Cell Biology Test 1 Studying

The initial importance of membrane-enclosing self replicating RNA molecules and associated proteins was that they

Maintained these molecules as a unit capable of reproduction and evolution

At the time life arose on Earth, Earth’s atmosphere contained abundant amounts of all of the following except

O2

Which energy producing process is thought to have come first during cellular evolution?

Glycolysis

• (Know order of which energy producing processes arose- Glycolysis, photosynthesis, oxidative phosphorylation)

The bacterial genome is located in a portion of the cell called the

Nucleoid

Which of the following is a key difference in the origin of replication between prokaryotes and eukaryotes?

Eukaryotes have multiple origins while prokaryotes have a single origin

In which type of organism does DNA replication occur more quickly?

Prokaryotes, because they have a smaller genome and simper replication machinery

What is the primary function of the enzyme DNA polymerase III in prokaryotic replication?

Synthesizing new DNA strands in the 5’ to 3’ direction

Which of the following correctly describes the differences in the role of primase in prokaryotic and eukaryotic replication?

Eukaryotic primase is a part of a complex with DNA polymerase alpha, while prokaryotic primase works independently

Which of the following distinguishes lagging strand synthesis in prokaryotes and eukaryotes?

Prokaryotes produce longer Okazaki fragments compared to eukaryotes

Which statement about dominant and recessive traits is correct

Individual with one dominant and one recessive allele will show the dominant phenotype

During semiconservative DNA replication, what is the result after one round of replication?

Two DNA molecules, each with one parent strand and one newly synthesized strand

What is the primary function of RNA interference (RNAi)?

To degrade specific mRNA molecules and reduce protein synthesis

In CRISPR/Cas9 gene editing, what directs the Cas9 enzyme to the specific target DNA sequence?

gRNA (guide RNA)

Which method utilizes a labeled DNA probe to identify specific DNA sequences after electrophoresis?

Southern blotting

What is the primary function of restriction endonucleases in recombinant DNA technology?

Join DNA fragments together

Which of the following statements best describes the structure of most eukaryotic genes?

They contain exons interspersed with noncoding introns that are removed during RNA processing

What was a key finding from studies using adenovirus as a model for gene expression?

Single adenovirus mRNA hybridizes to several separated regions of the viral DNA, revealing the presence of introns

What is the significance of alternative splicing in eukaryotic gene expression?

Allows a single gene to give rise to multiple mRNA and protein variants

In vitro

Using chemicals and cellular components

In vivo

Using living cells or organisms

In silico

Using computer analysis of large amounts of data

In situ

In the sample location

Glycolysis equation

C6H12O6 turns into 2C3H3O3 (aka 2 pyruvate)

Photosynthesis

6CO2 + 6H2O turns into C6H12O6 + 6 O2

Oxidate Metabolism

C6H12O6 + 6 CO2 + 6H2O (generates 36-38)

Stanley Miller applied electrical sparks to a reducing atmosphere of methane, ammonia, water, and hydrogen, and the resulting products showed that under these conditions

amino acids can form

A feature that most clearly distinguishes eukaryotes from prokaryotes is the presence of … in eukaryotic cells

a nucleus

Organelles such as mitochondria and chloroplasts are thought to have originated in eukaryotic cells via a process called

endosymbiosis

Which of the following is a colonial organism closely related to the evolutionary precursors of present day plants

Volvox

E. coli is a useful model system for molecular biology because

all the above (it has a small genome, it reproduces rapidly, mutants can easily be isolated from culture dishes)

A yeast cell divides in culture about every

2 hours

The simplicity and clarity of Caenorhabditis elegans allowed researchers to

Trace the developmental lineages of all cells in the adult

Which fish is proving to be a useful model organism for the study of vertebrae development?

zebrafish

Most laboratories make use of cultured cells to study human disease. What makes these cultured cells such useful models?

they provide a continuous and uniform source of new cells

viruses are useful model systems for studying

DNA replication

The light microscope was used to observe the cellular structure of cork by…who named the chambers “cells”

Hooke

Fluorescent-labeled antibodies are used on cells primarily to locate a specific

protein

The method by which cell components are separated by centrifugation at progressively higher speeds is called…centrifugation

differential

Normal human fibroblasts can be grown only for 50-100 doublings in culture, after which they stop growing and die

true

Cytoplasmic organelles are

Absent in prokaryotic cells and present in eukaryotic cells

Mitochondria and chloroplasts resemble bacteria in that they

all of the above (have their own DNA, have their own ribosomes, reproduce by simple division into two, all of the above)

Gregor mendel discovered the principles or genetics in his early experiments on

peas

During formation of eggs and sperm, one member of each chromosome pair is transmitted to each progeny cell in a type of cell division called

