w1 slides fc Flashcards
origins of mitochondria and chloroplast
-archaea may have expanded and closed in on aerobic bacterium
-believed that photosynthetic bacteria was engulfed the same way
-evolved into chloroplast
tRNA structure importance
important for function
rRNA
does the catalytic work of making protein
makes peptide bonds
plays structural role as well
transcriptome
all the RNA in cell at a time
-changes (dynamic)
proteome
entire set of proteins at a time
-also changes constantly (dynamic)
phenome
observable characteristics of a cell or organism
interactome
feed info to metabolome
-all proteins interact here + dynamic
-gives info to RNA (e.g. ATP, sugars)
metabolome
full set of small molecules found in cell
-dynamic
-affects genome, transcriptome, proteome
DNA, RNA and proteins are synthesized as:
(start as) linear chains of info with a definite polarity (directionality–>built w/ monomers and subunits)
acronym for purines/pyrimidines
pyrimidines–> U C The pyramid (U,C,T)
purines–> pure things Are Good
how to number sugars
prime(‘)=carbon
base gets attached at 1’
nucleoside monophosphate
sugar + base + 1P
nucleoside diphosphate
sugar base and 2P
nucleoside triphosphate
sugar base and 3P
dna is synthesized from
deoxyribonucleoside triphosphates aka dNTPs (A, C, T or G)
rna is synthesized from
ribonucleoside triphosphates aka NTPs (A, C, U, G)
nucleoside vs nucleotide
SIDE= w/o phosphate
TIDE= w/ phosphate
electrostatic attractions
strong in absence of water
-weak when cells are in water
-ionic bonds
–attraction b/w oppositely charged molecules within + b/w large molecules
hydrogen bonds
-strongest in straight line
-weaker than covalent bonds
-important for structure
van der Waals attractions
-multiple are strong tg
-weakest when 2 atoms close tg and there’s fluctuation in distribution of atoms
hydrophobic force
-pushes non-polar away
-not attracted to water
-pushes bases (polar) out of water
what are the 2 ends of the DNA strand composed of?
5’ = phosphate group (-PO4)
3’= hydroxyl group (OH)
What is one reason why eukaryotic cells can be larger than prokaryotic cells?
(A) They lack a nucleus.
(B) They have internal membrane-bound organelles.
(C) Their DNA is circular.
(D) They divide through binary fission.
b
Which of the following is NOT evidence for the Endosymbiotic Hypothesis?
(A) Mitochondria have their own DNA.
(B) Mitochondria and chloroplasts replicate independently from the nucleus.
(C) Mitochondria and chloroplasts have a double membrane.
(D) Mitochondria have linear chromosomes like eukaryotes.
d
Which of the following was the host cell in the Endosymbiotic Theory?
(A) Aerobic bacterium
(B) Anaerobic archaeon
(C) Cyanobacterium
(D) Fungal cell
b
Which of the following is NOT a characteristic of a good model organism?
(A) Large body size
(B) Short life cycle
(C) Ease of genetic manipulation
(D) Well-understood genetics
a
Why do scientists use model organisms in research?
(A) They are genetically identical to humans.
(B) They allow for controlled experiments and genetic studies.
(C) They are more complex than humans.
(D) They are immune to mutations.
b
Which of the following correctly represents the flow of genetic information?
(A) RNA → DNA → Protein
(B) DNA → Protein → RNA
(C) Protein → RNA → DNA
(D) DNA → RNA → Protein
d
Which molecule is directly involved in transcription?
(A) DNA Polymerase
(B) Ribosome
(C) RNA Polymerase
(D) tRNA
c
Which type of RNA carries the genetic code from DNA to ribosomes?
(A) mRNA
(B) tRNA
(C) rRNA
(D) miRNA
a
What is the function of tRNA?
(A) It catalyzes transcription.
(B) It carries amino acids to the ribosome.
(C) It serves as a structural component of the ribosome.
(D) It copies DNA into RNA.
b
Which bond type is responsible for base pairing in DNA?
(A) Hydrogen
(B) Covalent
(C) Ionic
(D) Peptide
a
What force contributes to the stability of the DNA double helix by keeping bases stacked?
