Final Exam part 1 Flashcards
What is the nature of science?
to ask questions that can be answered by observing or measuring things
What are the dependent and independent variable on a graph?
independent- x-axis
dependent- y-axis
what are the steps of the scientific method?
observation/question, research topic area, hypothesis, test with an experiment, analyze data, report conclusions, repeat…
What is a hypothesis?
a proposed explanation based on limited evidence and used as the starting point for developing an experiment. Should be precise and testable
What is a null hypothesis and what is its purpose?
It states that the hypothesis is not the explanation. It makes the scientist be able to see if the data collected was by random chance or not
What is the control of an experiment?
It is the basis for which comparisons are made during an experiment, the group left unchanged.
What is DNA?
Deoxyribonucleic acid
What stores the genetic information in cells?
DNA
What is a nucleic acid?
a polymer made up of monomers called nucleotides
What was the Hershey-Chase experiment?
An experiment that determined that DNA stores genetic material, not proteins as previously thought
What do T2 proteins contain (used in the Hershey-Chase experiment)?
sulfur
What does DNA contain (used in the Hershey-chase experiment)?
phosphorous
What is a polymer?
a substance consisting of repeating subunits (monomers)
What is a nucleotide?
a phosphate group bonded to a 5carbon sugar which is bonded to a nitrogenous base
What are the single-ring nitrogenous bases?
cytosine, uracil, and thymine
What are the double-ringed nitrogenous bases?
guanine and adenine
What is the primary structure of DNA?
a directional sugar-phosphate backbone
What is the secondary structure of DNA?
an anti-parallel double helix
What was the Watson & Crick experiment?
discovered the sugar-phosphate backbone of DNA, and discovered the rules of nitrogenous base pairings
What did Rosalind Franklin and Maurice Wilkins do?
Used x-ray crystallography to determine that DNA has a helical shape
What is complementary base pairing?
adenine to thymine, guanine to cytosine
Where is DNA found in eukaryotes?
chromosomes
What is DNA replication?
Using the genetic code of DNA to synthesize new DNA
DNA replication is ______
semi-conservative
What is meant by DNA replication is semi-conservative?
parental strands separate, and each are used as a template strand for a new daughter strand
What are the steps of DNA replication?
- replication bubble forms at the origin of replication
- DNA synthesis proceeds in the 5’ to 3’ direction, adding nucleotides at the 3’ end
- Active DNA synthesis takes place at the replication forks of the bubble
- synthesis occurs on both strands of the template DNA at the replication forks
What direction does DNA synthesis occur in the leading strand?
5’ to 3’ or towards the replication fork
What direction does DNA synthesis occur in the lagging strand?
3’ to 5’ or away from the replication fork
What is the central dogma?
DNA (transcription) mRNA (translation) proteins
What happens during transcription?
RNA polymerase uses a template DNA strand to a complementary nucleotide to the growing mRNA strand in the 5’ to 3’ direction (adds to the 3’ end)
Is mRNA single or double stranded?
single
What is translation?
The use of mRNA as a genetic code to produce protein
What is the genetic code?
The coding for amino acids produced when 3 base pair triplets are read
What are codons?
3 base pair triplets
What is the start codon?
AUG
What are the features of the genetic code?
It is redundant, unambiguous, non-overlapping, (nearly) universal, and conservative
What is a gene?
A section of DNA which codes for a protein
What are chromosomes?
Organized DNA that are made of a single long DNA double helix wrapped around histone proteins
What is a chromatin?
Complex of DNA which codes for a protein
What is a locus?
The physical location of a gene on a chromosome
What is an unreplicated chromosome?
A single, long DNA double helix wrapped around histone proteins
What is a replicated chromosome?
Consists of two copies of the same DNA double helix
What is a diploid cell?
A cell containing two sets of chromosomes
What is a haploid cell?
A cell containing one set of chromosomes
What are alleles?
Different versions of the same gene
What is gene expression?
Set of processes that converts the information in DNA into the product of a gene
What is a genotype?
The alleles of a gene present within a single organism
What is the one gene - one polypeptide hypothesis?
each gene contains information to produce one protein
What is a phenotype?
A detectable trait of an organism
What is an important exception to the central dogma?
Many genes code for RNA’s that function directly in the cell
What does heterozygous mean?
Containing two different alleles of the same gene
What does homozygous mean?
Containing two of the same alleles of the same gene