Test 3 Flashcards
To create nucleotides is sugar (deoxyribose) connected with the phosphate group?
Yes
What are the ways that bases are always connected?
Adenine with thymine, and cytosine with guanine
What is the difference in structure between pyrimidines and purines?
Pyrimidines: single ringed, whereas purines are double ringed
Does the two of them bonding together help form the double helix structure of DNA?
Yes
What are the three parts of a nucleotide?
Sugar, phosphate group, and nitrogenous base
Does the nitrogenous base make a difference of what nucleotide you’re working with?
Yes
Is the backbone of DNA and RNA held together by covalent bonds?
Yes
Which of ATCG are pyrimidines/purines?
Pyrimidines: thymine, and cytosine. Purines: adenine, and guanine.
Do hydrogens bond with different bases?
Yes
Does the antiparallel structure refer to the two strands of DNA?
Yes
What does it mean when it is said that the two strands are antiparallel?
One strand runs in the 5’ to 3’ direction, while the other runs in the 3’ to 5’ direction
Does the 5’ end have a phosphate group attached to the 5’ carbon of the sugar?
Yes
What does the 3’ end have?
A hydroxyl group (-OH) attached to the 3’ carbon of the sugar
What did Griffith’s experiment demonstrate?
Genetic transformation in bacteria
Did he use two strains of streptococcus pneumonia to determine whether there was genetic transformation?
Yes
Was there a smooth but caused disease strain, as well as a rough and did not cause a disease?
Yes
Recall the experiment
S strain and R strain were both given to two different mines. The R-strain one survived whereas the one with the R-strain did not. The S strain was then heated and tested on another mouse, and a mix of the heat killed strain and R strain was given to the mouse given to mouse and died
Did Watson and Crick’s model provide the first accurate understanding of the double helix structure?
Yes
Was Franklin able to take the DNA and identify the double strand model?
Yes
Did the Meselson and Stahl experiment provide definitive evidence that DNA replication is semiconservative?
Yes
What does DNA replication being semiconservative mean?
Each new DNA molecule consists of one old (parental) strand and one newly synthesised one
Did Meselson and Stahl grow strands with medium and isotopes?
Yes
What type of DNA molecules would conservative replication give you?
One DNA molecule would consist of two original strands, and the other would consist of two newly synthesized strands
What is the process of DNA moving to the mRNA called?
Transcription
What is the movement from mRNA to proteins called? What does it use?
Its called translation and uses tRNA and rRNA
Is RNA pulling the double strands apart responsible for transcription?
Yes
Does RNA synthesis begin at the start site of the gene, and RNA polymerase adds RNA nucleotides complementary to the DNA template strand until termination?
Yes
What must ribosomes contain to turn mRNA into protein?
rRNA
What is tRNA responsible for?
Each tRNA enables the translation of a given mRNA codon into a certain amino acid
What is a codon?
A sequence of three consecutive nucleotides in a DNA/RNA that codes for a specific amino acid
For translation to occur does the tRNA bring the appropriate amino acids to the ribosome based on the mRNA’s codons?
Yes
What is the ribosome’s job?
Ensures proper assembly of the growing polypeptide chain until the entire protein is synthesised
What are the two main structures responsible for translation?
Ribosomes, and tRNA
What is the genetic codes?
Set of rules by which the information encoded within DNA or RNA is translated into proteins
What is the promoter?
Region of DNA located at the beginning of the gene which acts as a binding site for RNA polymerase
Who is the father of genetics?
Gregor Mendel
State 5 reasons why peas are used a model for Mendelian genetics
Easy for pollination, really fast to reproduce, ethically acceptable, easy for germination, and easy to see phenotypes
What are the three principles of Mendelian genetics?
Dominant and recessive, segregation, and independent assortment
Do organisms inherit two copies of each gene, one from each parent, with one allele normally being dominant and the other being recessive?
Yes
What is segregation?
When meiosis makes sex cells, each cell has only one allele
What does independent assortment mean?
Each trait is passed on independent of other traits
What is the difference between dominant and recessive?
Dominant is expressed when present, even if there is only one copy. Recessive is only expressed when two copies are present
What does homozygous and heterozygous mean, respectively?
Homozygous: the same alleles, heterozygous: different alleles
What does genotype and phenotype mean, respectively?
Genotype: the genes you have. Phenotype: how those genes are expressed
What does incomplete dominance and codominance mean, respectively?
Incomplete dominance: Neither allele is dominant, and the resulting phenotype is a blend of both traits. Codominance: when both alleles are fully expressed in the phenotype, showing both traits side by side
What does pleiotropy and polygenic inheritance mean, respectively?
Pleiotropy: When one gene affects multiple, unrelated traits in an organism. Polygenic inheritance: when multiple genes work together to influence a single trait
Are ribosomes the sites of translation?
Yes
Does DNA have deoxyribose, and is generally double-stranded?
Yes
Does RNA have ribose, and is generally single-stranded?
Yes
Does the complimentary base pairing make it possible to generate two identical copies of each DNA molecule in a cell preparing to divide?
Yes
What bases are present as pyrimidines and purines respectively?
Pyrimidines (cytosine, thymine, uracil): single six membraned ring, purines (adenine and guanine): six-membered ring fused to a five-membraned ring
How do you form a nucleoside, and nucleotide?
Nucleoside: nitrogenous base + (pentose) sugar, nucleotide: nucleoside + phosphate group
