CSU Jackel life 102 exam 3

How do bacteria reproduce?

They divide

Bacterial cells perform cell division by the simple process of _.

Binary fission

The FtsZ protein is necessary for bacterial cells to perform:

Cell division & Septation

Gametes are haploid. Haploid means that the cells contain how many sets of chromosomes?

one

Chromatin, the structural component of eukaryotic chromosomes, is composed of:

DNA & Protein

Bacterial cells divide to produce new cells for:

Reproduction & Population growth

After a chromosome is replicated, the two copies are referred to as:

sister chromatids

What protein is necessary for septation and cell division in bacteria?

FtsZ

What must occur during an eukaryotic cell cycle?

• Genome replication

• Division of cell contents

• Genome segregation

The chromatin in eukaryotic chromosomes is composed of a complex of:

DNA & Protein

In a cell's life, cell growth occurs primarily during what phase?

G1 phase

The centromere contains repeated DNA sequences that can bind specific proteins. These proteins form the __, which is shaped like a disk and serves as an attachment site for __.

kinetochore, microtubule

How do we refer to a replicated chromosome and its chromatids?

One chromosome made of two sister chromatids

Order the stages of mitosis as they occur in the cell:

P(rophase)

P(rometaphase)

M(etaohase)

A(naphase)

T(elophase)

Assembly of the spindle apparatus occurs during ___ phase of mitosis.

Prophase

What is a sequence of growth, replication, and division that produces new eukaryotic cells called?

cell cycle

What usually occurs during the G1 phase?

cells are growing

During prometaphase, sister chromatids attach to the spindle by their ___, which are attached to the centromere region of each sister chromatid.

Kinetochores

During _, the chromosomes are aligned midway between the spindle poles.

Metaphase

The key event in anaphase is the simultaneous removal of __ proteins from all chromosomes.

cohesin

What apparatus is broken down during telophase?

Spindle/miotic spindle

During a eukaryotic cell cycle, when does the actual division of the cell body take place?

after mitosis

During prometaphase, which protein complex on each sister chromatid attaches to the spindle?

kinetochore

The pairs of sister chromatids align themselves in a single row along a plane half-way between the poles during which of the following phases of mitosis?

metaphase

At the beginning of which of the following phases do the centromeres of sister chromatids split apart allowing sister chromatids to separate from each other?

anaphase

During the stage of mitosis known as ___, gene expression resumes, as chromosomes uncoil.

telophase

T or F: Cell division is complete at the end of mitosis.

False

What phase of mitosis is characterized by the reformation of the nuclear envelope and the production of two separate nuclei?

telophase

If the somatic cell of an organism has 22 chromosomes, its gametes will have __ chromosomes.

11

A human gamete contains _ chromosomes.

23

During prophase I of meiosis, homologous chromosomes are held together by a complex structure called the _ complex.

synaptonemal

During which stage of meiosis do synapsis and crossing over occur?

Prophase I

During meiosis I, the ___ of each pair of sister chromatids for each homologue attach as a unit to microtubules from the same pole.

Kinetochores/centromeres

The pulling apart of homologues occurs during anaphase of _.

Meiosis I

The sister chromatids found in the daughter nuclei at the end of telophase I are not identical to each other due to which of the following?

Crossing over

What is the main function of the synaptonemal complex?

hold homologous chromosomes together

The brief period between meiosis I and meiosis II is also called:

interkinesis

During meiosis I, the kinetochores of sister chromatids act as a:

unit, to which polar microtubules attach

What are the four distinct features of meiosis I?

• Kinetochores of sister chromatids are attached to the same pole

• DNA replication is suppressed between meiosis I and II.

• Sister chromatid centromeres remain connected.

• Homologous chromosomes pair.

During anaphase I what occurs?

Homologues are pulled apart

The end result of meiosis I (telophase I) is that two nuclei are produced, each with ___.

a single, full set of replicated chromosomes

Because it does not include an S phase, the period between meiosis I and meiosis II is often called _.

interkinesis

The number of possible alignments of chromosomes in a human cell during Meiosis l is determined by using this formula: 2n. The "n" represents the _of chromosomes.

Haploid number

Genetic variability in a species is generated by what?

• Crossing over

• Independent assortment

• Random Fertilization

If an organism has 8 chromosomes in its diploid cells, how many different gametes can it produce, solely based on independent assortment of chromosomes during meiosis?

16

Genetic diversity is the raw material of:

evolution

In which of the following chromosomal entities are an individual's traits specified?

genes

The physical appearance of colonies of Streptococcus pneumoniae is related to the presence or absence of _.

A capsule

Which enzymes did Avery, MacLeod, and McCarty use in order to identify the genetic material?

RNA digesting enzymes, DNA digesting enzymes, and protein digesting enzymes

Which scientists performed a simple experiment with a phage (a bacterial virus) that confirmed previous findings that DNA is the genetic material?

Hershey and Chase

What are components of a nucleotide?

sugar, phosphate group, nitrogenous base

Genes, which contain trait specifying information, are located on:

chromosomes

Chargaff's rule indicates that the amount of A in a sample is equal to the amount of and the amount of C in a sample is equal to the amount of .

