micro HW week 5 review

Phase variation is a phenomenon used by some bacteria (such as E. coli) to evade host immune mechanisms. In this process, the cells

alternately turn genes on/off to adjust bacterial behavior

Changing your T-shirt for one of a different color is analogous to

antigenic variation

the 2 strands of the DNA molecule are

are antiparallel: one running 5' to 3', the other running from 3' to 5'. This impacts the process of DNA replication.

Removing the electron transport chain of E. coli would

prevent oxidative phosphorylation

The processes of transcription and translation differ between prokaryotes and eukaryotes in the following way:

prokaryotes transcribe and translate simultaneously; (Since they lack a nucleus and mRNA processing is not required)

ETC is part of

respiration

Protein synthesis occurs on the ____.

ribosomes

After mRNA is made, what generally occurs?

the mRNA is translated to protein

in bacteria, the ETC is located in

the plasma membrane

The process of transcription is similar to:

the synthesis of the leading strand during DNA replication

In aerobic respiration, oxygen acts as

the terminal electron acceptor

The energy captured in the phosphorylation of ADP to ATP comes from the proton motive force created in respiration True or false?

true

anabolic processes

use energy from ATP to drive synthesis of molecules used to make up cell structures

a mechanism that blocks transcription

will block the production of mRNA

Why would an organism use fermentation to generate ATP?

-The organism lacks an electron transport chain -A suitable inorganic terminal electron acceptor is not available.

Which of the following statements accurately describe biochemical pathways?

-They convert an initial substrate through a series of steps into an end product. -They are well-organized and structured. -they are carefully regulated -They can be linear, branched, or cyclical

After the completion of DNA replication in prokaryotic cells,

-each daughter cell contains DNA with one newly synthesized DNA strand and one original parental strand. -both daughter cells have identical copies of DNA

If a 75 base-pair fragment of DNA has 25 cytosines in it, how many adenines would you expect it to have?

50

During the electron transport chain, ATP will be made from

ADP + Pi

Consider the biochemical pathway: A → B → C Enzyme 1 catalyzes A → B Enzyme 2 catalyzes B → C If enzyme 2 is inactive, which of the following compounds will accumulate?

B only

You are studying the metabolism of the phototrophic green sulfur bacterium Chlorobaculum tepidum and realize that it is running a reversed TCA cycle! How do you explain this observation?

C. tepidum is using the reversed TCA cycle to fix carbon dioxide.

What type of molecule(s) could the following be? AGCGCCGCAACGC

DNA RNA

direction genetic information flows

DNA --> RNA--> protein

Hydrogens are transported from other reactions to the ETC by

NADH and FADH2

true or false only eukaryotic mRNA is processed before translation

True

3 basic parts of a nucleotide

a phosphate, deoxyribose sugar, and nitrogenous base. All of these play a role in DNA replication

in absense of lactose, the lac repressor is

active and can bind to the operator.

which contains a metal ion which can accept and donate electrons?

cytochromes

One advantage of having genetic control mechanisms is:

efficiency: enzymes are only produced when they are needed

treptococcus pneumoniae lacks an electron transport chain. Therefore, S. pneumoniae generates ATP via _________.

fermentation

In the electron transport chain, protons are pumped across the cell membrane. This results in

formation of a proton motive force

A segment of DNA encoding a protein or an RNA molecule is a ________

gene

the lac operon is expressed when

glucose is low and lactose is present

The breakdown products of proteins can enter which of the following metabolic pathways?

glycolysis TCA cycle pentose phosphate pathway

catabolic processes

harvest energy released from the breakdown of compounds to make ATP

2 stands of DNA are joined to each other or held together by

hydrogen bonding

where does translation of eukaryotic mRNA occur

in the cyctoplasm

A fundamental aspect of gene regulation lies in the _________ of mRNA molecules. Because of this trait, these molecules won't remain in the cell long after transcription has been turned off by the cell, regulating gene expression.

instability

If a protein-encoding gene contains introns and exons, it is likely that

its a eukaryotic gene

In bacteria, proton pumps are protein complexes that

move proteins from the interior of the cell to the exterior

RNA is a chain of

nucleotides

Consider the biochemical pathway: A → B → C Enzyme 1 catalyzes A → B Enzyme 2 catalyzes B → C Enzyme 1 can utilize

only A as a substrate

DNA polymerase can

only add nucleotides in one direction, and therefore, one strand is synthesized continuously from the origin of replication and the other is synthesized as short fragments.

Coordinated sets of genes that are regulated as a single unit are referred to as ______.

operons

What component of RNA is different from one individual (or one bacterium) to the next?

order of nitrogenous base (like DNA, the sequence of the bases is what makes each strand unique)

The bond connecting amino acids is a ____ bond.

peptide bond

A __________ is the physical expression of the genes present and can change depending upon what genes are turned "on".

phenotype

3 components of RNA structure

phosphate group, a nitrogenous base (AUCG) and a ribose sugar.