Micro Learnsmart Ch. 8
In conjugation, a copy of the DNA being transferred is retained by the donor, and this is termed a ___________ process
conservative
Transcription occurs in the ____________ of bacteria and the ____________ of yeast cells
cytoplasm; nucleus
According to the rules of complementary base pairing, the nitrogenous base _____________ forms hydrogen bonds with guanine
cytosine
_______________ is the pentose sugar in DNA
deoxyribose
In eukaryotic genes, introns are interspersed between coding regions called _________, that will be translated into protein
exons
Which two components of a nucleotide are bound to form the backbone of a DNA strand?
Deoxyribose sugar and phosphate
Viral genomes are composed of...
Either DNA or RNA
Which organic molecule is formed from chains of amino acids that are produced in translation?
Protein
Which is the main event of transcription initiation?
RNA polymerase binds the DNA promoter
True or False: Only viruses can have an RNA genome
True
True or false: Ribose is the pentose sugar in RNA
True
The start codon AUG is associated with the tRNA anticodon ______________ and the amino acid ____________
UAC; fMet
Which of the following nitrogenous bases is found in both DNA and RNA?
adenine
tRNA carries a ________ to the ribosome during protein synthesis
amino acid
During translation elongation, peptide bonds form between...
amino acids
In DNA, the two strands of the helix are arranged in a(n) _____________ arrangement.
antiparallel
A(n) ___________ is a sequence of DNA nucleotides that codes for a group of related proteins
gene
The science of heredity is...
genetics
The complete set of chromosomes and genes in an organism is referred to as the...
genome
The term ___________ refers to all the genes constituting an organism's distinctive genetic makeup, the expression of which results in the organism's phenotype
genotype
A sequence of DNA in a eukaryotic gene that does not code for protein is called a(n)
intron
Which type of RNA is a copy of the DNA template corresponding to a protein-encoding gene?
mRNA
During transcription elongation, RNA polymerase synthesizes a strand of ___________ from template ________________
mRNA; DNA
A change in the genetic code that leads to the insertion of a different amino acid in a protein is called a ______________ mutation
missense
A mutation that does not lead to adverse or helpful changes is termed a __________ mutation
neutral
A nitrogen-containing molecule found in DNA and RNA that provides the basis for the genetic code is a(n):
nitrogenous base
In a protozoal or fungal cell, chromosomes are located in the...
nucleus
E. coli and other bacteria typically have ________________ chromosomes
one
What are the three components of a DNA nucleotide?
phosphate, deoxyribose sugar, and nitrogenous base
DNA _________ must occur prior to cell division to ensure that each new cell has a complete genome
replication
Two subunits of the _______________ comprise the site of protein synthesis
ribosome
rRNA composes _____ subunits together with protein
ribosome
The ______________ is an RNA-protein complex that recognizes exon-intron junctions and excises introns from an mRNA transcript in eukaryotes
spliceosome
The three basic categories of genes are regulatory genes that control gene expression, genes that code for the RNA machinery used in protein production, and ______________ genes that code for proteins
structural
Which kind of gene encodes a protein?
structural
Which RNA forms into hairpin loops?
tRNA
The process of transcription ________________ results in the release of a completed RNA transcript
termination
The expression of the genotype creates traits referred to as...
the phenotype
A codon contains how many nucleotides?
three
The assembly of the ribosome and the locating of the AUG start codon are events that initiate the process of...
translation
____________ is the process of decoding the messenger RNA into a polypeptide
translation
What is the complementary DNA sequence to the DNA template 3'-ATACTAAAATTT-5'?
5'-TATGATTTTAAA-3'
The anticodon of the tRNA carrying the codon GUU is ______________
CAA
Genomes of cells are composed of...
DNA
What is the central theme of molecular biology?
DNA encodes RNA which encodes protein
________________ _____________ is the enzyme that transcribes DNA into RNA
DNA polymerase
Junk DNA is...
DNA whose function is not yet understood
RNA polymerase converts _____________ into the various types of _______________
DNA; RNA
How do the chromosomes of bacteria and eukaryotes differ?
Eukaryotes have histones but bacteria have histone-like proteins and Eukaryotes are located in the nucleus but bacteria chromosomes are not in a membrane-bound organelle
True or False: A typical bacterial chromosome consists of several thousand nucleotides
False
True or False: Eukaryotic chromosomes are composed of DNA and RNA
False
What are the differences between eukaryotic and bacterial protein synthesis?
The first amino acid is slightly different and transcription and translation are simultaneous in bacteria but not eukaryotes
When UAA, UAG, or UGA is encountered on the mRNA transcript, translation...
ends
Where are bacterial chromosomes located?
in the nucleoid region of the cytoplasm
____________ and proteins compose ribosome subunits
rRNA
________________ is the process of decoding DNA into messenger RNA
transcription
What are the three major types of RNA
transfer, messenger, and ribosomal
The pyrimidine nitrogenous bases found in RNA are cytosine and _____________
uracil
Unlike DNA, RNA contains the nitrogenous base _______________
uracil