T(hymine), G(uanine)

Which form (or forms) of the bacterium Streptococcus pneumoniae can cause disease?

The S form

When trying to discover the substance responsible for transformation, Avery, MacLeod, and McCarty removed 99.98% of the ___ from their preparation and found that the transforming activity persisted.

proteins

The experiments with radioactively labeled phage that showed that DNA was the genetic material were performed by:

Hershey and Chase

X-ray diffraction images obtained by Rosalind Franklin were used to determine that the diameter of a DNA molecule is __.

2nm

Chargaff's experiments showed that the amount of adenine in a DNA sample was always the same as the amount of __.

Thymine

The backbone of a DNA strand is composed of _.

Sugars & phosphate groups

The major significance of the Hershey and Chase experiments is that they:

determined that DNA in the genetic material

The data from the Meselson-Stahl experiment supported the __ model of DNA replication.

semiconservative

Franklin determined that the structure of DNA was helical based on:

x-ray diffraction analysis

What is involved in the unwinding of DNA during replication?

Single-strand binding proteins & Helicase

The partial opening of a DNA helix to form two single strands is called:

replication fork

Repeating sugar and phosphate units in a single DNA strand make up its:

phosphodiester backbone

Based on Meselson-Stahl's experiments, it was determined that DNA replication is:

semiconservative

The enzymes in the replisome are active on:

both leading and lagging strand

The enzyme uses ATP to unwind the DNA template.

Helicase

The function of telomeres is to:

protect the ends of chromosomes

The is a macromolecular assembly of enzymes involved in DNA replication.

replisome

Let P = purple flowers and p = white, and T = tall plants and t = dwarf. If the uppercase letters represent the dominant alleles, what is the phenotype of a plant with the genotype PpTt?

purple flowers, tall

If you roll a six-sided die, what is the probability of getting either a 1 or a 2 on the first AND second roll?

1/9

Let R = red pigment and r = no pigment. In carnations, RR offspring make a lot of red pigment, rr offspring make no pigment, and Rr offspring make a small amount of red pigment, thus appearing pink. Pink carnations are therefore an example of:

incomplete dominance

In Mendel's experiments on seed color in pea plants, when a dominant yellow seed-bearing plant was crossed with a recessive green seed-bearing plant, what was the approximate phenotypic ratio among the offspring?

All yellow, Since the yellow plant is dominant over the green plant, a homozygous dominant yellow crossed with a homozygous recessive green would lead to all of the offspring being yellow.

Let P = purple flowers, p = white, T = tall plants, and t = dwarf. Of the 16 possible gamete combinations in the dihybrid cross between 2 double heterozygotes, how many would produce the phenotype white, tall?

3

Let P = purple flowers, p = white, T = tall plants, and t = dwarf. Of the 16 possible gamete combinations in the dihybrid cross, 3 combinations produced the phenotype white and tall. What two plants would have to cross to make this occur?

2 double heterozygotes

The physician who, in 1902, proposed a relationship between genes and the production of enzymes.

Archibald Garrod

The central dogma describes:

Information flow as DNA to RNA to protein

A three-nucleotide sequence in mRNA, that codes for a particular amino acid, is called

codon

The AUG codon has a dual function. It serves as the _ codon and it encodes the amino acid _.

start, methionine (met)

Archibald Garrod concluded that patients suffering from alkaptonuria lack the ___ necessary to catalyze the breakdown of homogentisic acid.

enzyme

How many RNA polymerases do bacteria have?

A single RNA polymerase

A codon is composed of:

3 nucleotides

What are two functions of the AUG codon?

It encodes the amino acid methionine. It acts as a start codon.

In a bacterial transcription unit, the role of the __ is to form a recognition and binding site for the RNA polymerase.

promoter

How do eukaryotic transcription factors help form the initiation complex?

They recruit RNA polymerase to the promoter.

Describe a major difference between prokaryotic and eukaryotic mRNA transcription?

In eukaryotes, a primary transcript is first synthesized which is modified to become the mature mRNA.

Eukaryotic genes may contain noncoding regions known as __ because they interrupt the sequence of a gene.

introns

Identify the process the pre-mRNA undergoes to create a functional mRNA.

splicing

Before it can bind to the promoter, a eukaryotic RNA polymerase II has to be recruited by __.

several transcription factors

Genome

All of the DNA in a cell

Proteome

All of the proteins produced in a cell

Transcriptome

ChoiceAll of the RNAs produced in a cell

The RNA synthesized by RNA polymerase II is known as the transcript. It is later modified into the mature mRNA.

primary

What are the two functional ends of a tRNA?

acceptor stem and anticodon loop

To create a functional RNA, the pre-mRNA undergoes a process known as splicing. During the splicing process, the are removed and the remaining _ are connected to each other.

Introns & extrons

Each aminoacyl-tRNA synthetase present in a cell recognizes _ of the 20 common amino acids. For credit, please answer with a number.

One

What is the main function of the promoter in a bacterial transcription unit?

To form a recognition and binding site for RNA polymerase

Like transcription, the process of in ribosomes occurs in three stages called initiation, elongation, and termination.

translation

Eukaryotic genes may contain noncoding regions known as because they interrupt the sequence of a gene.

introns