The animal extracellular matrix contains what in comparison to plant ECM?
more protein in comparison to carbohydrate
both collagen and protein
both collagen and microfibrils
Desmosomes are a cell-cell attachment mostly commonly found in which of the following animal cells?
nerve and muscle cells
epithelial and muscle cells
Which of the following is NOT part of a desmosome?
attaches the plasma membrane of adjacent cells
has membrane proteins that link cells
has intermediate filaments
has plasmodesmata that connect cytoplasm of adjacent cells
Which of the following is NOT a lipid-soluble signaling molecule?
all choices are lipid soluble
In order for a G protein to be activated, what needs to occur?
ADP needs to become ATP
ATP needs to transfer energy to GDP
GDP becomes GTP
GTP becomes GDP
Which of the following is NOT a second messenger?
Which of the following demonstrates the mechanics of G-Protein-Coupled Receptors
G protein remains inactive when bound to GTP
G protein remains inactive when bound to GDP
G protein splits into two parts when activated
A second messenger triggers a response when bound to the signal receptor
Where are the protein components of the extracellular matrix synthesized?
in the rough ER
in the Golgi apparatus
in the plasma membrane
in the extracellular layer itself
[blank_start]Lipid-soluble[blank_end] signaling molecules often pass through the plasma membrane and bind to cytosolic signal receptors. Signaling molecules that are [blank_start]not lipid soluble[blank_end] often bind to signal receptors in the plasma membrane.
One unique feature of lipid soluble signaling molecules are their ability to
behave as transcription factors
use a signal transduction system
act as kinases
both behave as transcription factors and act as kinases
both use a signal transduction system and act as kinases
The connecting of cytoskeletons between adjacent cells in animal tissues is accomplished using
The use of signal transduction systems enables cells to
activate and/or deactivate specific cellular activities
control gene expression
amplify cellular responses
activate/deactivate specific cellular activities and control gene expression
all choices would apply
Who discovered the secondary structure of DNA?
Hershey and Chase
Watson and Crick
Stahl and Meselson
Hershey and Crick
Which of the following images depicts semiconservative replication?
How many origins of replication do eukaryotic chromosomes have?
What is the primary responsibility of SSBPs?
relieves twisting forces of helicase
open the double helix
prevent the rebinding of separate strands of DNA
final linking process of DNA nucleotides
Which is true of telomerase?
contains its own RNA template
works in the synthesis of RNA
works in the synthesis of DNA
contains its own DNA template
Which of the following types of repair occurs after DNA synthesis is complete?
nucleotide excision repair
just mismatch and nucleotide excision repair
all of the choices are correct
Synthesis of the [blank_start]leading strand[blank_end] is continuous, but synthesis of the [blank_start]lagging strand[blank_end] is discontinuous because on that strand, the DNA polymerase moves away from the replication fork.
Which of the following is NOT a property of DNA polymerase?
it adds dNTPs only in the 5' --> 3' direction
it requires a primer to work
it is associated with a sliding clamp only on the leading strand
its exonuclease activity is involved in proofreading
How are Okazaki fragments synthesized?
using the leading strand template, and synthesizing 5' --> 3'
using the leading strand template, and synthesizing 3' --> 5'
using the lagging strand template, and synthesizing 5' --> 3'
using the lagging strand template, and synthesizing 3' --> 5'
The enzyme involved in adding new nucleotides to the leading and lagging strands of DNA during replication could be
DNA polymerase I
Multiple RNA primers and fragments of DNA during DNA replication would be characteristic of
the lagging strand of DNA
the replication fork
the leading strand of DNA
mtDNA has the following characteristics
comes only from the mother
the haploid number of chromosomes
the diploid number of chromosomes
none of the above
Which of the following is the central dogma of biology?
DNA --> RNA ---> mtDNA
DNA ---> RNA ---> proteins
RNA ---> proteins ---> DNA
proteins ---> RNA ---> DNA
Which of the following is NOT an example of a genotype?
one heterozygous allele, one homozygous allele
none of the choice are representative of a genotype
Which of the following is the universal start codon?
What are the three stop codons that signal that the end of translation?
UAA, UGA, UAG
AAU, GUA, UGA
AAA, GUA, UAA
none of the choices are correct
Which of the following is not true about the genetic code?
The code is redundant
The code is ambiguous
The code is non-overlapping
The code is nearly universal
Which of the following point mutation are most likely to be deleterious?
silent, missense, frameshift
missense, nonsense, frameshift
frameshift, nonsense silent
The two purine bases in the DNA are
adenine and thymine
adenine and guanine
cytosine and guanine
thymine and cytosine
A codon would contain
Point mutations that alter the meaning of subsequent codons are called
What must bind to bacterial RNA polymerase before transcription can begin?
Why do NTPs have a significant amount of potential energy?
because of its one phosphate group
because of its two phosphate groups
because of its three phosphate groups
Which of the following are part of eukaryotic RNA processing?
addition of 5' cap on mRNAs
addition of 3' poly (A) tail
addition of promoter that contains -35 and -10 box
addition of 3' poly (A) tail and 5' cap
addition of promoter and 3' poly (A) tail
What is removed from eukaryotic RNA transcripts?
both are removed
some of each are removed
The secondary structure of tRNA resembles...
there is no such thing as secondary structure of tRNA
Which is the correct sequence of the elongation of translation?
First: incoming aminoacyl tRNA, Second: A site becomes empty, Third: peptide bond is formed between tRNA in P and A site.
First: incoming aminoacyl tRNA, Second: peptide bond is formed between tRNA in P and A site, Third: A site becomes empty
First: A site becomes empty, Second: Peptide bond is formed between tRNA in A and P site, Third: incoming aminoacyl tRNA
Which of the following does NOT take place in the nucleus of a eukaryotic cell?
Translation initiation occurs when...
the ribosome binding site on an mRNA bind to an rRNA sequence in the small ribosomal subunit
the initiator aminoacyl tRNA binds to the start codon in the mRNA
the large subunit of the ribosome attaches to the small subunit
all choices are correct
What does a bacterial RNA polymerase produce when it transcribe a protein-coding gene?
Temperature-sensitive conditional mutations cause expression of a wild-type phenotype at one growth temperature and a mutant phenotype at another -typically higher- temperature. Imagine that when a bacterial cell carrying such a mutation is shifted from low to high growth temperatures, RNA polymerases in the process of elongation complete transcription normally, but no new transcripts can be started. The mutation in this strain most likely effects which feature?
the terminator sequence
the start codon
one of the polypeptides at the core RNA polymerase
Which enzymes link the correct amino acid to the correct tRNA?
The information used in translation to a peptide, specifying which codon codes for which amino acid is carried by
aminoacyl tRNA synthases
Destruction of an mRNA in the cytoplasm prior to reaching a ribosome would be considered a
post transcriptional process
both pre translational and pre transcriptional process
both pre translational and post transcriptional process
In [blank_start]eukaryotes[blank_end], transcription and translation of an RNA cannot occur together because transcription occurs in the nucleus and translation occurs in the cytoplasm.
Any technique for picking particular types of mutants out of many randomly generated mutants is known as...
What holds DNA polymerase in place during strand extension?
an exterior protein coat as seen in Hershey and Chase's experiment is known as