Meiosis

DNA was identified as the genetic material in experiments done by

Should be Hershey and Chase but go with Avery, MacLeod, and McCarty

When thymidine and adenosine interact within a DNA molecule, they form

two hydrogen bonds

What is the complementary sequence to the following bases? 5’ - TCAAGG-3’

5’ - CCTTGA - 3’

In Meselson and Stahl’s experiment, cells were grown in media containing 15N in place of 14N and then the cells DNA was separated by equilibrium centrifugation. This experiment demonstrated that DNA

replication is semiconservative

Our fundamental knowledge about mutation, genetic lineage, and the relationships between genes and chromosomes was acquired largely from experiments on the

Fruit fly drosophila

Which of the following deletions will not change the reading frame of a gene

three nucleotides

A codon is a

Sequence of three nucleotides on an mRNA that binds to specific tRNAs

The first enzymatic step in making a cDNA from RNA uses

reverse transcriptase

To identify the protein against which a given sample has an antibody, the best technique to use would be… blotting

Western

All three eukaryotic RNA polymerase are involved in mRNA synthesis

False

Which of the following directly inhibits transcription (RNA synthesis) in prokaryotic systems

Actinomycin D

Immortal cell lines are cells that can continue to proliferate in culture for an indefinite number of generations

True

Yeasts are simple eukaryotes

True

Viruses are complexes of nucleic acid and protein that can replicate on their own

False

Which of the following is a key difference in the origin of replication between prokaryotes and eukaryotes

Eukaryotes have multiple origins, while prokaryotes have a single origin

In which type of organism does DNA replication occur more quickly and why?

Prokaryotes, because they have a smaller genome and simpler replication machinery

What is the primary function of RNA interference (RNAi)

To degrade specific mRNA molecules and reduce protein synthesis

Which of the following correctly describes the differences in the role of primase in prokaryotic and eukaryotic replication?

Eukaryotic primase is part of a complex with DNA polymerase alpha, while prokaryotic primase works independently

Which of the following distinguishes lagging strand synthesis in prokaryotes and eukaryotes

Prokaryotes produce longer Okazaki fragments compared to eukaryotes

What protein is responsible for unwinding the DNA double helix in both prokaryotic and eukaryotic replication

helicase

Who is known as the “Father of Genetics”

Gregor Mendel

Which statement about dominant and recessive traits is correct?

During semiconservative DNA replication, what is the result after one round of replication

An individual with one dominant and one recessive allele will show the dominant phenotype

Which enzyme is responsible for joining DNA fragments together during the construction of a recombinant DNA molecule

DNA ligase

In CRISPR/Cas9 gene editing, what directs the Cas9 enzyme to the specific target DNA sequence

A guide RNA (gRNA)

Which method utilizes a labeled DNA probe to identify specific DNA sequences after electrophoresis

What is the primary function of restriction endonuclease in recombinant DNA technology

southern blotting

What is the significance of alternative splicing in eukaryotic gene expression

It allows a single gene to give rise to multiple mRNA and protein variants

Which of the following statements best describes the structure of most eukaryotic genes

They contain exons interspersed with noncoding introns that are removed during RNA processing

What was the finding from studies using adenovirus as a model for gene expression?

Adenovirus genes are continuous and lack introns

which of the following best describes microRNAs (miRNAs)

They are small noncoding RNAs processed from hairpin structures that regulate gene expression by targeting mRNAs

Which term describes a gene that is entirely located within the boundaries (between the start and stop codons) of a larger host gene?

Nested gene

In the context of noncoding DNA, what is the role of long noncoding RNAs (lncRNAs) such as Xist

They regulate gene expression and, for example, mediate X chromosome inactivation

Which of the following statements distinguishes LINEs from SINEs

LINEs encode reverse transcriptase and integrate into DNA, whereas SINEs are short, do not encode proteins, and rely on LINE-encoded enzymes for transposition

What is a processed pseudogene?

A nonfunctional gene copy created by reverse transcription of an mRNA that is then integrated into the genome

Which of the following is a primary role of transposable elements in the genome

They contribute to genetic diversity and can sometimes lead to gene rearrangements or altered gene expression

Which statement best describes nucleosomes

What unique histone variant is found at centromeres and is crucial for kinetochore assembly

They consist of 147 base pairs of DNA wrapped around a histone octamer, forming the basic unit of chromatin

Which characteristic distinguishes euchromatin from heterochromatin

Telomerase; it adds repetitive sequences to the ends of chromosomes preventing their shortening during replication

How does chromatin condensation change during the cell cycle, and what is its effect on transcription

Chromatin is decondensed during interphase to allow transcription and becomes highly condensed during mitosis where transcription ceases