophase I and Prophase II, as mentioned in the video?

· Daughter cells only have 1 copy of each homologous chromosome, In prophase II no synapsis of homologous chromosomes or crossing over.

Explain what synapsis and crossing over are. In which phase do they occur?

· The paring of two chromosomes, occurs during prophase I

In gel electrophoresis instead of passing an electrical current through a solution,

, a gel medium is used. A common gel-forming material is the polysaccharide agarose. The agarose gel acts as a type of molecular sieve to facilitate separation of smaller fragments of material. The gel is placed into a box between the two electrical components: cathode and anode. A small amount of each sample is added to each "well" or pre-cast notches at the top of the gel.

Prophase

- Replicated chromosomes (sister chromatids) are attached via centromere - Chromosomes begin to condense and become visible as distinct irregular linear structures -Replicated centrosomes begin to migrate to opposite poles of the cell and start to form microtubules that will attach to and separate sister chromatids and form mitotic spindle