(A) van der Waals interactions
(B) Ionic bonds
(C) Disulfide bonds
(D) Covalent bonding
a
Which of the following forces is NOT involved in maintaining DNA structure?
(A) Hydrogen bonding
(B) Hydrophobic interactions
(C) Disulfide bonding
(D) van der Waals forces
c
Which of the following statements about the Endosymbiotic Theory and Central Dogma is correct?
(A) The mitochondrial genome encodes all the proteins needed for its function.
(B) Mitochondria replicate independently but still require nuclear-encoded proteins.
(C) Mitochondria use ribosomes identical to those found in eukaryotic cytoplasm.
(D) The nuclear genome controls mitochondrial replication via direct transcription of mitochondrial genes.
b
Which of the following correctly describes a key difference between bacterial transcription and eukaryotic transcription?
(A) Bacterial transcription occurs in the cytoplasm, while eukaryotic transcription occurs in the nucleus.
(B) Bacteria require multiple RNA polymerases, whereas eukaryotes use only one.
(C) Eukaryotic transcription is coupled with translation, whereas bacterial transcription occurs separately.
(D) Only eukaryotes use a ribosome to translate mRNA into proteins.
a
What structural characteristic of nucleic acids explains their ability to store and transfer genetic information?
(A) The sugar-phosphate backbone provides structural stability, while base-pairing allows for complementary copying.
(B) The nitrogenous bases are covalently bonded, preventing sequence changes.
(C) The 5’ to 3’ polarity ensures RNA and DNA molecules have the same sequence.
(D) The ability to store information depends only on hydrogen bonding between bases.
a
Which of the following best explains why DNA replication and transcription require different enzymes?
(A) Transcription requires helicase, but DNA replication does not.
(B) DNA polymerase requires a template, whereas RNA polymerase does not.
(C) RNA polymerase only functions in eukaryotes, while DNA polymerase functions in both prokaryotes and eukaryotes.
(D) DNA polymerase synthesizes a double-stranded product, while RNA polymerase synthesizes a single-stranded product.
d
Which of the following best describes how the structure of ribosomal RNA (rRNA) supports its function?
(A) Its linear structure allows for rapid degradation when translation is complete.
(B) Its catalytic properties enable peptide bond formation in translation.
(C) Its hydrogen bonding ensures that only a single protein can be translated at a time.
(D) Its 3D structure prevents ribosomal subunits from interacting with mRNA.
b
Why do model organisms provide insight into human cellular function?
(A) They share common ancestors and many fundamental biological processes with humans.
(B) Their genes are identical to human genes.
(C) Model organisms cannot undergo mutations, ensuring perfect experimental results.
(D) Humans evolved directly from prokaryotic model organisms like E. coli.
a
Which type of macromolecule interactions would be disrupted if a cell was placed in a nonpolar solvent?
(A) Hydrogen bonding in DNA base pairs
(B) Hydrophobic interactions within lipid membranes
(C) Covalent bonding in nucleotides
(D) Ionic interactions in proteins
b
Which of the following explains why nucleotides are added in a 5’ to 3’ direction during DNA replication?
(A) The phosphate group on the 5’ carbon forms phosphodiester bonds with the 3’ hydroxyl group of the next nucleotide.
(B) DNA polymerase can only add nucleotides at the 5’ end of a growing strand.
(C) The nitrogenous base must be attached before the sugar-phosphate backbone is formed.
(D) The antiparallel structure of DNA prevents 3’ to 5’ replication.
a
Which characteristic of RNA allows it to perform multiple cellular functions?
(A) Its double-stranded structure makes it stable in all conditions.
(B) Its ability to form secondary structures enables enzymatic activity.
(C) Its covalent bonds prevent degradation.
(D) RNA is only involved in transcription, not translation.
b
Which of the following best explains why DNA structure is stable yet flexible enough for replication?
(A) The sugar-phosphate backbone provides strength, while weak hydrogen bonds allow strand separation.
(B) The nitrogenous bases form strong covalent bonds that prevent mutations.
(C) DNA lacks polarity, making it resistant to breaking.
(D) The double-helix is held together only by van der Waals forces.
a
