Chapter 10 Flashcards
What is molecule biology?
the scientific study of life at the molecular level
An understanding of molecular biology may enable us to identify the function and nature of
Disease, bacteria, viruses
DNA, genes, inheritance
cancer
_____ is a molecule that stores the information to create and organism (The Blueprint)
DNA
Information stored in DNA can be ______ and _____passed on to the next generation.
copied and passed
What two type of nucleic acids can store genetic information?
DNA and RNA (ribonucleic acid)
DNA and RNA consist of monomers called ________.
nucleotides
Nucleotides are composed of three components.
Sugar, phosphate group, and a nitrogenous base.
The sugar and the phosphate group form a strong support structure for the nitrogenous base known as.
The sugar-phosphate backbone.
Nucleotides in DNA include?
Adenine (A), Guanine (G), Cyosine (C), Thymine (T)
Nucleotides in RNA include?
Adenine (A), Guanine (G), Cyosine (C), Uracil (U)
Purines
Adenine, Guanine
Pyrimidines
Cytosine (C) Uracil (U), Thymine (T)
X-Ray cystallography data collected determined that DNA is a double helix
Roselind Frankin and maurice Wilkins, James Watson and Francis crick
Nitrogenous bases pair according to strict rules
A pairs with T and C pairs with G
During the cell cycle, a cell’s DNA has to be copied completely so each new cell will have a complete set of DNA in the form of ____________.
Chromosomes
Each of the two original DNA strands serves as a template based oh which two new stands of DNA are made by enzyme ______________.
DNA polymerase
What is DNA replication?
One of the original two DNA strands is passed on to each of the new cells
How is DNA synthesized?
using the parent strand as a template
DNA replication spreads from specific origin
is bidirectional, adding nucleotides in each direction
Once DNA replication is completed it produces
Two daughter strands
The ___ of an organism (its genotype) is what controls how the organism looks and functions (its phenotype)
DNA
From one generation to the next, DNA is continually _______and _______down.
replicated and passed down
Because DNA is copied, passed down, then inherited during fertilization, we should have similar sequences of __________ in our genes as our parents.
Nucleotides
DNA is a set of stored sets of instructions (genes) to make ______.
proteins
By __________RNA is generated from DNA from complementary base pairing.
Transcription
RNA is an ___________ to create protein.
Intermediate step
RNA is then _________ into proteins.
Translated
There are about _______ genes in the human genome, each of which _______specific protein.
30,000
encodes
Not all proteins are produced all the time in all cells;
DNA is transcribed 1 gene at a time
The sequence of nucleotides in DNA and RNA determines the sequence of ______ in a protein.
Amino acid
How can each protein differ?
By their length, type of amino acid present or squence of amino acid
When DNA is transcribed
an RNA molecule is produced
After DNA is transcribed into an RNA molecule is produced the RNA molecule can then be translated into a sequence of ___________________________.
amino acids to make protein
3 consecutive RNA nucleotides is called?
Codon
One codon codes for one of ____ amino acids.
20
the information contained in one gene is used to as a template to make one ______________
RAN molecules
RAN sequences represent one gene of _____.
DNA
The enzymes _________________ is the enzyme which synthesizes RAN from DNA
RAN polymerase
RAN polymerase
It finds the starting and stopping points of the gene and it attaches RNA nucleotides in the correct order to make the RNA molecules
RAN nucleotides are brought in by RNA polymerase, then complementary base pair with DNA. this continues forming an RAN molecule from a DNA template. So,
the sequence of DNA determines the sequence of RNA!
The first phase of transcription is _________.
initiation
to begin transcription, RNA polymerase must detect a start sequence called____________
promoter
When the enzyme encounters a promoter sequence, it becomes attached to the __________.
DNA strand
this attachment must occur before RNA can be _______________. from DNA
tramscribed
The second phase of transcription is _________________.
elongation
During elongation, more and more nucleotides are attached to the growing RNA molecule, representing an ______________.
entire gene
The third phase of transcription is ______________.
termination
Near the end of each gene is a sequence of bases called a _____________________.
terminator sequence
When the RNA polymerase reaches a terminator, it is stimulated to detach from the DNA template, and RNA synthesis stops ending transcription. This RNa is then processed into messenger RNA or mRNA by a process called ______________.
splicing
After an RNA transcript is generated from a DNA template, the RNA transcript is prepared for translation in a process called _____________.
splicing
The introns are edited out, and exons are spliced together. ____________________________.
This converts RNA into mRNA
During translation, the set of instructions on an RNA molecule is converted to an ____________ sequence.
Amino acid
Just as transcription was facilitated by an ______, translation requires the presence of other _______.
Enzyme
Molecules
What additional RNA molecules are needed to facilitate translation?
tRNA (transfer RNA)
rRNA (ribosomal RNA aka ribosomes)
tRNA brings amino acids to the ______.
mRNA
__________are 3 consecutive tRNA nucleotides which H-bond to corresponding mRNA condons
Anitcodons
each anticondon carriers with it __ amino acid
1
____________ are small organelles
ribosomes
Ribosomes are the site where amino acids are joined, and proteins _________ are made
precursor
Each ribosomes has _____________.
two subunits
Ribosomes are made from ______________.
ribosomal RNA (tRNA)
Translation has three phases what they?
initiation,elongation and termination
mRNA molecules have a ____ and ____ to help bind the ribosomal sununit.
cap and tail
What is the process of initiation?
mRna binds to the small ribosomal subunit, then an initiator tRNA anticondon molecule binds to the start condon (AUG) bringing with it Methionine (met)
Codon recognition
Subsequent mRNA codons attract incoming tRNA anitcodons in proper sequence. (in sets of 3 nucleotides per amino acid)
Peptide bond formation
The tibosome act as a catalyst and connects the growing amino acid tail with amino acid on the incoming tRNA
Translocation
empty tRNAs are released from the ribosome, incoming tRNA switch places, and the mRNA moves down one codon
_____ are recharged with amino acids using ATP
tRNA
What is the process of elongation
anticodons from tRNA bind with codons on mRNA in
codon recognition
peptide bond formation
translation
Elongation continues until the ribosome reaches a _________.
Stop codon
_______ have no corresponding tRNA, so the ribosome disassembles, leaving a strand of amino acids joined together by peptide bonds
Stop codon
a mutation is a permanent change in the _____________________________.
nucleotide sequence of DNA
Mutations, especially in the __ or ___ base in a codon may change the amino acid sequence of a protein
1st
2nd
Mutations within a gene can be divided into two general categoires which are.
Single base substitution can alter 1 amino acid in a protien
insertions and deletions of nucleotide can cause a change in the entire reading frame
__________ sources that cause mutation
Mutagens
Although mutation are usuaaly always harmful to an organism, they are considered a driving force of _______________________.
diversity and variation
Viruses?
have some characteristics of living organisms
they are not considered living because they lack certain cellular mechanism such as growth
viruses can affect plants, animals and bacteria
Viruses that attack bacteria are called _________.
bacteriophages
lytic
cell explodes releasing more (lyses) virues
lysogenic
inserts there dna intp bacteria dna causing it to replicate with normal cells
HIV is a _______, an RNA virus that reproduces by means of a DNA molecules
Retrovirus
Retro virus copy their RNA to DNA using the enzyme _____________.
reverse transcripition
