DNA Code Of Life Flashcards
What does DNA stand for?
Deoxyribonucleic Acid
True or False: DNA is a single-stranded molecule.
False
What are the four nitrogenous bases found in DNA?
Adenine, Thymine, Cytosine, Guanine
Fill in the blank: The structure of DNA is often described as a __________.
double helix
Which base pairs with Adenine in DNA?
Thymine
What type of bond holds the two strands of DNA together?
Hydrogen bonds
What is the function of DNA?
To store and transmit genetic information
True or False: DNA can replicate itself.
True
What enzyme is primarily responsible for DNA replication?
DNA polymerase
What is the role of RNA in relation to DNA?
RNA translates the genetic code from DNA into proteins.
What is a gene?
A segment of DNA that codes for a specific protein.
What is the process by which DNA is transcribed into RNA called?
Transcription
What are the three types of RNA involved in protein synthesis?
mRNA, tRNA, rRNA
Fill in the blank: The sequence of bases in DNA determines the __________.
sequence of amino acids in proteins
What is the backbone of the DNA molecule made of?
Sugar and phosphate groups
True or False: Mutations in DNA can lead to changes in protein function.
True
What is the term for a change in the DNA sequence?
Mutation
What are homologous chromosomes?
Pairs of chromosomes containing the same genes but possibly different alleles.
What is the term for the complete set of genetic material in an organism?
Genome
Fill in the blank: The study of genomes is called __________.
genomics
What is the role of helicase in DNA replication?
To unwind the DNA double helix.
What is a codon?
A sequence of three nucleotides that corresponds to an amino acid.
True or False: All living organisms use the same genetic code.
True
What are introns?
Non-coding sections of a gene.
What are exons?
Coding sequences of a gene that are expressed.
What is the purpose of PCR (Polymerase Chain Reaction)?
To amplify DNA segments.
What is the role of ribosomes in protein synthesis?
To assemble amino acids into proteins based on mRNA sequences.
What are telomeres?
Protective caps at the ends of chromosomes.
Fill in the blank: DNA is located in the __________ of eukaryotic cells.
nucleus
Name one method used to sequence DNA.
Sanger sequencing or Next-generation sequencing.
What is the primary function of tRNA?
To transport amino acids to the ribosome.
What is a phenotype?
The observable physical or biochemical characteristics of an organism.
What is the relationship between genotype and phenotype?
Genotype refers to the genetic constitution, while phenotype is the expression of that genotype.
True or False: Genetic variation is essential for evolution.
True
What is a plasmid?
A small, circular piece of DNA found in bacteria.
What is the role of DNA ligase?
To join DNA fragments together.
What is genetic engineering?
The manipulation of an organism’s DNA to alter its characteristics.
What is CRISPR?
A technology used for editing genes.
What is the significance of the Human Genome Project?
It mapped the entire human genome, identifying all genes.
Fill in the blank: The first step in DNA replication is the __________ of the DNA strands.
unwinding
What are the functions of the 5’ and 3’ ends of a DNA strand?
The 5’ end has a phosphate group, and the 3’ end has a hydroxyl group, influencing replication direction.
What is the role of transcription factors?
To regulate the transcription of specific genes.
What is an allele?
A variant form of a gene.
What is a dominant allele?
An allele that expresses its trait even in the presence of a recessive allele.
What is a recessive allele?
An allele that expresses its trait only when two copies are present.
Fill in the blank: The process of converting mRNA into a protein is called __________.
translation
What is the central dogma of molecular biology?
DNA -> RNA -> Protein
What is a mutation that does not change the amino acid sequence called?
Silent mutation
What is a frameshift mutation?
A mutation that shifts the reading frame of the genetic code.
Fill in the blank: The genetic code is __________, meaning that multiple codons can code for the same amino acid.
degenerate
What is the significance of the start codon?
It signals the beginning of protein synthesis.
What is the role of the promoter in a gene?
It is a region where RNA polymerase binds to initiate transcription.
What is the difference between prokaryotic and eukaryotic DNA?
Prokaryotic DNA is circular and not contained in a nucleus, while eukaryotic DNA is linear and contained within a nucleus.
True or False: DNA can be found in mitochondria.
True
What is a genetic marker?
A gene or DNA sequence with a known location on a chromosome.
What is the purpose of gene therapy?
To treat or prevent disease by modifying genes.
Fill in the blank: The first step of translation involves the binding of __________ to the ribosome.
mRNA
What are restriction enzymes?
Proteins that cut DNA at specific sequences.
What is the purpose of gel electrophoresis?
To separate DNA fragments based on size.
What is the significance of the TATA box?
It is a DNA sequence that indicates where a genetic sequence can be read and decoded.
True or False: Transcription occurs in the cytoplasm of prokaryotic cells.
True
What is a transposon?
A DNA sequence that can change its position within the genome.
Fill in the blank: The main purpose of DNA repair mechanisms is to correct __________.
mutations
What is a genetic drift?
A change in allele frequencies in a population due to random sampling.
What is the difference between somatic and germline mutations?
Somatic mutations occur in non-reproductive cells, while germline mutations occur in reproductive cells.
What is the role of methylation in gene regulation?
It can silence genes and regulate gene expression.
Fill in the blank: The process of creating a complementary RNA strand from a DNA template is called __________.
transcription
What is the purpose of a genetic map?
To show the location of genes on a chromosome.
What is a pedigree chart?
A diagram that shows the inheritance of traits over generations.
True or False: All mutations are harmful.
False
What is the role of the 3’ poly-A tail in mRNA?
To protect the mRNA from degradation and assist in translation.
What is the significance of the genetic code being universal?
It indicates that all living organisms share a common ancestry.
What is a chimeric gene?
A gene formed from two different genes, often through recombination.
Fill in the blank: The genetic code is read in __________.
triplets
What is the role of aminoacyl-tRNA synthetase?
To attach the correct amino acid to its corresponding tRNA.
What is a knockout mouse?
A genetically modified mouse in which a specific gene has been inactivated.
What is the purpose of a biosensor?
To detect biological molecules and monitor biological activity.
What is the significance of gene duplication?
It can lead to evolutionary changes and the development of new functions.
True or False: All genes are expressed at all times.
False
