Exam 2

Unwinding, Complementary base pairing, and joining

3 steps of DNA replication

One duplication chromosome consisting of two sister chromatids.

A dyad consists of

A zygote with monosomy

A human egg with 22 chromosomes that is fertilized by a normal sperm will result in

Two chromosome with two sister chromatids each

A tetrad is composed of

A;T;G;C

According to Chargaff's rules, __________ always pairs with __________, and ___________ always pairs with __________.

diploidly

All but which one of following results from nondisjunction?

Alternative versions of the same trait

Alleles are

0

An individual with the karyotype 48, XYYY would have how many Barr bodies?

A cell with two or more nuclei

Cytokinesis usually, but not always, follows mitosis. If a cell undergoes mitosis and not cytokinesis, this would result in

The two resulting DNA molecules each have one new DNA strand and one old strand from the original DNA molecules.

DNA replication is called semiconservative because

2

During G1 stage of interphase, a diploid organism contains how many copies of each gene?

Genetic material is exchanged between non sister chromatids, resulting in new combinations of alleles.

During crossing over

Face opposite spindle poles

During meiosis 1, the homologous chromosomes of a tetrad

Chromosomes line up separately, with sister chromatids facing opposite spindle poles

During meiosis 2

The law of independent assortment

During meiosis, each pair of alleles on the homologous chromosomes sorts independently from all other pairs of alleles. This statement corresponds to

Interphase; S

During which stage of the cell cycle do the chromosomes duplicate?

Freckles

Example of phenotype

haploid, haploid, diploid

Following meiosis I, the daughter cells are ______; following meiosis II, the daughter cells are ______; and following mitosis, the daughter cells are _______.

45, XO

How is Turner Syndrome presented on a karotype?

there is DNA damage

If a cell stops at the G1 checkpoint, this is most likely due to what problem?

The trait is an autosomal dominant trait

If both parents express a particular trait, but their child does not, what does this indicate about the trait?

recessive trait

In a one-trait testcross, the phenotype that disappears in the F1 generation of a homozygous dominant and homozygous recessive cross is the

Meiosis produces haploid gametes and fertilization creates a diploid cell that divides by mitosis to produce a new individual.

In human life cycle

The number of chromosomes is cut in half in gametes.

It is essential that germ cells undergo meiosis so that

Crossing-over occurs in prophase of meiosis 1 but not in prophase of meiosis 2

One major difference between meiosis 1 and meiosis 2 is that

False, because both parents could carry the recessive allele.

Parents with the dominant phenotype cannot have offspring with the recessive phenotype.

May double back and base pair with itself ,whereas DNA does not

RNA differs from DNA because RNA

Nondisjunction

The failure of sister chromatids to separate during meiosis is called

All possible combinations of gametes based on a cross between the two parents.

The filled-in squares of a Punnett square represent

There was only one variety of pea available to Mendel.

The garden pea was a good model for Mendel's genetics experiments. Which of the following is not true regarding this model organism?

Adults who are diploid and produce haploid gametes; these gametes fuse to produce a diploid zygote which grows into an adult.

The human life cycle consists of

The possibility of non disjunction increases

The possibility of Down syndrome increases as the mother's age increases because

When the plant self-pollinates, all the offspring resemble the parent, and are homozygous for that gene

What does true-bleeding mean?

Centromere

What is the structure that holds together the two sister chromatids that form a chromosome?

Chromosome

What structure is formed by two sister chromatids being held together by a centromere?

During mitosis

When during the cell cycle are chromosomes visible?

Thymine

Which base is found in DNA , but not in RNA?

one factor must be dominant and one factor recessive in each individual

Which is NOT true according to Mendel's law and meiosis?

Interphase- shortest stage of the cell cycle

Which is not a correct association?

tRNA

Which of the following allows a cell to decipher the genetic codes?

pairing of homologous chromosomes

Which of the following does not occur twice during meiosis?

Turner Syndrome

Which of the following human syndromes is a monosomy?

Exhibit contact inhibition

Which of the following is not a characteristic of cancer cells?

Cause an organism to grow

Which of the following is not a function of meiosis?

Each gamete contains two genes for each trait.

Which of the following is not true with regard to the law of segregation?

prophase, metaphase, anaphase, telophase

Which of the following represents the phases of mitosis in their proper sequence?

Meiosis involves two divisions and produces four non identical daughter nuclei

Which of the following statements is correct?

Translation

Which process requires the participation of all three types of RNA

The regulation of the cell cycle is lost and uncontrolled cell division occurs

cancer occurs when

Translocation

when chromosome parts break off and attach to different chromosomes.